Digital 8508 Service manual

Digital 8508 Service manual
®
8508A
Reference Multimeter
Service Manual
September 2004
Rev. 1, 8/08
© 2004, 2008 Fluke Corporation, All rights reserved. Specifications are subject to change without notice
All product names are trademarks of their respective companies.
Manual Supplement
Manual Title: 8508A Service
Print Date:
July 2002
Revision/Date: 1, 8/08
Supplement Issue:
Issue Date:
Page Count:
1
3/09
1
This supplement contains information necessary to ensure the accuracy of the
above manual. This manual is distributed as an electronic manual on the
following CD-ROM:
CD Title:
CD Rev. & Date:
CD PN:
© 2009 Fluke Corporation. All rights reserved. Printed in U.K.
8508A
2, 8/2008
2150143
x
8508A Service
Manual Supplement
Change #1
On page 4-12, replace Table 4-1 with the following:
Table 4-1. Power Input Fuse 1
8508A Line
Setting
Manufacturer Part
Number
Size
230 V Line
630 mA 250 V
20 mm
(TH)
Schurter 001.2502
1582145
115 V line
1.25 A 250 V
20 mm
(TH)
Schurter 001.2505
1582150
100 V Line
1.6 A 250 V
20 mm
(F)
Schurter 0001.1006
1582072
3/09
Type
Fluke Part
Number
Rating
1
Warranty
Each Fluke product is warranted to be free from defects in material and workmanship under normal use and
service. The warranty period is one year and begins on the date of shipment. Parts, product repairs, and
services are warranted for 90 days. This warranty extends only to the original buyer or end-user customer of
a Fluke authorized reseller, and does not apply to fuses, disposable batteries, or to any product which, in
Fluke's opinion, has been misused, altered, neglected, contaminated, or damaged by accident or abnormal
conditions of operation or handling. Fluke warrants that software will operate substantially in accordance
with its functional specifications for 90 days and that it has been properly recorded on non-defective media.
Fluke does not warrant that software will be error free or operate without interruption.
Fluke authorized resellers shall extend this warranty on new and unused products to end-user customers
only but have no authority to extend a greater or different warranty on behalf of Fluke. Warranty support is
available only if product is purchased through a Fluke authorized sales outlet or Buyer has paid the
applicable international price. Fluke reserves the right to invoice Buyer for importation costs of
repair/replacement parts when product purchased in one country is submitted for repair in another country.
Fluke's warranty obligation is limited, at Fluke's option, to refund of the purchase price, free of charge repair,
or replacement of a defective product which is returned to a Fluke authorized service center within the
warranty period.
To obtain warranty service, contact your nearest Fluke authorized service center to obtain return
authorization information, then send the product to that service center, with a description of the difficulty,
postage and insurance prepaid (FOB Destination). Fluke assumes no risk for damage in transit. Following
warranty repair, the product will be returned to Buyer, transportation prepaid (FOB Destination). If Fluke
determines that failure was caused by neglect, misuse, contamination, alteration, accident, or abnormal
condition of operation or handling, including overvoltage failures caused by use outside the product’s
specified rating, or normal wear and tear of mechanical components, Fluke will provide an estimate of repair
costs and obtain authorization before commencing the work. Following repair, the product will be returned to
the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges
(FOB Shipping Point).
THIS WARRANTY IS BUYER'S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE SHALL NOT BE LIABLE
FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OR LOSSES,
INCLUDING LOSS OF DATA, ARISING FROM ANY CAUSE OR THEORY.
Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or
limitation of incidental or consequential damages, the limitations and exclusions of this warranty may not
apply to every buyer. If any provision of this Warranty is held invalid or unenforceable by a court or other
decision-maker of competent jurisdiction, such holding will not affect the validity or enforceability of any other
provision.
Fluke Corporation
P.O. Box 9090
Everett, WA 98206-9090
U.S.A.
11/99
To register your product online, visit register.fluke.com
Fluke Europe B.V.
P.O. Box 1186
5602 BD Eindhoven
The Netherlands
Table of Contents
Chapter
1
Title
Introduction and Specifications......................................................... 1-1
Introduction........................................................................................................
Safety Considerations ........................................................................................
Symbols .........................................................................................................
Service Information ...........................................................................................
How to Contact fluke .........................................................................................
Specifications.....................................................................................................
General Specifications...................................................................................
Maximum Voltage and Current Inputs..........................................................
DC and AC Voltage ..................................................................................
DC and AC Current...................................................................................
Resistance and Temperature .....................................................................
DC Voltage....................................................................................................
DC Current ....................................................................................................
AC Voltage....................................................................................................
AC Current ....................................................................................................
Resistance ......................................................................................................
Temperature...................................................................................................
Read Rate and Additional Uncertainty ..........................................................
Applying the Specifications...............................................................................
Introduction ...................................................................................................
Absolute and Relative Specifications ............................................................
Applying User’s Calibration Uncertainties ...................................................
Operating and Calibration Temperature Ranges ...........................................
Applying Temperature Coefficient Specifications ........................................
Ratio Measurements ......................................................................................
Additional Errors ...........................................................................................
2
Page
1-3
1-3
1-5
1-6
1-6
1-6
1-7
1-8
1-8
1-8
1-8
1-9
1-10
1-11
1-13
1-15
1-17
1-18
1-19
1-19
1-19
1-20
1-20
1-20
1-21
1-21
Theory of Operation ............................................................................ 2-1
Introduction........................................................................................................
Overall Functional Description..........................................................................
Main Assemblies ...........................................................................................
Power Supplies ..............................................................................................
i
2-3
2-3
2-3
2-6
8508A
Service Manual
3
Calibration and Verification................................................................ 3-1
Introduction........................................................................................................
Calibration Overview.........................................................................................
Calibration Interval and Performance ................................................................
Calibration Points ..............................................................................................
Non-Nominal Values.....................................................................................
Enabling Access to Calibration Mode ...............................................................
Calibration Menus..............................................................................................
Accessing the Calibration Menus and Calibration Mode ..............................
Calibration Menu...........................................................................................
SET VALUE Menu .......................................................................................
SPOT CAL Menu ..........................................................................................
SPOT (1 to 6) RMS Menus ...........................................................................
SPOT FREQUENCY (1 to 6) Menu .............................................................
Special Calibration ........................................................................................
SPCL Menu ...................................................................................................
SER # = Menu ...............................................................................................
Hvlin Menu....................................................................................................
Non-volatile input offset compensation.............................................................
Routine Calibration............................................................................................
Equipment Required for Calibration .............................................................
Preparing for Calibration ...............................................................................
Interconnections ............................................................................................
ADC Calibration............................................................................................
DC Voltage Calibration .................................................................................
AC Voltage Calibration .................................................................................
Resistance Calibration ...................................................................................
DC Current Calibration .................................................................................
AC Current Calibration .................................................................................
Frequency Calibration ...................................................................................
Exit From Calibration Mode and Non-Volatile Input Offset Adjustment.....
Cal Due Date Entry and Calibration Mode Disable ......................................
ACV Spot Frequency Calibration......................................................................
Performance Verification...................................................................................
Equipment Requirements ..............................................................................
Interconnections ............................................................................................
Applicable Verification Tolerance and Conditions .......................................
Preparation.....................................................................................................
DC Voltage Checks .......................................................................................
AC Voltage Checks .......................................................................................
Resistance Checks .........................................................................................
DC Current Checks........................................................................................
AC Current Checks........................................................................................
Frequency Checks .........................................................................................
4
3-3
3-3
3-3
3-3
3-4
3-4
3-4
3-4
3-4
3-5
3-6
3-6
3-6
3-7
3-7
3-7
3-8
3-8
3-9
3-10
3-10
3-11
3-14
3-14
3-16
3-18
3-25
3-27
3-28
3-29
3-30
3-30
3-31
3-32
3-32
3-32
3-33
3-33
3-35
3-37
3-40
3-41
3-43
Maintenance......................................................................................... 4-1
Introduction........................................................................................................
Access Procedures .............................................................................................
Before You Start............................................................................................
Cabling and Wiring Connections ..................................................................
Removing the A1 DC PCA ...........................................................................
Removing the A2 AC PCA ...........................................................................
Removing the A3 Ohms PCA .......................................................................
Removing the A4 Digital PCA......................................................................
ii
4-3
4-3
4-3
4-4
4-5
4-6
4-7
4-8
Contents (continued)
Removing the A5 Bezel Assembly................................................................
Removing the A5A1 Display PCA................................................................
Removing the A6 Rear Input Assembly........................................................
Fuse Replacement and Line-Voltage Selection .................................................
Line-Power Fuse F1 and Voltage Selection ..................................................
Rear-Input Current Fuse F2 (Rear Inputs Option).........................................
Self Test .............................................................................................................
Self-Test Errors .............................................................................................
Fatal Errors ....................................................................................................
Execution Errors............................................................................................
Device Dependant Errors ..............................................................................
5
4-9
4-10
4-11
4-12
4-12
4-13
4-13
4-13
4-16
4-18
4-19
List of Replaceable Parts.................................................................... 5-1
Introduction........................................................................................................
How to Obtain Parts...........................................................................................
How to Contact Fluke ........................................................................................
Parts Lists...........................................................................................................
iii
5-3
5-3
5-3
5-4
8508A
Service Manual
iv
List of Tables
Table
3-1.
3-2.
3-3.
3-4.
3-5.
3-6.
3-7.
3-8.
3-9.
3-10.
3-11.
3-12.
4-1.
4-2.
4-3.
4-4.
4-5.
4-6.
4-7.
4-8.
4-9.
5-1.
5-2.
5-2.
5-4.
Title
Required Equipment for Calibration and Performance Verification......................
Calibration Sequence .............................................................................................
DC Voltage Calibration Points and Sequence........................................................
AC Voltage Calibration Points and Sequence........................................................
Resistance Calibration Points and Sequence..........................................................
DC Current Calibration Points and Sequence ........................................................
AC Current Calibration Points and Sequence ........................................................
DC Voltage Verification Points and Sequence ......................................................
AC Voltage Verification Points and Sequence ......................................................
Resistance Verification Points and Sequence ........................................................
DC Current Verification Points and Sequence.......................................................
AC Current Verification Points and Sequence.......................................................
Power Input Fuse 1.................................................................................................
Current Function Rear Input Fuse 2 .......................................................................
Self-Test Errors ......................................................................................................
9000 System Kernel Fault Errors ...........................................................................
Unexpected Exception Errors.................................................................................
Serial Interface Errors ............................................................................................
Serial Loop Mismatch Errors .................................................................................
Execution Errors.....................................................................................................
Device Dependent Errors .......................................................................................
8508A Final Assembly...........................................................................................
8508A Chassis Assembly.......................................................................................
Bezel (front panel) Assembly.................................................................................
A6Rear Input Assembly (optional) ........................................................................
v
Page
3-10
3-11
3-15
3-17
3-18
3-26
3-28
3-34
3-36
3-39
3-41
3-42
4-12
4-13
4-13
4-16
4-16
4-17
4-18
4-19
4-20
5-4
5-6
5-7
5-12
8508A
Service Manual
vi
List of Figures
Figure
1-1.
2-1.
2-2.
3-1.
4-1.
4-3.
4-4.
4-5.
4-6.
4-7.
4-8.
4-9.
5-1.
5-2.
5-3.
5-4.
Title
8508A Dimentional Outline Drawing ....................................................................
8508A Functional Block Diagram .........................................................................
Power Supplies - Simplified Block Diagram .........................................................
Equipment Connections Required for Calibration .................................................
Internal Wiring and Cabling Diagram....................................................................
Removing the A2 AC PCA ....................................................................................
Removing the A3 Ohms PCA ................................................................................
Removing the A4 Digital PCA...............................................................................
Removing the A5 Bezel Assembly ........................................................................
Removing the A5A1 Display PCA ........................................................................
Removing the A6 Rear Input Assembly ................................................................
Rear Panel - Power Input Fuse and line Power Locations .....................................
8508A Final Assembly...........................................................................................
8508A Chassis Assembly.......................................................................................
A5 Bezel (front panel) Assembly...........................................................................
Rear Input Assembly (optional) .............................................................................
vii
Page
1-6
2-4
2-7
3-13
4-4
4-6
4-7
4-8
4-9
4-10
4-11
4-12
5-5
5-7
5-11
5-14
8508A
Service Manual
viii
riešenia na presné meranie
Chapter 1
Introduction and Specifications
Title
Introduction..........................................................................................................
Safety Considerations ..........................................................................................
Symbols ...........................................................................................................
Service Information .............................................................................................
How to Contact fluke ...........................................................................................
Specifications.......................................................................................................
General Specifications.....................................................................................
Maximum Voltage and Current Inputs............................................................
DC and AC Voltage ....................................................................................
DC and AC Current.....................................................................................
Resistance and Temperature .......................................................................
DC Voltage......................................................................................................
DC Current ......................................................................................................
AC Voltage......................................................................................................
AC Current ......................................................................................................
Resistance ........................................................................................................
Temperature.....................................................................................................
Read Rate and Additional Uncertainty ............................................................
Applying the Specifications.................................................................................
Introduction .....................................................................................................
Absolute and Relative Specifications ..............................................................
Applying User’s Calibration Uncertainties .....................................................
Operating and Calibration Temperature Ranges .............................................
Applying Temperature Coefficient Specifications ..........................................
Ratio Measurements ........................................................................................
Additional Errors .............................................................................................
http://www.elso.sk
Page
1-3
1-3
1-5
1-6
1-6
1-6
1-7
1-8
1-8
1-8
1-8
1-9
1-10
1-11
1-13
1-15
1-17
1-18
1-19
1-19
1-19
1-20
1-20
1-20
1-21
1-21
1-1
8508A
Service Manual
1-2
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Introduction
1
Introduction
The Fluke 8508A Reference Multimeter (hereafter "the Multimeter") is designed for the
most demanding measurement applications and provides extremely high measurement
precision in both stand-alone and systems applications.
This Service Manual provides the information necessary to maintain the Multimeter at a
module (or board) level. A brief description of the information contained in the various
chapters follows:
Chapter 1 Introduction and Specification provides a brief description of the product,
safety information regarding the product and its use, and a complete set of detailed
specifications.
Chapter 2 Theory of Operation provides an overall functional description of the internal
workings of the Multimeter. The intent of the theory is to aid in locating and isolating a
faulty PCA.
Chapter 3 Calibration and Verification provides a thorough and complete description of
both the Verification and the Calibration procedures for the Multimeter.
Chapter 4 Maintenance provides detailed descriptions of how to disassemble the
Multimeter to the PCA level. The purpose of the descriptions is to assist with equipment
repairs at the PCA level.
Chapter 5 List of Replaceable Parts provides all of the information required to identify
and order replacement parts for repairing the Multimenter at the PCA level.
XW Warning
To avoid electric shock, personal injury, or death, carefully read
the information under Safety Considerations before attempting
to install, use, or service the Multimeter.
Safety Considerations
This instrument has been designed and tested in accordance with the European standard
publication EN61010-1: 2001 and U.S. / Canadian standard publications UL 61010-1A1
and CAN/CSA-C22.2 No.61010.1. The instrument has been supplied in a safe condition.
This manual contains information and warnings that must be observed to keep the
instrument in a safe condition and ensure safe operation.
Using or servicing this Multimeter in conditions other than as specified in the Service
Manual could compromise your safety.
To use the Multimeter correctly and safely, read and adhere to the precautions on the
Safety Page and follow all the safety instructions or warnings given throughout this
manual and the Users Manual that relate to specific measurement functions. In addition,
follow all generally accepted safety practices and procedures required when working with
and around electricity.
http://www.elso.sk
1-3
8508A
Service Manual
riešenia na presné meranie
XW Safety – Read First
Warning: To avoid possible electric shock, personal injury, or death, read the following
before using the Multimeter:
1-4
⇒
Use the Multimeter only as specified in this manual, or the protection provided by
the Multimeter might be impaired.
⇒
Do not use the Multimeter in wet environments.
⇒
The Multimer can output lethal voltages. Use it only as described in this manual.
⇒
Inspect the Multimeter before using it. Do not use the Multimeter if it appears
damaged. Pay particular attention to the insulation around the connectors.
⇒
Inspect the test leads before use. Do not use them if insulation is damaged or metal
is exposed. Check the test leads for continuity. Replace damaged test leads before
using the Multimeter.
⇒
Verify the Multimeter's operation by measuring a known voltage before and after
using it. Do not use the Multimeter if it operates abnormally. Protection may be
impaired. If in doubt, have the Multimeter serviced.
⇒
Whenever it is likely that safety protection has been impaired, make the Multimeter
inoperative and secure it against any unintended operation.
⇒
Have the Multimeter serviced only by qualified service personnel.
⇒
Do not apply more than the rated voltage, as marked on the Multimeter, between
the terminals or between any terminal and earth ground.
⇒
Always use the power cord and connector appropriate for the voltage and outlet of
the country or location in which you are working.
⇒
Remove test leads from the Multimeter before opening the case.
⇒
Never remove the cover or open the case of an instrument without first removing
the power source.
⇒
Never operate the Multimeter with the cover removed or the case open.
⇒
Use caution when working with voltages above 30 V ac rms, 42 V ac peak, or 42 V
dc. These voltages pose a shock hazard.
⇒
Use only the replacement fuse(s) specified by the manual.
⇒
Use the proper terminals, function, and range for your measurements.
⇒
Do not operate the Multimeter around explosive gas, vapor, or dust.
⇒
When using probes, keep your fingers behind the finger guards.
⇒
When making electrical connections, connect the common test lead before
connecting the live test lead; when disconnecting, disconnect the live test lead
before disconnecting the common test lead.
⇒
Disconnect circuit power and discharge all high-voltage capacitors before testing
resistance, continuity, diodes, or capacitance.
⇒
Before measuring current, check the Multimeter's fuses and turn OFF power to the
circuit before connecting the Multimeter to the circuit.
⇒
When servicing the Multimeter, use only specified replacement parts.
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Safety Considerations
1
Symbols
The following safety and electrical symbols may be used on the Multimeter or in this
manual.
W
Risk of danger.
+
Power ON / OFF
J
Earth ground.
Important information. See manual.
X
Hazardous voltage. Voltage > 30 V dc or
ac peak might be present
B
AC (Alternating Current).
CAT
IEC 61010 Overvoltage (installation or
measurement) Category .
F
DC (Direct Current).
I
Fuse.
AC or DC (Alternating or Direct Current)
~
Do not dispose of this product as unsorted
municipal waste. Go to Fluke’s website for
recycling information.
H
Digital signal.
<
Recycle.
Y
Potentially hazardous voltage.
T
Double insulated.
D
or
C
http://www.elso.sk
1-5
riešenia na presné meranie
8508A
Service Manual
Service Information
In case of difficulty within the 1-year Warranty period, return the Multimeter to a Fluke
Service Center for Warranty repair. For out of Warranty repair, contact a Fluke Service
Center for a cost estimate.
This service manual provides instructions for verification of performance, calibration,
and maintenance. If you choose to repair a malfunction, information in this manual can
help you to determine which module (PCA) has a fault. See Chapter 5 for cautions about
handling the internal components.
How to Contact fluke
To contact Fluke, call one of the following telephone numbers:
USA: 1-888-99-FLUKE (1-888-993-5853)
Canada: 1-800-36-FLUKE (1-800-363-5853)
Europe: +31 402-675-200
Japan: +81-3-3434-0181
Singapore: +65-738-5655
Anywhere in the world: +1-425-446-5500
Or, visit Fluke's Web site at www.fluke.com.
To register your product, visit register.fluke.com
Specifications
Figure 1-1 shows the overall dimensions of the 8505A Reference Multimeter.
427 mm
(16.8 in)
8.8 mm
(3.5 in)
487 mm
(19.2 in)
avw001f.eps
Figure 1-1. 8508A Dimentional Outline Drawing
1-6
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Specifications
1
General Specifications
Power
Voltage
115 V Setting ..................................................... 100 V to 120 V rms ±10 %
230 V Setting ..................................................... 200 V to 240 V rms ±10 %
Frequency ............................................................... 47 Hz to 63 Hz
Consumption........................................................... < 80 VA
Dimensions
Height...................................................................... 88 mm (3.5 inches)
Width....................................................................... 427 mm (16.8 inches)
Depth ...................................................................... 487 mm (19.2 inches)
Weight..................................................................... 11.5 kg (25.5 lbs)
Environment
Temperature
Operating ............................................................ 0 °C to 50 °C
Specified Operation ............................................ 5 °C to 40 °C
Calibration (TCal)................................................ 20 °C to 25 °C
Factory Cal Temp ............................................... 23 °C
Storage ............................................................... -20 °C to 70 °C
Warm Up............................................................. 4 hours to full uncertainty specification.
Relative Humidity (non- condensing)
Operating ........................................................... 5 °C to 40 °C < 90 %
Storage .............................................................. 0 °C to 70 °C < 95 %
Altitude
Operating ............................................................ < 2000 meters
Storage ............................................................... < 12000 meters
Vibration and Shock................................................ Complies with MIL-PRF-28800F Class 3.
Safety ..................................................................... Designed and tested to EN61010-1: 2001, UL 61010-1A1,
CAN/CSA-C22.2 No.61010.1, CE and ETL marked.
Pollution Degree 2.
Installation Category II.
Equipment Class I (single insulation / Earthed metal case).
Protection against water ingress IP4X (general indoor conditions).
Input circuitry and connections (creepage and clearances) designed to
interface at Installation or Measurement Category I.
EMC ........................................................................ EN50081-1 Class B, EN55011/22, EN61326-1:1998,
EN50082-1, EN55011 1991 Class B,
EN61000-6-1:2001, FCC Rules part 15 sub part J class B,
CETL and CE marked.
Measurement Isolation
Guard to Safety Ground ......................................... < 3300 pF, > 10 GΩ.
Lo to Guard
In Remote Guard ................................................ < 2800 pF, > 10 GΩ (Not in Resistance function).
In Local Guard .................................................... Lo and Guard terminals are internally shorted
(in Resistance < 2800 pF, > 10 GΩ).
Autorange
Range Up................................................................ 100 % of range.
Range Down ........................................................... 9 % of range (18 % on 1000 V range).
Remote Interface................................................... IEEE 488.2
Warranty ................................................................ 1 Year
http://www.elso.sk
1-7
riešenia na presné meranie
8508A
Service Manual
Maximum Voltage and Current Inputs
Notes to maximum voltage and current input specifications
•
Maximum DC input equal to maximum rms input. Maximum peak input is rms x 1.414
•
Specifications apply equally to front and rear input terminals except where noted below.
•
Front to rear isolation allows opposing polarity of maximum terminal voltage on each input.
•
Digital I/O Ground (DigGnd) is internally connected to Safety Ground (Ground).
DC and AC Voltage
Maximum rms terminal voltages
Ground
DigGnd
0V
Guard
650 V
650 V
A
1000 V
650 V
650 V
Sense Lo
250 V
1000 V
250 V
650 V
650 V
Lo
1000 V
250 V
650 V
650 V
Hi
1000 V
1000 V
1000 V
1000 V
1000 V
1000 V
Sense Hi
250 V
1000 V
1000 V
1000 V
1000 V
1000 V
1000 V
Notes
•
The A terminal is open circuit in these functions.
•
In 4wV mode Sense Hi is internally connected to Hi and Sense Lo is internally connected to Lo.
DC and AC Current
Maximum rms terminal voltages
Ground
DigGnd
0V
Guard
650 V
650 V
Front Input
Rear input
Guard
n.a
n.a
A
250 V
650 V
650 V
Sense Lo
250 V
250 V
250 V
650 V
650 V
Lo
5V
250 V
650 V
650 V
Hi
1000 V
1000 V
1000 V
1000 V
1000 V
1000 V
Sense Hi
250 V
1000 V
1000 V
1000 V
1000 V
1000 V
1000 V
Hi
n.a
n.a
Sense Hi
n.a
n.a
Maximum rms terminal currents
A
20 A
2A
Lo
20 A
2A
Sense Lo
n.a
n.a
Notes
•
The Sense Lo, Sense Hi, and Hi Terminals are open circuit in these functions.
•
The front input A terminal protection is automatic and self-resetting, and does not interrupt current flow. Damage is likely to
occur if more than 20 A is applied.
•
The rear input A terminal is protected by a fuse mounted on the rear panel.
Resistance and Temperature
Maximum rms terminal voltages
Ground
DigGnd
0V
Guard
650 V
650 V
A
250 V
650 V
650 V
Lo
250 V
250 V
650 V
650 V
Note
•
1-8
The A terminal is open circuit in these functions.
http://www.elso.sk
Sense Lo
250 V
250 V
250 V
650 V
650 V
Hi
250 V
250 V
250 V
250 V
1000 V
1000 V
Sense Hi
250 V
250 V
250 V
250 V
250 V
1000 V
1000 V
riešenia na presné meranie
Introduction and Specifications
Specifications
1
DC Voltage
DC Voltage [1] [2] [3]
Uncertainty Relative to Cal Stds
Absolute Uncertainties
[4]
Range
Full Scale
± (ppm Reading + ppm Range)
[15]
24 hour
TCal ±1 °C
95 % Confidence Level
200 mV
199.990 000
2V
1.999 900 00
20 V
19.999 000 0
200 V
199.990 000
1000 V
1050.000 00
99 % Confidence Level
200 mV
199.990 000
2V
1.999 900 00
20 V
19.999 000 0
200 V
199.990 000
1000 V
1050.000 00
Range
90 day
TCal ±1 °C
0.7 + 0.5
0.5 + 0.2
0.5 + 0.2
1.0 + 0.2
1.0 + 0.5
1.4 + 0.5
1.4 + 0.2
1.4 + 0.2
2.6 + 0.2
2.6 + 0.5
365 day
TCal ±1 °C
2.7 + 0.5
2.7 + 0.2
2.7 + 0.2
4.0 + 0.2
4.0 + 0.5
0.8 + 0.6
2.0 + 0.6
3.5 + 0.6
0.6 + 0.25
1.8 + 0.25
3.5 + 0.25
0.6 + 0.25
1.8 + 0.25
3.5 + 0.25
1.2 + 0.25
3.5 + 0.25
5.2 + 0.25
1.2 + 0.6
3.5 + 0.6
5.2 + 0.6
[1] [2] [3]
DC Voltage (Secondary Specifications)
365 day
TCal ±1 °C
365 day TCal
±5 °C
4.5 + 0.5
3.0 + 0.2
3.0 + 0.2
4.5 + 0.2
4.5 + 0.5
5.0 + 0.5
3.5 + 0.2
3.5 + 0.2
5.5 + 0.2
5.5 + 0.5
6.0 + 0.6
4.0 + 0.25
4.0 + 0.25
6.0 + 0.25
6.0 + 0.6
6.5 + 0.6
4.5 + 0.25
4.5 + 0.25
7.0 + 0.25
7.0 + 0.6
Temperature Coefficient
Transfer Uncertainty
20 mins ±1 °C ± (ppm
Reading+ ppm Range)
15 °C - 30 °C
0.4 + 0.3
0.12 + 0.1
0.12 + 0.1
0.4 + 0.1
0.4 + 0.3
0.4
0.3
0.3
0.7
0.7
5 °C - 15 °C
30 °C - 40 °C
± ppm Reading/°C
200 mV
2V
20 V
200 V
1000 V
0.6
0.5
0.5
1.0
1.0
Type ....................................................................... Multi-slope, multi-cycle A-D Converter
CMRR (1 kΩ unbalance)
NMRR
[5]
.................................... 140 dB at DC and 1 - 60 Hz
[5]
Filter Out ................................................................. 60 dB at 50/60 Hz ±0.09 %
Filter In .................................................................... 110 dB at 50/60 Hz ±0.09 %
Protection (All ranges)........................................... 1 kV rms
Input Impedance
200 mV to 20 V Ranges.......................................... > 10 GΩ
200 V & 1000 V Ranges ......................................... 10.1 MΩ ± 1 %
Max Input Current ................................................. 50 pA
Ratio Accuracy
Range to Range...................................................... ±(Net Front Input Accuracy + Net Rear Input Accuracy)
Within Range .......................................................... Apply 24 hour or 20 minute Transfer Uncertainty specifications
Settling Time (to 10 ppm step size)
Filter Out ................................................................. < 50 ms
Filter In .................................................................... < 1 s
http://www.elso.sk
1-9
riešenia na presné meranie
8508A
Service Manual
DC Current
DC Current
[1] [2] [3]
Uncertainty Relative to Cal Stds
Range
[15]
Full Scale
24 hour
TCal ±1 °C
95 % Confidence Level
200 μA
199.990 00
2 mA
1.999 900 0
20 mA
19.999 000
200 mA
199.990 00
2A
1.999 900 0
20 A
19.999 000
99 % Confidence Level
200 μA
199.990 00
2 mA
1.999 900 0
20 mA
19.999 000
200 mA
199.990 00
2A
1.999 900 0
20 A
19.999 000
Absolute Uncertainties
± (ppm Reading + ppm Range)
90 day
TCal ±1 °C
365 day
TCal ±1 °C
[4]
365 day
TCal ±1 °C
365 day
TCal ±5 °C
5.5 + 2.0
5.5 + 2.0
6.5 + 2.0
28 + 4.0
80 + 8.0
200 + 20
6.0 + 2.0
6.0 + 2.0
7.0 + 2.0
30 + 4.0
125 + 8.0
290 + 20
6.5 + 2.0
6.5 + 2.0
8.0 + 2.0
33 + 4.0
170 + 8.0
380 + 20
12 + 2.0
12 + 2.0
13 + 2.0
36 + 4.0
170 + 8.0
380 + 20
12 + 2.0
12 + 2.0
14 + 2.0
48 + 4.0
185 + 8.0
400 + 20
7.0 + 2.0
7.0 + 2.0
8.0 + 2.0
35 + 4.0
100 + 8.0
250 + 20
7.5 + 2.0
7.5 + 2.0
9.0 + 2.0
37 + 4.0
150 + 8.0
350 + 20
8.0 + 2.0
8.0 + 2.0
10 + 2.0
40 + 4.0
205 + 8.0
450 + 20
15 + 2.0
15 + 2.0
16 + 2.0
45 + 4.0
210 + 8.0
455 + 20
16 + 2.0
16 + 2.0
18 + 2.0
60 + 4.0
225 + 8.0
500 + 20
DC Current (Secondary Specifications) [1] [2] [3]
Temperature Coefficient
Range
200 μA
2 mA
20 mA
200 mA
2A
20 A
Input Impedance (Ω)
Front
Rear
150
15.2
1.8
1.2
0.3
0.04
150
15.2
1.9
1.3
0.4
-
15 °C - 30 °C
± ppm Reading/°C
0.4
0.4
1.2
6. 0
8.0
15
Type........................................................................ Multi-slope, multi-cycle A-D Converter
Protection
Front Input............................................................... 20 A rms
Rear Input ............................................................... 2 A rms, Rear Panel Fuse
Settling Time
200 μA to 200 mA Ranges, to 10 ppm step size .... Filter Out < 50 ms, Filter In < 1 s
2 A Range
to 100 ppm step size........................................... < 1 s
to 75 ppm step size............................................. < 30 s
to 30 ppm step size............................................. < 5 minutes
20 A Range (at 10 A)
to 300 ppm step size........................................... < 1 s
to 250 ppm step size........................................... < 30 s
to 100 ppm step size........................................... < 5 minutes
1-10
http://www.elso.sk
5 °C - 15 °C
30 °C - 40 °C
0.6
0.6
1.8
9.0
12
20
riešenia na presné meranie
Introduction and Specifications
Specifications
1
AC Voltage
AC Voltage
[1] [2] [6] [7]
Uncertainty Relative to Cal Stds
[9]
Absolute Uncertainties
[4]
Range
Full Scale
[15]
95% Confidence Level
200 mV
199.990 0
2 V, 20 V &
200 V
1.999 900
19.999 00
199.990 0
24 hour
TCal ±1 °C
90 day
TCal ±1 °C
365 day
TCal ±1 °C
365 day
TCal ±1 °C
365 day
TCal ±5 °C
1 - 10
10 - 40
40 - 100
100 - 2 k
2k - 10 k
10k - 30 k
30k - 100 k
80 + 70
80 + 20
60 + 20
40 + 10
60 + 20
250 + 30
400 + 100
120 + 70
120 + 20
100 + 20
100 + 10
100 + 20
300 + 40
700 + 100
120 + 70
120 + 20
100 + 20
100 + 10
100 + 20
300 + 40
700 + 100
160 + 70
130 + 20
110 + 20
105 + 10
105 + 20
305 + 40
705 + 100
165 + 70
140 + 20
115 + 20
110 + 10
135 + 20
340 + 40
765 + 100
1 - 10
10 - 40
40 - 100
100 - 2 k
70 + 60
70 + 10
50 + 10
30 + 10
100 + 60
100 + 10
80 + 10
60 + 10
100 + 60
100 + 10
80 + 10
60 + 10
140 + 60
105 + 10
85 + 10
65 + 10
150 + 60
115 + 10
90 + 10
75 + 10
2 k - 10 k
50 + 10
80 + 10
80 + 10
85 + 10
110 + 10
10 k - 30 k
100 + 20
200 + 20
200 + 20
205 + 20
220 + 20
250 + 100
500 +100
30 k - 100 k
100 k - 300 k
1000 V
[8]
1050.000
99% Confidence Level
200 mV
199.990 0
2 V, 20 V &
200 V
1000 V
[8]
± (ppm Reading + ppm Range)
Frequency (Hz)
0.15 % + 0.1 % 0.3 % + 0.1 %
500 +100
505 + 100
570 + 100
0.3 % + 0.1 %
0.3 % + 0.1 %
0.3 % + 0.1 %
300 k - 1 M
1 % + 0.5 %
1%+1%
1%+1%
1%+1%
1%+1%
1 - 10
10 - 40
40 - 10 k
10 k - 30 k
30 k - 100 k
70 + 70
70 + 20
50 + 20
100 + 40
250 + 200
100 + 70
100 + 20
80 + 20
200 + 40
500 + 200
100 + 70
100 + 20
80 + 20
200 + 40
500 + 200
140 + 70
110 + 20
95 + 20
205 + 40
510 + 200
150 + 70
120 + 20
115 + 20
225 + 40
580 + 200
1 - 10
10 - 40
40 - 100
100 - 2 k
2 k - 10 k
10 k - 30 k
30 k - 100 k
90 + 80
90 + 25
70 + 25
45 + 12
70 + 25
270 + 35
450 + 120
140 + 80
140 + 25
115 + 25
115 + 12
115 + 25
340 + 50
750 + 120
140 + 80
140 + 25
115 + 25
115 + 12
115 + 25
340 + 50
750 + 120
200 + 80
145 + 25
125 + 25
125 + 12
125 + 25
345 + 50
755 + 120
210 + 80
160 + 25
135 + 25
135 + 12
165 + 25
395 + 50
855 + 120
1.999 900
19.999 00
199.990 0
1 - 10
10 - 40
40 - 100
100 - 2 k
2 k - 10 k
10 k - 30 k
30 k - 100 k
100 k - 300 k
300 k - 1 M
1050.000
1 - 10
10 - 40
80 + 70
115 + 70
115 + 70
180 + 70
190 + 70
80 + 12
115 + 12
115 + 12
120 + 12
135 + 12
60 + 12
90 + 12
90 + 12
95 + 12
110 + 12
35 + 12
70 + 12
70 + 12
75 + 12
90 + 12
60 + 12
90 + 12
90 + 12
95 + 12
135 + 12
115 + 25
240 + 25
240 + 25
245 + 25
260 + 25
270 + 120
550 + 120
550 +120
555 + 120
650 + 120
0.15 %+0.12 % 0.3 %+0.12 % 0.3 % + 0.12 % 0.3 % + 0.12 % 0.3 % + 0.12 %
1 % + 0.6 %
1 % + 1.2 %
1 % + 1.2 %
1 % + 1.2 %
1 % + 1.2 %
80 + 80
80 + 25
115 + 80
115 + 25
115 + 80
115 + 25
180 + 80
135 + 25
190 + 80
145 + 25
140 + 25
40 - 10 k
60 + 25
90 + 25
90 + 25
110 + 25
10 k - 30 k
115 + 50
240 + 50
240 + 50
250 + 50
265 + 50
30 k - 100 k
270 + 250
600 + 250
600 + 250
615 + 250
700 + 250
http://www.elso.sk
1-11
riešenia na presné meranie
8508A
Service Manual
AC Voltage (Secondary Specifications)[1] [2]
Temperature Coefficient
5 °C - 15 °C
30 °C - 40 °C
Range
Frequency (Hz)
15 °C - 30 °C
200 mV
1 - 10
10 - 40
40 - 100
100 - 2 k
2 k - 10 k
10 k - 30 k
30 k - 100 k
5
5
5
5
12
15
40
10
10
10
10
20
20
60
2V
20 V
200 V
1 - 10
10 - 40
40 - 100
100 - 2 k
2 k - 10 k
10 k - 30 k
30 k - 100 k
100 k - 300 k
300 k - 1 M
5
5
5
5
10
12
40
60
80
10
10
10
10
15
20
60
90
120
1000 V
1 - 10
10 - 40
40 - 10 k
10 k - 30 k
30 k - 100 k
5
5
10
12
40
10
10
15
20
60
± ppm Reading/°C
Type ....................................................................... True rms, AC coupled measures AC component with up to 1000 V DC
(ac 2 + dc 2 )
bias on any range. DC coupled gives
CMRR (1 kΩ unbalance)
[5]
..................................... > 90 dB DC - 60 Hz
Crest Factor
200 mV to 200 V ranges ........................................ 10:1 at 12 % range, 5:1 at 50 % range, 2.5:1 at full range
1000 V range ......................................................... 10:1 at 25 % range, 5:1 at full range
Protection (All ranges)........................................... 1 kV rms
Input Impedance ................................................... 1 MΩ in parallel with 150 pF
DC Accuracy (DC Coupled)................................... Add ±(50 ppm Reading + 50 ppm Range + 20 μV)
Ratio Accuracy
Range to Range...................................................... ±(Net Front Input Accuracy + Net Rear Input Accuracy)
Within Range ......................................................... Apply 24 hour or 20 minute Transfer Uncertainty specifications
Settling Time (to 100 ppm step size)
100 Hz filter............................................................. < 0.5 s
40 Hz filter............................................................... < 1.25 s
10 Hz filter............................................................... < 5 s
1 Hz filter................................................................. < 50 s
Frequency Measurement
.
Signal Amplitude Range ......................................... 5 % of range to limit set by maximum V Hz
Gate Mode
1-12
Normal
Fast
Resolution......................................................... 6.5 digits
4.5 digits
Frequency Range ............................................. 10 Hz - 1 MHz
200 Hz - 1 MHz
Accuracy (1 year, 13 °C - 33 °C) ..................... ± (10 ppm of Reading + 2 digits)
± 2 digits
Sample Interval ................................................. 1 s
50 ms
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Specifications
1
AC Current
AC Current [1] [2] [6] [9]
Uncertainty Relative to Cal Stds
Range
Full Scale
[15]
95% Confidence Level
199.990 0
200 μA
2 mA &
20 mA
1.999 900
19.9990 00
200 mA
199.990 0
2A
1.999 900
20 A
19.999 00
99% Confidence Level
199.990 0
200 μA
2 mA &
20 mA
1.999 900
19.999 00
200 mA
199.990 0
2A
1.999 900
20 A
19.999 00
Frequency
(Hz)
[9]
Absolute Uncertainties
± (ppm Reading + ppm Range)
[4]
24 hour
TCal ±1 °C
90 day
TCal ±1 °C
365 day
TCal ±1 °C
365 day
TCal ±1 °C
365 day
TCal ±5 °C
1 - 10
10 - 10 k
10 k - 30 k
30 k - 100 k
1 - 10
10 - 10 k
10 k - 30 k
30 k - 100 k
1 - 10
10 -10 k
10 k - 30 k
10 - 2 k
2 k - 10 k
10 k - 30 k
10 - 2 k
2 k - 10 k
200 + 100
200 + 100
500 + 100
0.35 % + 100
200 + 100
200 + 100
500 + 100
0.35 % + 100
200 + 100
200 + 100
500 + 100
500 + 100
600 + 100
0.25 % + 100
700 + 100
0.2 % + 100
250 + 100
250 + 100
600 + 100
0.4 % + 100
250 + 100
250 + 100
600 + 100
0.4 % + 100
250 + 100
250 + 100
600 + 100
600 + 100
700 + 100
0.3 % + 100
800 + 100
0.25 % + 100
250 + 100
250 + 100
600 + 100
0.4 % + 100
250 + 100
250 + 100
600 + 100
0.4 % + 100
250 + 100
250 + 100
600 + 100
600 + 100
700 + 100
0.3 % + 100
800 + 100
0.25 % + 100
475 + 100
475 + 100
650 + 100
0.4 % + 100
290 + 100
280 + 100
650 + 100
0.4 % + 100
290 + 100
250 + 100
600 + 100
600 + 100
710 + 100
0.3 % + 100
800 + 100
0.25 % + 100
500 + 100
500 + 100
710 + 100
0.4 % + 100
310+ 100
300 + 100
710 + 100
0.4 % + 100
310 + 100
290 + 100
625 + 100
620 + 100
735 + 100
0.3 % + 100
820 + 100
0.25 % + 100
1 - 10
10 - 10 k
10 k - 30 k
30 k - 100 k
1 - 10
10 - 10 k
10 k - 30 k
30 k - 100 k
1 - 10
10 - 10 k
10 k - 30 k
10 - 2 k
2 k - 10 k
10 k - 30 k
10 - 2 k
2 k - 10 k
250 + 120
250 + 120
600 + 120
0.35 % + 120
250 + 120
250 + 120
600+ 120
0.35 % + 120
250 + 120
250 + 120
600 + 120
600 + 120
700 + 120
0.25 % + 120
800 + 120
0.2 % + 120
300 + 120
300 + 120
700 + 120
0.4 % + 120
300 + 120
300 + 120
700 + 120
0.4 % + 120
300 + 120
300 + 120
700 + 120
700 + 120
800 + 120
0.3 % + 120
900 + 120
0.25 % + 120
300 + 120
300 + 120
700 + 120
0.4 % + 120
300 + 120
300 + 120
700 + 120
0.4 % + 120
300 + 120
300 + 120
700 + 120
700 + 120
800 + 120
0.3 % + 120
900 + 120
0.25 % + 120
590 + 120
590 + 120
775 + 120
0.4 % + 120
380 + 120
340 + 120
775 + 120
0.4 % + 120
380 + 120
305 + 120
700 + 120
705 + 120
815 + 120
0.3 % + 120
900 + 120
0.25 % + 120
620 + 120
620 + 120
800 + 120
0.4 % + 120
400 + 120
370 + 120
800 + 120
0.4 % + 120
400 + 120
360 + 120
740 + 120
725 + 120
860 + 120
0.3 % + 120
920 + 120
0.25 % + 120
http://www.elso.sk
1-13
riešenia na presné meranie
8508A
Service Manual
AC Current (Secondary Specifications) [1] [2] [6] [9]
Temperature Coefficient
Range
Frequency (Hz)
± ppm Reading/°C
200 μA, 2 mA & 1 - 10
20 mA
10 - 10 k
10 k - 30 k
30 k - 100 k
200 mA
1 - 10
10 - 10 k
10 k - 30 k
2A
10 - 2 k
2 k - 10 k
10 k - 30 k
20 A
10 - 2 k
2 k - 10 k
10
10
12
40
10
15
15
10
15
20
20
25
Input Impedance (Ω)
5 °C - 15 °C
30 °C - 40 °C
15 °C - 30 °C
15
15
20
60
15
20
20
15
20
30
25
30
Range
200 μA
2 mA
20 mA
Front
Rear
150
15.2
1.8
150
15.2
1.9
1.2
1.3
0.3
0.4
0.04
-
Type........................................................................ True rms, AC coupled. DC coupled gives
(ac2 + dc 2 )
Crest Factor........................................................... 3:1 at 50 % range, 1.5:1 at full range
Protection
Front Input............................................................... 20 A rms
Rear Input ............................................................... 2 A rms, Rear Panel Fuse
Settling Time
200 μA to 200 mA Ranges 2 A Range
to 100 ppm of step
100 Hz filter............................................................. < 0.5 s
1-14
20 A Range (at 10 A)
to 100 ppm of step to 300 ppm of step
<1s
<1s
40 Hz filter............................................................... < 1.25 s
<2s
<2s
10 Hz filter............................................................... < 5 s
< 10 s
< 10 s
1 Hz filter................................................................. < 50 s
< 50 s
< 50 s
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Specifications
1
Resistance
Resistance [1] [2] [3] [9]
Uncertainty Relative to Cal Stds
Range
Full Scale
[15]
95% Confidence Level
2Ω
1.999 900 00
20 Ω
19.999 000 0
200 Ω
199.990 000
2 kΩ
1.999 900 00
20 kΩ
19.999 000 0
200 kΩ
199.990 000
2 MΩ
1.999 900 00
20 MΩ
19.999 000 0
200 MΩ
199.990 000
2 GΩ
1.999 900 00
2Ω
1.999 900 00
20 Ω
19.999 000 0
200 Ω
199.990 000
2 kΩ
1.999 900 00
20 kΩ
19.999 000 0
200 kΩ
199.990 000
2 MΩ
1.999 900 00
20 MΩ
19.999 000 0
200 MΩ
199.990 000
2 GΩ
1.999 900 00
20 MΩ
19.999 000 0
200 MΩ
199.990 000
2 GΩ
1.999 900 00
20 GΩ
19.999 000 0
99% Confidence Level
2Ω
1.999 900 00
20 Ω
19.999 000 0
200 Ω
199.990 000
2 kΩ
1.999 900 00
20 kΩ
19.999 000 0
200 kΩ
199.990 000
2 MΩ
1.999 900 00
20 MΩ
19.999 000 0
200 MΩ
199.990 000
2 GΩ
1.999 900 00
2Ω
1.999 900 00
20 Ω
19.999 000 0
200 Ω
199.990 000
2 kΩ
1.999 900 00
20 kΩ
19.999 000 0
200 kΩ
199.990 000
2 MΩ
1.999 900 00
20 MΩ
19.999 000 0
200 MΩ
199.990 000
2 GΩ
1.999 900 00
20 MΩ
19.999 000 0
200 MΩ
199.990 000
Mode
Absolute Uncertainties
± (ppm Reading + ppm Range)
[10]
[4]
24 hour
TCal ±1 °C
90 day
TCal ±1 °C
365 day
TCal ±1 °C
365 day
TCal ±1 °C
365 day
TCal ±5 °C
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
High Voltage
High Voltage
High Voltage
High Voltage
5.0 + 2.0
2.5 + 0.7
1.5 + 0.25
1.0 + 0.25
1.0 + 0.25
1.0 + 0.25
2.0 + 0.5
3.5 + 5.0
20 + 50
250 + 500
5.0 + 2.0
2.5 + 0.7
2.5 + 0.7
2.5 + 0.7
2.5 + 0.7
5.0 + 0.5
7.0 + 0.5
20 + 5.0
250 + 500
250 + 500
2.0 + 0.5
3.5 + 5.0
20 + 50
250 + 500
8.0 + 2.0
4.5 + 0.7
4.0 + 0.25
3.5 + 0.25
3.5 + 0.25
3.5 + 0.25
4.0 + 0.5
6.0 + 5.0
25 + 50
350 + 500
8.0 + 2.0
4.5 + 0.7
5.0 + 0.7
5.0 + 0.7
5.0 + 0.7
6.5 + 0.5
8.0 + 0.5
20 + 5.0
350 + 500
350 + 500
4.0 + 0.5
6.0 + 5.0
25 + 50
350 + 500
10 + 2.0
7.0 + 0.7
7.0 + 0.25
7.0 + 0.25
7.0 + 0.25
7.0 + 0.25
7.0 + 0.5
9.0 + 5.0
30 + 50
500 + 500
10 + 2.0
7.0 + 0.7
7.0 + 0.7
7.0 + 0.7
7.0 + 0.7
7.0 + 0.5
9.0 + 0.5
25 + 5.0
500 + 500
500 + 500
7.0 + 0.5
9.0 + 5.0
30 + 50
500 + 500
15 + 2.0
9.0 + 0.7
7.5 + 0.25
7.5 + 0.25
7.5 + 0.25
7.5 + 0.25
8.5 + 0.5
15 + 5.0
60 + 50
525 + 500
15 + 2.0
9.0 + 0.7
7.5 + 0.7
7.5 + 0.7
7.5 + 0.7
7.5 + 0.5
10 + 0.5
35 + 5.0
515 + 500
525 + 500
15 + 0.5
60 + 5.0
150 + 50
525 + 500
17 + 2.0
9.5 + 0.7
8.0 + 0.25
8.0 + 0.25
8.0 + 0.25
8.0 + 0.25
9.0 + 0.5
20 + 5.0
120 + 50
1510 + 500
17 + 2.0
9.5 + 0.7
8.0 + 0.7
8.0 + 0.7
8.0 + 0.7
8.0 + 0.5
15 + 0.5
90 + 5.0
1505 + 500
1510 + 500
17 + 0.5
65 + 5.0
180 + 50
1510 + 500
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Normal
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
Lo Current
High Voltage
High Voltage
6.0 + 2.5
3.0 + 0.9
1.8 + 0.3
1.2 + 0.3
1.2 + 0.3
1.2 + 0.3
2.5 + 0.6
4.5 + 6.0
25 + 60
325 + 600
6.0 + 2.5
3.0 + 0.9
3.0 + 0.9
3.0 + 0.9
3.0 + 0.9
6.0 + 0.6
8.0 + 0.6
25 + 6.0
325 + 600
325 + 600
2.5 + 0.6
4.5 + 6.0
10 + 2.5
5.5 + 0.9
5.0 + 0.3
4.5 + 0.3
4.5 + 0.3
4.5 + 0.3
5.0 + 0.6
7.5 + 6.0
30 + 60
450 + 600
10 + 2.5
5.5 + 0.9
6.5 + 0.9
6.5 + 0.9
6.5 + 0.9
8.0 + 0.6
10.0 + 0.6
25 + 6.0
450 + 600
450 + 600
5.0 + 0.6
7.5 + 6.0
12 + 2.5
8.5 + 0.9
8.5 + 0.3
8.5 + 0.3
8.5 + 0.3
8.5 + 0.3
8.5 + 0.6
12 + 6.0
35 + 60
650 + 600
12 + 2.5
8.5 + 0.9
8.5 + 0.9
8.5 + 0.9
8.5 + 0.9
9.0 + 0.6
12.0 + 0.6
30 + 6.0
650 + 600
650 + 600
8.5 + 0.6
12 + 6.0
19 + 2.5
11.5 + 0.9
9.5 + 0.3
9.5 + 0.3
9.5 + 0.3
9.5 + 0.3
10.5 + 0.6
20 + 6.0
75 + 60
675 + 600
19 + 2.5
11.5 + 0.9
9.5 + 0.9
9.5 + 0.9
9.5 + 0.9
9.5 + 0.6
13.0 + 0.6
45 + 6.0
670 + 600
675 + 600
19 + 0.6
75 + 6.0
22 + 2.5
12.0 + 0.9
10 + 0.3
10 + 0.3
10 + 0.3
10 + 0.3
12 + 0.6
25 + 6.0
150 + 60
1810 + 600
22 + 2.5
12.0 + 0.9
10.0 + 0.9
10.0 + 0.9
10.0 + 0.9
10.0 + 0.6
17.0 + 0.6
110 + 6.0
1810 + 600
1810 + 600
20 + 0.6
80 + 6.0
2 GΩ
1.999 900 00
High Voltage
25 + 60
30 + 60
35 + 60
195 + 60
230 + 60
20 GΩ
19.999 000 0
High Voltage
325 + 600
450 + 600
650 + 600
675 + 600
1810 + 600
http://www.elso.sk
1-15
riešenia na presné meranie
8508A
Service Manual
Resistance - Normal Mode (Secondary Specifications) [1] [2] [3] [10]
Range
Measurement Current
2Ω
20 Ω
200 Ω
2 kΩ
20 kΩ
200 kΩ
2 MΩ
20 MΩ
200 MΩ
2 GΩ
100 mA
10 mA
10 mA
1 mA
100 μA
100 μA
10 μA
1 μA
100 nA
10 nA
Temperature Coefficient
Transfer Uncertainty
20 mins ±1 °C
± (ppm Reading
+ ppm Range)
15 °C - 30 °C
2.0 + 2.0
0.8 + 0.7
0.2 + 0.15
0.2 + 0.15
0.2 + 0.15
0.2 + 0.15
0.5 + 0.5
2.5 + 5
15 + 50
200 + 500
1.5
0.6
0.5
0.5
0.5
0.5
0.6
2
20
200
± ppm Reading/°C
2.5
1.0
0.8
0.8
0.8
0.8
1.0
3
30
300
Resistance - Lo Current Mode (Secondary Specifications)
Range
Measurement Current
2Ω
20 Ω
200 Ω
2 kΩ
20 kΩ
200 kΩ
2 MΩ
20 MΩ
200 MΩ
2 GΩ
100 mA
10 mA
1 mA
100 μA
10 μA
10 μA
1 μA
100 nA
10 nA
10 nA
5 °C - 15 °C
30 °C - 40 °C
[1] [2] [3] [10]
Temperature Coefficient
Transfer Uncertainty
20 mins ±1 °C
± (ppm Reading
+ ppm Range)
15 °C - 30 °C
2.0 + 2.0
0.8 + 0.7
0.8 + 0.7
0.8 + 0.7
0.8 + 0.7
0.5 + 0.5
2.0 + 0.5
15 + 5
200 + 500
200 + 500
1.5
0.6
0.6
0.6
0.6
0.6
2
20
200
200
5 °C - 15 °C
30 °C - 40 °C
± ppm Reading/°C
2.5
1.0
1.0
1.0
1.0
1.0
3
30
300
300
Resistance - High Voltage Mode (Secondary Specifications) [1] [2] [3]
Range
[9]
20 MΩ
200 MΩ
2 GΩ
20 GΩ
Measurement Current
10 μA
1 μA
100 nA
10 nA
Temperature Coefficient
Transfer Uncertainty
20 mins ±1 °C
± (ppm Reading
+ ppm Range)
15 °C - 30 °C
0.5 + 0.5
2.0 + 0.5
15 + 50
200 + 500
0.6
2.0
20
200
5 °C - 15 °C
30 °C - 40 °C
± ppm Reading/°C
1.0
3
30
300
Type........................................................................ True 4-wire with Ohms guard. 2-wire selectable.
Max Lead Resistance............................................ 10 Ω in any or all leads, 1 Ω on 2 Ω range
Full Scale Measurement Voltage
Normal Mode .......................................................... 200 mV/2 V/20 V
Lo Current Mode ..................................................... 200 mV/2 V
High Voltage Mode ................................................. 200 V
Protection (All ranges) .......................................... 250 V rms, 360 V pk
Ratio Accuracy
Range to Range...................................................... ±(Net Front Input Accuracy + Net Rear Input Accuracy)
Within Range .......................................................... Apply 24 hour or 20 minute Transfer Uncertainty specifications
Settling Time ......................................................... Up to 200 kΩ range generally the same as DC Voltage Filter In but
depends on external connections
1-16
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Specifications
1
Temperature
Temperature Readout [1] [2] [3]
Typical Equivalent Temperature Measurement Uncertainty
Absolute Resistance
Measurement Uncertainty
[4]
365 day Tcal ±1 °C
[11]
±(ppm Reading + mΩ)
[12]
Probe Type
Nominal
Temperature
(°C)
Resistance
(Ω)
Accuracy
± (°C)
7.5 + 0.14
25 Ω PRT/SPRT
25 Ω PRT/SPRT
25 Ω PRT/SPRT
100 Ω PRT/SPRT
100 Ω PRT/SPRT
100 Ω PRT/SPRT
-200
0
660
-200
0
232
5
25
84
20
100
185
0.0085
0.0035
0.0025
0.0035
0.0025
0.0020
7.5 + 0.5
100 Ω PRT/SPRT
400
250
0.0025
0 - 199.990 000 Ω
9.5 + 0.18
25 Ω PRT/SPRT
25 Ω PRT/SPRT
25 Ω PRT/SPRT
100 Ω PRT/SPRT
100 Ω PRT/SPRT
100 Ω PRT/SPRT
-200
0
660
-200
0
232
5
25
84
20
100
185
0.0010
0.0040
0.0025
0.0040
0.0025
0.0020
200 - 1999.900 00 Ω
9.5 + 0.6
100 Ω PRT/SPRT
400
250
0.0025
Resistance Range
95% Confidence Level
0 - 199.990 000 Ω
200 - 1999.900 00 Ω
99% Confidence Level
Temperature Readout (Secondary Specifications)
[1] [2] [3]
Resistance Measurement Uncertainty
Temp Coeff. ± ppm Reading/°C
Transfer Uncertainty
20 Minute ±1 °C
[11]
±(ppm Reading + mΩ)
2-Wire
Adder
(Ω)
3-Wire
Adder
(Ω)
15 °C - 30 °C
5 °C - 15 °C
30 °C - 40 °C
0 - 199.990 000 Ω
0.8 + 0.14
0.1
0.005
0.6
1.0
200 - 1999.900 00 Ω
0.2 + 0.5
0.1
0.005
0.5
0.8
Resistance Range
Type ....................................................................... 4-wire current reversal resistance measurement with readout of
equivalent temperature. 2-wire and 3-wire selectable without current
reversal. Refer to Resistance specifications for additional details.
Temperature Range .............................................. -200 °C to 660 °C, readout also available in °F or K.
Linearization ......................................................... ITS-90 or Callendar van Dusen. Entry and storage of coefficients and
nominal resistance for up to 100 probes.
Current Source ..................................................... 1 mA
http://www.elso.sk
1-17
riešenia na presné meranie
8508A
Service Manual
Read Rate and Additional Uncertainty
Read Rate and Additional Uncertainty
Function
Resolution
DCV, DCI & Ohms
8
7
6
5
6
[10]
ACV & ACI
[6]
Filter
Frequency (Hz)
5
ACV Transfer Off
[6]
PRT & Tru Ohms
[14]
8
7
6
5
1
10
40
100
1
10
40
100
1
10
40
100
-
Read Rate
(readings/second)
[13]
Additional Errors
± (ppm Reading + ppm Range)
Normal
Fast
Normal
Fast
1/25
1/6
2
35
1/50
1/5
1/2
1
1/50
1/5
1/2
2
1/25
1/2.5
1
4
1/90
1/30
1/4
1/3
1/6
1/2
35
150
0+0
0 + 0.1
1.0 + 0.5
0+5
0+0
0+0
0+0
0+0
0+5
0+5
0+5
0+5
200 + 20
200 + 20
200 + 20
200 + 20
0+0
0 + 0.1
1.0 + 0.5
0+5
0 + 0.1
0 + 0.5
0 + 2.5
0 + 25
1/30
1/10
1/3
1/3
Notes to Performance Specifications
Fluke guarantees 8508A performance verification using specifications stated to 99 % confidence level.
[1] Specifications apply for max resolution in each function, normal mode
[2] Assumes 4 hour warm-up period
[3] Input zero or offset null required whenever the temperature moves more than ±1 °C from the temperature at which the previous
null/zero was performed
[4] TCal = Ambient calibration temperature
[5] Integration time >1 Power Line cycle
[6] Valid for signals >1 % Full Scale, Transfer Mode On. Signals must be DC coupled <40 Hz. Readings invalid with Transfer Mode On
and 1Hz filter selected when using internal trigger mode
[7] Max Volt.Hertz 3 x 107
[8] >300 V, <10 kHz add: ±0.0004 x (Reading-300)2 ppm
>300 V, 10 kHz - 30 kHz add: ± (0.0004 + (Frequency - 10000) x10-7) x (Reading-300)2 ppm
>300 V, >30 kHz add: ±0.0024 x (Reading-300)2 ppm
[9] Typical below 10 Hz for ACV, below 10 Hz and above 10 kHz for ACI, and above 2 GΩ for Resistance
[10] Tru Ohms mode available on 2 Ω to 20 kΩ ranges. Read Rate reduced in Tru Ohms Mode. Specification for Tru Ohms same as
corresponding Normal or Lo Current range
[11] Valid for 4-wire sensor
[12] Not including sensor uncertainty
[13] Assume Range and Full Scale = 2000 V when calculating for 1000 V Range. For DCI, additional errors only apply in 5 digit
resolution
[14] Fast mode not available in PRT
[15] The maximum display value for the Analog to Digital converter is 199 990 000 counts. This sets the maximum value measurable on
each range to be a one followed by four nines. For example, the maximum measured values on the 2 V range on DC Voltage are
±1.999 900 00 V. However, the 1000 V ranges are limited to a maximum 1050 V.
1-18
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Applying the Specifications
1
Applying the Specifications
Introduction
The Fluke 8508A has been designed specifically for metrologists. Not only does it
provide the performance metrologists need, but it is specified in a way to allow users to
really understand the uncertainties of the measurements, and easily make allowance for
those uncertainty contributions when performing measurement uncertainty analyses and
compiling uncertainty budgets. Contemporary metrology practices, including ISO17025
based laboratory accreditation schemes, require uncertainty analysis to be performed in
accordance with the statistically based techniques described in the ISO Guide to the
Expression of Uncertainty in Measurement (often referred to as the ‘GUM’). For
convenience, the 8508A specifications are quoted at a coverage factor of k=2, equivalent
to a confidence level of approximately 95 %, as required by these methods.
Specifications are also provided at a confidence level of 99 %.
Performance specifications for the 8508A consist of two elements, the first is a
contribution expressed as parts-per-million of the Reading, and the second contribution is
expressed as parts-per-million of the Range. These must be evaluated and combined for
the relevant reading and range values applicable to the measurement being made,
ensuring that both elements are evaluated on the same basis, such as parts per million of
the measured value or in absolute terms (volts, amps, ohms, etc). The two elements are
combined by adding algebraically. For example measuring 10 V on the 20 VDC range
and applying the 365 day
±1 °C specifications:
First, expressing the contributions in terms of parts-per-million of the measured value:
20 ⎞
⎛
= ± ⎜ 3.0 + 0.2 x
⎟ = ±(3.0 + 0.4 ) = ±3.4 ppm of 10 V
10 ⎠
⎝
Second, expressing the contributions in volts:
(
)
= ± 3.0 x 10 −6 x 10 + 0.2 x 10 −6 x 20 = ±3.4 x 10 −5 = ±34 μV
The 8508 is designed to provide accuracy and stability without the need for internal auto
or self calibration routines which may otherwise compromise the continuity and
traceability of measurement performance history. To realise the full potential of the
8508A performance accepted metrology practices should be employed, such as
performing a zeroing or null operation to remove any offsets present in the measurement
setup when making DC measurements. The 8508A specifications assume that these
methods are employed.
Absolute and Relative Specifications
The Relative to Calibration Standards specifications describe the performance of the
8508A itself for the time periods and temperature range listed excluding the uncertainty
of the standards used to perform calibration of the 8508A during manufacture. The
Absolute specifications include the uncertainty of the standards used to perform
calibration of the 8508A at manufacture and may be used to determine the uncertainty of
measurements made with the 8508A for periods up to 1 year and over a temperature
range of ±5 °C from calibration. If the user has their 8508A calibrated with different
uncertainties, the Relative specifications can be combined with the uncertainties
applicable to that calibration to determine the effective absolute uncertainty following
that calibration.
http://www.elso.sk
1-19
riešenia na presné meranie
8508A
Service Manual
Applying User’s Calibration Uncertainties
When the 8508A is calibrated by another laboratory the uncertainties of the calibration
standards used may be applied by combining those uncertainties with the 8508A’s
Relative to Standards specifications. The applicable calibration uncertainties and the
8508A relative specifications must both be expressed at the same confidence level, and
be combined in a RSS (Root Sum Square) summation. Accepted metrology practice
mandates that calibration uncertainties are stated at 95 %. Check the applicable
calibration uncertainties are stated at 95 % and then combine them with the 8508A 95 %
Relative specifications. For example, if the 8508A is calibrated at 10 V DC with an
uncertainty of 1.5 ppm at 95 %: The absolute uncertainty at 10 V for a period of 90 days
and ±1 °C from calibration is:
2
20 ⎞
⎛
= ± 1.5 + ⎜1.4 + 0.2 × ⎟ = ± 2.3 ppm of 10 V
10 ⎠
⎝
2
Operating and Calibration Temperature Ranges
As a metrology tool, the 8508A will commonly be used in a calibration laboratory where
the temperature would be controlled to ±1 °C, and the 8508A ±1 °C specifications are
applicable to those situations. The majority of electrical calibration laboratories operate at
a nominal temperature of 23 °C, the temperature at which the 8508A is calibrated by
Fluke during manufacture and service. The 8508A is also capable of being calibrated at
any temperature between 20 °C and 25 °C and the ±1 °C specifications will apply to
operation within ±1 °C of that calibration temperature. In the 8508A specification tables
the temperature of calibration is referred to as TCal. Specifications for ±5 °C are
provided for situations where the 8508A is operated in environments with wider
temperature variations up to ±5 °C. For applications where the knowledge of the effect of
temperature on 8508A performance is important, temperature coefficients are listed in the
8508A specifications. If the operating temperature is within the range 15 °C to 30 °C the
15 °C to 30 °C temperature coefficient specifications are applicable otherwise use the
5 °C to 15 °C/30 °C to 40 °C figures, provided the temperature lies within that range. The
8508A may be operated at temperatures between 0 °C and 50 °C, but performance is not
specified outside the range 5 °C to 40 °C.
Applying Temperature Coefficient Specifications
The 8508A specification tables include information for the typical operating conditions
of ±1 °C for calibration laboratories with tight temperature control, and ±5 °C for
calibration laboratories with looser temperature control or uncontrolled environments
within that temperature range. For the majority of applications choosing the Absolute
specifications for the most appropriate operating temperature range will be adequate.
However performance at other temperatures may be determined by including an
allowance for temperature coefficient over the additional temperature range. Care should
be taken when making this calculation as an amount of temperature coefficient is already
included in the 8508A specifications and those specifications are themselves based on
combining contributions using techniques similar to those employed in uncertainty
analysis. For example, consider operating at 33 °C, 10 °C from the 23 °C calibration
temperature. The ±5 °C specifications already include a contribution for 5 °C of
temperature difference, so this amount of temperature effect must be removed before the
effect of the 10 °C difference is added. Consider 10 V on the 20 VDC range: 365 day
absolute specification (95 %) at 33 °C expressed in parts-per-million of 10 V is:
2
20 ⎞
⎛
2
2
= ± ⎜ 3.5 + 0.2 × ⎟ − (5 x 0.3) + (10 x 0.5) = ± 6.16 ppm of 10 V
10 ⎠
⎝
1-20
http://www.elso.sk
riešenia na presné meranie
Introduction and Specifications
Applying the Specifications
1
Ratio Measurements
The 8508A Ratio mode will automatically take measurements of inputs applied to the
front and rear terminals and display the result as a ratio in the voltage and resistance
functions. The measurements can be made on the same range or different ranges. When
making measurements on different ranges the error in each measurement is evaluated by
applying the relevant specification for each range and combining the two specifications in
an RSS summation, expressing the contributions in parts-per-million of the measured
values. For example, making measurements of the ratio of 100 mV on the 200m VDC
range and 100 V on the 200 VDC range, applying the 365 day ±1 °C Absolute
specifications:
2
2
⎛
200 x 10 −3 ⎞ ⎛
200 ⎞
⎟ + ⎜ 4.5 + 0.2 x
= ± ⎜⎜ 4.5 + 0.5 x
⎟ = ± 7.37 ppm of the ratio
−3 ⎟
100 ⎠
100 x 10 ⎠ ⎝
⎝
Making measurements on the same range will eliminate range to range errors, such as
drift since the time of calibration, and improve the result. When making measurements on
the same range these errors will affect both measurements and effectively cancel, leaving
short term noise and linearity as the dominant errors. The 20 minute Transfer Uncertainty
Specifications are provided to describe the performance obtained when making ratio
measurements on the same range. The error in each measurement is evaluated by
applying the relevant 20 minute Transfer Uncertainty Specification for each value and
combining the two specifications in an RSS summation, expressing the contributions in
parts-per-million of the measured values. If the measurements are made within the same
range, but independently (not using the ratio mode) with an elapsed time greater than 20
minutes but less than 24 hours between the measurements, then the 24 hour specifications
should be applied instead.
For example, making measurements of the ratio of 5 V and 10 V on the 20 VDC range,
applying the 20 minute Transfer Uncertainty specifications:
2
2
20 ⎞
20 ⎞ ⎛
⎛
= ± ⎜ 0.12 + 0.1 x
⎟ = ± 0.61 ppm of the ratio
⎟ + ⎜ 0.12 + 0.1 x
10 ⎠
5 ⎠ ⎝
⎝
Additional Errors
The 8508A specifications are listed for the maximum resolution in each function, using
the Normal reading mode. For measurements taken in other resolutions or the Fast read
mode additional error contributions listed in the Read Rate and Additional Uncertainty
table must be included. These additional contributions must be added algebraically to the
relevant specifications. For example measuring 10 V on the 20 VDC range at 5 digit
resolution in Fast mode and applying the 365 day ±1 °C Absolute specifications:
20 ⎞
⎛
= ± ⎜ (3.0 + 0) + (0.2 + 25) x
⎟ = ±(3.0 + 50.4 ) = ±53.4 ppm of 10 V
10 ⎠
⎝
Other additional contributions apply in certain situations and are also to be added
algebraically to the relevant specifications. These additional contributions include the DC
Accuracy specification to be applied when making DC measurements on the AC Voltage
function when DC coupled, and the High Voltage adder when making measurements
above 300 V on the AC Voltage function.
http://www.elso.sk
1-21
8508A
Service Manual
1-22
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
Chapter 2
Theory of Operation
Title
Introduction..........................................................................................................
Overall Functional Description............................................................................
Main Assemblies .............................................................................................
Power Supplies ................................................................................................
http://www.elso.sk
Page
2-3
2-3
2-3
2-6
2-1
8508A
Service Manual
2-2
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
Theory of Operation
Introduction
2
Introduction
This chapter provides a board-level theory of operation for the 8508A Reference
Multimeter. Functional block diagrams supplement the text when appropriate. In addition
to providing a conceptual overview of the Multimeter’s operation, the descriptions are
helpful for troubleshooting and isolating problems to a board level.
Reference Designators are used throughout this chapter to identify the major Printed
Circuit Assemblies (PCAs) used in the Multimeter. These reference designators also
appear in the List of Repaceable Parts (Chapter 5) to simplify the process of purchasing
replacement modules and PCAs.
Overall Functional Description
Main Assemblies
Refer to the functional block diagram shown in Figure 2-1 while reading this description.
In addition to identifying all of the assemblies contained in the Multimuter, this diagram
provides a functional view of the data flow between the assemblies. Assembly
interconnections and cable identification is detailed in chapter 4, Maintenance.
The following list identifies the six major assemblies contained in the Multimeter and
includes a description of the basic functions each assembly performs:
A1
DC PCA
Optical isolation; measurement configuration; V dc, I dc and I
ac measurements
A2
AC PCA
True-rms measurement
A3
Ohms PCA
Resistance measurements: 2-wire, 4-wire, high-voltage,
ratio, etc.
A4
Digital PCA
Out-guard power supplies, control of IEEE (GPIB) and serial
data (measurement and control)
A5
Bezel Assembly
Front panel user interface, display and keyboard, includes
the A5A1 Display PCA.
A6
Rear Input Assembly
(optional)
Rear input connections, includes the A6A1 Rear Input PCA.
Normal operator interaction with the Multimeter begins at the front panel (A5) which
includes a keyboard for entering measurement configurations (functions, ranges, etc.) and
a display for verifying the selected configurations and for displaying measurement
results. Both the keyboard switches and the display are included on the A5A1 Display
PCA. A rubber keypad, whose keys include a conductive backing, provides switching
information to A5A1. A controller on the A4 Digital PCA provides the addressing,
strobing, and storage of data coming from and going to the A5A1 Display PCA. The data
stored on the A4 Digital PCA includes both the manually entered configuration data for
use by the display and other assemblies, as well as, the resulting measurement data for
use by the display as measurement results.
Before being used by the Multimeter, the stored configuration data is converted on the
A4 Digital PCA from a parallel to serial format. Similarily, the A4 Digital PCA receives
serial measurement data from the instrument and converts it to a parallel format for use as
display data. A rear panel IEEE-488 (GPIB) bus is intergrated into the format conversion
process.
http://www.elso.sk
2-3
riešenia na presné meranie
8508A
Service Manual
A3 Ohms PCA
Input Select
I to R Converter
2-Wire
4-Wire
Range
-15 V
A2 AC PCA
Input Select
Range Selection
Rectifier
Input Select
DC
Preamp
Input Select
10:1
I DC
and
I AC
Lo-Pass
Filter
Output
Buffer
A1 DC PCA
Range Selection
DC V
RMS
Converter
AC
Preamp
Internal Bus
Input Signal Bus
AC
AC + DC
DC AMP
(Chopper
Stabilized)
A to D
Converter
(ADC)
AD MUX
In-guard
Power Supplies
250 VAC
+5 V
+8 V
+15 V
–8 V
+36 V
Internal
Reference
Range Switched
Precision Shunts
In-guard
Out-guard
A4 Digital PCA
Out-Guard Power Supply
+5 V +8 V, +17 V
Input Signal
Switching Relays
Relay Control and
Relay Drivers
Optically Isolated
Serial Interface
Keyboard and
Display Memory
A6 Rear Input
Assembly
IEEE (GPIP)
to
Serial
Line
Power
Rear Panel
IEEE-488
(GPIB)
A5 Bezel Assembly and
A5A1 Display PCA
avw003f.eps
Figure 2-1. 8508A Functional Block Diagram
2-4
http://www.elso.sk
riešenia na presné meranie
Theory of Operation
Overall Functional Description
2
A 16-pin cable (W3) enables serial control and measurement data to move between the
A4 Digital PCA and the A1 DC PCA. Opto-isolators on the A1 DC PCA optically isolate
the external control and display circuits of the Multimeter from the measurement circuits.
This isolation minimizes problems associated with noise and current loops in the
measurement circuits. Throughout this chapter, this isolation is referred to as in-guard
(measurement circuits) and out-guard (control and data transfer circuits).
Control data from the A4 Digital PCA passes through the opto-isolators and serves as
input to a series of tri-state latches. These latches retain the control data, and they provide
the input to a series of relay drivers, which in turn drive a series of configuration relays.
These relays establish the necessary connections between the various assemblies to
perform the measurement called for from the front panel keyboard (or GPIB inputs).
These relays also route analog data (and associated guarding) from the input terminals
(front and rear) to the appropriate assemblies as defined by the measurement control data.
The A1 DC PCA, in addition to switching the measurement configurations and the
routing of input and measurement signals, includes the circuits to perform the following
functions:
• DC measurements
Handles both DC voltage and dc current measurements
• Analog to digital conversion (ADC)
The ADC processes all measurement data (volts, ohms, and current) before routing it
(in digital form) to the A4 digital PCA for display and GPIB access.
• Current to voltage conversion
Both the ac and dc current measurement functions (IDC and IAC) use the same
current shunts.
• Self-Test
Produces a variety of reference signals from -10 to +10 volts and places them on the
internal signal bus for measurement and display. These tests provide a high degree of
certainty that the Multimeter is functioning correctly, and they are useful for
troubleshooting to the board level.
The A2 AC PCA performs the ac voltage and ac current measurements. The ac voltage
portion of the assembly includes an associated collection of range, configutation, and
filter circuits, as well as an ac preamplifier, and an rms-to-dc converter. The output of the
rms-to-dc converter is a dc voltage proportional to the true-rms value of the input signal.
The multiplexer on the A1 DC PCA receives the dc voltage and routes it to the ADC
(Analog-to-Digital Converter) which, in turn, sends the digital results to the opto
isolators. The opto isolators couple the digital data to the A4 Digital PCA for access by
the display and GPIB.
The A1 DC PCA provides the configuration control required to connect the ac input
signal to the A2 AC PCA. For ac voltage measurements the input signal is routed in
much the same manner as a dc measurement signal. For ac current measurements, the ac
input current is routed through the same set of current shunts used to make dc current
measurements. To measure the ac current, the A2 AC PCA measures the voltage drop
across the shunt and sends the results to the A4 Digital PCA as when making an ac
voltage measurement.
The A3 Ohms PCA performs 2-wire, 4-wire, high-voltage, and ratio measurements. All
of these measurements derive the unknown resistance value by passing a constant
stimulus current through the unknown resistor and measuring the resulting voltage drop
-n
across it. By limiting the current to a value of 1X10 , the voltage drop is equal to the
resistance value, e.g., 1 mA through 2.12 kΩ = 2.12 V. To accommodate range changes,
the reference current changes to match the selected range. The reference current starts at
2nA for the 2 GΩ range and increases to .1 mA for the 2 Ω range. A high-gain inverting
amplifier with low-input current and low-offset voltage performs the voltage
http://www.elso.sk
2-5
riešenia na presné meranie
8508A
Service Manual
measurement across the unknown resistor. Configuration relays on the A1 DC PCA
perform the change in terminal connections between two- and four-wire measurements.
The A3 Ohms PCA includes an alternative high-resistance measurement feature for
resistance measurements above 20 MΩ. These measurements use 10 times the standard
stimulus current and result in a 10 times increase in the voltage across the resistor. This
high-voltage resistance feature enables the Multimeter to make quiter and faster
measurements. It also enables the inclusion of a 20 GΩ resistance range.
Another feature included on the A3 Ohms PCA is true-ohms. This feature eliminates the
input offset-voltage from the measurement circuit by continuously reversing the direction
of current flow through the unknown resistence. The stimulus current reversal is timed so
that the current flows continuously thus maintaining identical and constant self-heating of
the unknown in both forward and reverse measurements. To ensure same-polarity
measurements, voltage sensing of the unknown resistor synchronously reverses with the
current.
The true-ohms ratio function uses a similar current reversal process. However, the current
is applied to both unknown resistors simultaneously.
Power Supplies
The Multimeter has two types of power supplies, out-guard supplies and in-guard
supplies. The out-guard supplies provide power for the digital (earth ground) side of the
Multimeter. This includes the A4 Digital PCA, the A5A1 Display (and keyboard), and
the opto couplers on the A1 DC PCA. The in-guard supplies provide power for the analog
(measurement) side of the Multimeter. This includes the A1 DC PCA, the A2 AC PCA,
and the A3 Ohms PCA.
Two chassis-mounted transformers (T1 and T2) are the source of all the various voltages
required for operation of the Multimeter. See Figure 2-2. Transformer T2 is the fused
line-powered (mains) transformer. It has a single 24 V center-tapped secondary which
provides ac power for both the out-guard and in-guard power supplies. On the A4 Digital
PCA, the 24 V ac drives three conventional rectifiers and regulators to provide +5 V,
+8 V, and +17 V sources for the out-guard circuits. The +5 and +8 volts provide power
for out-guard digital logic circuits; the +17 volts, along with a driver on the A4 Digital
PCA, supplies the power (17 V ac) to drive the primary of the in-guard transformer T1.
Transformer T1 has 3 secondaries which drive a series of conventional rectifiers and
regulators located on the A1 DC PCA. These T1 supplies provide the following in-guard
operating voltages:
•
•
•
•
•
+5V dc regulated
+8 V dc un-regulated
±15 V dc regulated
±36 V dc regulated
250 Vac
All of the in-guard PCAs use these in-guard voltages, with the exception of the 250 V ac
which goes directly to the A3 Ohms PCA where it is rectified and filtered for use in
making the high-voltage ohms measurements. The 250 V dc supply is active only when
the High Voltage Ohms function is selected.
A few other in-guard voltages, which are uniquely developed and used on the A3 Ohms
PCA, include +5 V, -15 V, ±6 V, and +5.5 V. The in-guard voltages on the A1 DC PCA
are the original source driving all of these uniquely developed voltages on the A3 Ohms
PCA.
2-6
http://www.elso.sk
riešenia na presné meranie
Theory of Operation
Overall Functional Description
2
T1 J150
J401
250 V ac
to
Ohms
PCA
J502
+
+15 V regulator
+15 V dc
15 V regulator
-15 V dc
-
+17 V
-18 V dc
+
-
+36 V regulator
+36 V dc
36 V regulator
-36 V dc
+8 V dc
+5 V regulator
+5 V dc
In-guard Voltages
Out-guard Voltages
F1
T2
J501
Line
Power
+17 V regulator
+17 V dc
+8 V regulator
+8 V dc
+5 V regulator
+5 V dc
avw004f.eps
Figure 2-2. Power Supplies - Simplified Block Diagram
http://www.elso.sk
2-7
8508A
Service Manual
2-8
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
Chapter 3
Calibration and Verification
Title
Introduction..........................................................................................................
Calibration Overview...........................................................................................
Calibration Interval and Performance ..................................................................
Calibration Points ................................................................................................
Non-Nominal Values.......................................................................................
Enabling Access to Calibration Mode .................................................................
Calibration Menus................................................................................................
Accessing the Calibration Menus and Calibration Mode ................................
Calibration Menu.............................................................................................
SET VALUE Menu .........................................................................................
SPOT CAL Menu ............................................................................................
SPOT (1 to 6) RMS Menus .............................................................................
SPOT FREQUENCY (1 to 6) Menu ...............................................................
Special Calibration ..........................................................................................
SPCL Menu .....................................................................................................
SER # = Menu .................................................................................................
Hvlin Menu......................................................................................................
Non-volatile input offset compensation...............................................................
Routine Calibration..............................................................................................
Equipment Required for Calibration ...............................................................
Preparing for Calibration .................................................................................
Interconnections ..............................................................................................
ADC Calibration..............................................................................................
DC Voltage Calibration ...................................................................................
AC Voltage Calibration ...................................................................................
Resistance Calibration .....................................................................................
DC Current Calibration ...................................................................................
AC Current Calibration ...................................................................................
Frequency Calibration .....................................................................................
Exit From Calibration Mode and Non-Volatile Input Offset Adjustment.......
Cal Due Date Entry and Calibration Mode Disable ........................................
ACV Spot Frequency Calibration........................................................................
Performance Verification.....................................................................................
Equipment Requirements ................................................................................
Interconnections ..............................................................................................
http://www.elso.sk
Page
3-3
3-3
3-3
3-3
3-4
3-4
3-4
3-4
3-4
3-5
3-6
3-6
3-6
3-7
3-7
3-7
3-8
3-8
3-9
3-10
3-10
3-11
3-14
3-14
3-16
3-18
3-25
3-27
3-28
3-29
3-30
3-30
3-31
3-32
3-32
3-1
8508A
Service Manual
riešenia na presné meranie
Applicable Verification Tolerance and Conditions .........................................
Preparation.......................................................................................................
DC Voltage Checks .........................................................................................
AC Voltage Checks .........................................................................................
Resistance Checks ...........................................................................................
DC Current Checks..........................................................................................
AC Current Checks..........................................................................................
Frequency Checks ...........................................................................................
3-2
http://www.elso.sk
3-32
3-33
3-33
3-35
3-37
3-40
3-41
3-43
riešenia na presné meranie
Calibration and Verification
Introduction
3
Introduction
This chapter describes the calibration menus, and lists the calibration and performance
verification procedures for the Multimeter. Remote commands for calibration of the
Multimeter are described in Chapter 4 of the Users Manual, Remote Operations using the
IEEE 488 Interface. In this chapter, menu and button selections are shown as all-caps
text.
Calibration Overview
An electronic autocal feature allows full calibration of all functions of the Multimeter
from the front panel (or remotely via the IEEE 488.2 Interface). No hardware adjustments
are necessary.
For each combination of function and range, an appropriate calibration standard (source)
is input. At each setting, one keystroke immediately calibrates to the standard by
updating an internal non-volatile calibration memory. The Multimeter automatically
determines whether the operation is to be a Zero or Range Gain calibration; or for AC
ranges whether it is to be a Zero, LF Gain or HF Gain calibration. As part of the
calibration procedure, a non-volatile input-offset compensation is adjusted independently
for the front and rear inputs. The autocal process can operate only when the rear panel
Calibration switch is in the ‘Enable’ position. Applying an integrity seal or calibration
sticker to prevent access to the rear panel Calibration switch is a convenient way to
ensure the security of calibration. When a calibration operation is performed the
Multimeter’s internal calibration memory is immediately updated. It is possible to
calibrate a single range or single point if the user chooses to do so. However, it is
recommended that the calibration procedure listed later in this chapter be followed
closely.
Calibration Interval and Performance
It is recommended that the Multimeter be calibrated on either a 365-day or 90-day
interval depending on the requirements of the applications for which the Multimeter is
used and the performance specifications required. The performance of the Multimeter is
specified for periods of 365 days and 90 days – if recalibration takes place on a 90-day
cycle use the 90-day specifications for improved performance.
During manufacture, the Multimeter is calibrated with low uncertainties, reflected in the
Absolute Specifications listed in Chapter 1 Introduction and Specifications. After
recalibration, the user should apply the calibration uncertainties for the calibration
standards and for the process applicable to that calibration by combining those calibration
uncertainties with the Multimeter Relative to Standards specifications, as described in
Chapter 1.
Many Multimeter owners prefer using Fluke calibration services instead of maintaining
their own standards to support their Multimeter.To help ensure optimum performance
from the Multimeter, Fluke offers our calibration service at a variety of worldwide
locations. Our worldwide service network provides fast efficient calibration to ensure low
uncertainties and optimum accuracy consistent with the original calibration at
manufacture.
Calibration Points
There is generally more than one calibration point for each range. An initial measurement
(made when the calibration is triggered) determines the intended calibration point. The
points for each range and function are listed later in this chapter.
http://www.elso.sk
3-3
riešenia na presné meranie
8508A
Service Manual
Non-Nominal Values
The Set facility allows the user to set the calibration target to the value of the calibration
source available. This facility is most useful when the user’s calibration source is not
available at the nominal values specified, or when the user has knowledge of the actual
output of the calibration source at the required points. In these cases, the use of the Set
facility with a table of errors for the calibration source is recommended and will improve
the accuracy of the Multimeter’s calibration.
Enabling Access to Calibration Mode
The setting of a Calibration-switch on the rear panel enables or restricts access to the
calibration mode. Setting the switch to ENABLE allows access to the calibration mode via
the front panel CAL key and the CALIBRATION menu, and also enables the remote IEEE
488 interface calibration commands. Setting the switch to DISABLE and applying an
integrity seal or calibration sticker to cover the Calibration switch is a convenient way to
ensure the security of calibration and to prevent unauthorized access to the switch.
Calibration Menus
Accessing the Calibration Menus and Calibration Mode
Pressing the CAL key on the front panel causes the Multimeter to respond as follows:
1. Enters the calibration (CAL) mode
2. Displays and allows access to the CALIBRATION menu
3. Displays the CAL legend on the main display
To exit the CALIBRATION menu Press the Quit softkey. On exit the Multimeter
displays the prompt to enter a calibration due date.
When in CAL mode the following front panel keys become inoperative: CLR, TEST,
OFFSET, PRT and INPUT. Also the function of the SAMPLE key changes to become the
trigger key for initiating a calibration operation.
W Caution
When in CAL mode with the CAL legend appearing on the main
display the function of the SAMPLE key is modified from
normal operation. If pressed, the SAMPLE key will initiate a
calibration operation and permanently alter the Multimeter’s
calibration state. To avoid accidental mis-calibration do not
attempt to operate the Multimeter in External Trigger mode from
the front panel when in Cal, and only press the SAMPLE key
when a calibration operation is intended to be performed.
Calibration Menu
This menu allows calibration operations at the calibration point nominal values via Auto,
or selection of calibration operations at non-nominal values via Set. It also offers access
to the special calibration menu. The CAL legend appears in the left-hand display when in
CAL mode.
adj134f.eps
CALIBRATION Menu
3-4
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Calibration Menus
3
This menu defines four menu keys:
Auto
Indicates to the user that the calibration point is automatically set according
to the amplitude (and frequency in ACV) of the signal detected. Auto is the
default selection on entry to the CALIBRATION menu. Refer to the tables
appearing later in this chapter for the calibration points for the selected range.
An indication of the use of the SAMPLE key is also displayed
Set
The Set feature is available in all functions, allowing the user to enter the true
value of the calibration standard where it differs from nominal calibration
point value. Pressing Set displays the SET VALUE menu except in ACV Spot
Frequency mode, when the SPOT CAL menu is displayed. Spot Frequency
calibration reduces flatness errors within ± 10 % of the spot frequency. Set is
not available for DCV, DCI, and Resistance range zero calibrations.
Special Special Cal is indicated on the main display. The SPCL menu is displayed
which allows pre-calibration of the Multimeter, calibration of the frequency
counter, and entry to other calibration utilities.
Quit
Exits from the CALIBRATION menu via the CALIBRATION DUE ? menu,
where the recommended next calibration date can be entered, before finally
quitting the calibration mode.
SET VALUE Menu
This menu is obtained by pressing the Set key in the CALIBRATION menu on all
functions except ACV Spot Frequency.
adj139f.eps
SET VALUE Menu
When this menu appears, it shows the nominal calibration point value, allowing the user
to enter the true output value of the calibration standard at the point to be calibrated. The
keyboard is activated, locking out all other keys. The Set value is entered in exponential
format expressed in Volts, Amps, or Ohms, and must be above 20 % of range (40 % on
the 1000V DCV and ACV ranges). The SAMPLE key has no effect until the Set value is
stored by pressing the Enter key.
The Multimeter always chooses the most-recently stored Set value when calibrating. Set
is not available for DCV, DCI, and Resistance range zero calibrations.
W Caution
Enter: The new value is stored and the keyboard is deactivated. The set value remains on the dot-matrix display for
comparison with the reading on the main display after the
SAMPLE key has been pressed.
Quit: Reverts to the CALIBRATION menu, deleting the set
value from store.
http://www.elso.sk
3-5
riešenia na presné meranie
8508A
Service Manual
SPOT CAL Menu
This menu is obtained by pressing the Set key in the CALIBRATION menu when the
Multimeter is in ACV Spot Frequency mode. It provides a means of calibrating the
Multimeter at any of six user-specific spot frequencies, at non-nominal calibration values
for each ACV range. The Multimeter will already be set to an ACV range on entry to the
menu.
adj140f.eps
SPOT CAL Menu
This menu allows a user to select a spot frequency (Spx) for the selected range. It defines
six menu keys:
Sp1:
Displays the SPOT 1 RMS menu, where users define the RMS value for
the Spot Frequency 1 calibration point on the currently selected range.
Sp2-6:
Same as Sp1 but permitting their own RMS values to be defined.
SPOT (1 to 6) RMS Menus
On entry to one of the six SPOT (x = 1 to 6) RMS menus, the nominal cardinal point
value is displayed and the keyboard is activated. A numeric value can be entered that
represents the RMS value of the calibration source signal.
adj141f.eps
SPOT n RMS Menus
Enter
Stores the displayed RMS value and de-activates the keyboard.
The dot-matrix display moves to the SPOT FREQUENCY (1 to 6) menu,
showing the calibration signal frequency.
Quit
Reverts to the SPOT CAL menu, not storing any new Spot value.
Note
The SAMPLE key is still enabled in the next menu.
SPOT FREQUENCY (1 to 6) Menu
Enter this menu by pressing Enter in the SPOT (1 to 6) RMS menu, which also stores the
RMS value keyed in during this menu. The value in the SPOT FREQUENCY (1 to 6)
menu is the measured frequency of the present calibration input signal.
adj142f.eps
SPOT FREQUENCY n Menu
Pressing the SAMPLE key causes the selected ACV range to be spot-calibrated at the
calibration signal frequency. The frequency value is stored and can be viewed from the
UTILITY menu. Any subsequent measurement on this range whose frequency is within
3-6
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Calibration Menus
3
±10 % of the stored frequency is accuracy enhanced by reducing frequency response
flatness errors.
Calibrate the spot at a new frequency:
To calibrate the spot at a new frequency, change the input signal to the desired new
frequency and press SAMPLE as before.
Quit
Reverts to the SPOT CAL menu with the original Spot calibration intact.
Special Calibration
The SPCL menu provides alignment of the main ADC and calibration of the frequency
counter.
It also allows the High Voltage Linearity Pre-Calibration to be performed and a section of
the Non-Volatile memory to be cleared for test purposes. These facilities are used in the
factory for initial pre-calibration processes; they should not require access during the life
of the Multimeter unless repairs have been carried out. They appear here for
completeness.
SPCL Menu
The SPCL menu appears after pressing the Spcl key in the CALIBRATION menu. At
the same time the Multimeter is placed in special calibration mode, and the Special CAL
legend appears on the main display.
When in Special CAL mode the following front panel keys remain inoperative: CLEAR,
TEST, OFFSET, PRT and INPUT. Also, the function of the SAMPLE key changes to
become the trigger key for initiating the Hvlin calibration operation.
adj137f.eps
SPCL Menu
The SPCL menu provides the selection:
Ser#
Adc
Freq
Hvlin
ClrNv
Quit
Permits entry of the Multimeter’s serial number.
Aligns the different resolutions available from the Multimeter's main analogto-digital converter, so that there are no significant differences in readings
when changing resolutions with a constant input value. No external input
signals are required for this calibration. Calibration is initiated directly by
making this selection from the SPCL menu.
Calibrates the frequency counter against an external source. Calibration is
initiated directly by making this selection from the SPCL menu.
Selects the sequence required to correct the linearity of the 1kV DC range.
Provides the capability to clear a section of the non-volatile memory for ‘test
purposes only’.
Reverts to the CALIBRATION menu.
SER # = Menu
This menu is obtained by pressing Ser# in the SPCL menu. On entry to the menu, the
most-recently-entered serial number is shown, and the keyboard is activated. A numeric
value can be entered.
http://www.elso.sk
3-7
riešenia na presné meranie
8508A
Service Manual
adj138f.eps
SER# Menu
The SER# menu provides the selection:
Enter
Stores the new serial number, de-activates the keyboard, and reverts to the
SPCL menu.
Quit
Reverts to the SPCL menu, leaving the old serial number intact.
Hvlin Menu
This menu sequence is obtained by selecting Hvlin from the SPCL menu. It allows the
linearity of the 1kV DC range to be calibrated with the application of five input signals of
-1000V, -500V, 0V, +500V and +1000V in turn, with the 1kV DC range selected. On
entry to the menu, the user is prompted to apply the first input signal required and step
through the sequence:
adj135f.eps
Hvlin Menus
Pressing the SAMPLE key initiates the calibration operation at the signal level displayed
for the step in progress and; also, saves the result for calculation of the Hvlin linearity
correction factor at the end of the sequence.
PREV
Moves back to the previous menu allowing the user to repeat the previous
step in the sequence if required.
NEXT
Moves forward through the sequence to the next step and signal level.
CALC
Initiates calculation and storage of the high voltage linearity correction
factor, completing the Hvlin calibration process.
Non-volatile input offset compensation
Good metrology practice should ensure that all high-precision measurements made with
the Multimeter are preceded by an input zero of each measurement. However, a nonvolatile input-offset compensation is independently available for the front and rear inputs
and will be used whenever the input zero capability is not in use. The compensation is
retained after power down, is unaffected by clearing the volatile input zeros, and is
unaffected by range zero calibration adjustments. Compensation is available on all
functions, and includes separate compensation of 2-wire and 4-wire measurements in the
resistance functions.
3-8
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Non-volatile input-offset compensation adjustment is available only when the rear panel
calibration keyswitch is in the ENABLE position and the CAL legend is not shown on the
main display.
Adjustment is performed by initiating an input zero operation with the Multimeter in this
condition, using the INPUT menu as described in Chapter 3 or using the IEEE 488 input
zeroing commands described in Chapter 4. Appy a high-integrity low-thermal emf 4-wire
short to the input terminals for this operation. Following adjustment for a particular
combination of function, range, and input a compensation is also stored for the
corresponding volatile input zero, and the Zero legend is shown on the main display. The
Zero legend may be removed from the display without affecting the stored non-volatile
compensation by using one of the following operations:
1. Power the Multimeter down.
2. Press the CLEAR key and make any of the selections from the CLEAR menu.
3. Press the CAL key and entering CAL mode.
4. Use the corresponding IEEE 488 commands.
Routine Calibration
The 8508A Digital Reference Multimeter offers state-of-the-art performance. This
procedure is intended as a guide for qualified metrology personnel who have access to a
standards laboratory with equipment available to support an Multimeter of this level of
accuracy. It reflects the calibration process used by Fluke to perform Multimeter
calibration implemented in an automated system, but as a manual procedure for users to
follow. The procedure is based on the following assumptions:
1. Users are familiar with relevant best measurement practice.
2. Users will take precautions to avoid introducing errors from sources such as thermal
emfs, leakages, electromagnetic interference, etc.
3. Users will make adequate allowance for equipment stabilization and measurement
settling times.
This routine calibration procedure describes the calibration points and sequence of
operations required to calibrate the Multimeter and assumes calibration references of
adequate traceable uncertainty are available – in this case a Fluke 5720A calibrator and
5725A amplifier used with an 8508A-7000 Calibration Kit. The procedure assumes the
user is able to calibrate and characterize the calibration standards, without describing the
process required to do so.
Characterization of the 5720A/5725A combination allows the 8508A to be calibrated
with uncertainties lower than otherwise available from that equipment. The
characterization process determines the 5720A/5725A errors from nominal at the values
required for 8508A calibration, and may be performed using Fluke’s recommended
verification procedures appearing in the 5700A/5720A Service Manual as a guide. If a
characterized 5720A/5725A combination is available where the error from nominal at the
various points required is known, those errors may be taken into account during
calibration to reduce the uncertainties. The errors may be determined by measurement
against suitable standards or may be taken from an applicable certificate of calibration.
The uncertainty of the characterized calibrator should be combined with the Multimeter
Relative to Standards specifications to determine Multimeter performance after
calibration. (RSS summation is recommended).
If the calibrator is not characterized to determine its errors from nominal, its output
should be assumed to be nominal at all points. Its performance specifications should be
http://www.elso.sk
3-9
riešenia na presné meranie
8508A
Service Manual
used to provide calibration uncertainties to be combined with the 8508A Relative to
Standards specifications to determine the achieved Multimeter performance after
calibration. (RSS summation is recommended).
See Chapter 5 for more details of combining 8508A Relative to Standards specifications
and calibration uncertainties.
Note
The Multimeter should be thoroughly checked to ensure it is operating
correctly before attempting calibration. A performance verification
procedure appears later in this section.
Equipment Required for Calibration
The equipment required for Calibration and Performance Verification is listed in
Table 3-1.
Table 3-1. Required Equipment for Calibration Adjustments and Performance Verification
Equipment Name
Minimum Use
Specifications
(ranges and accuracy)
Recommended Models
Multifunction Calibrator [1] [2]
Fluke 5720A
Amplifier [2]
Fluke 5725A
Signal Lead Set
Fluke 5440-7003, -7004, -7005
Calibration Kit
One 1 GΩ Standard, two
precision low thermal emf
4-wire shorting devices, and
connecting leads.
Fluke 8508A-7000K
PC/Network Printer/ Cables
PC/Network Printer/ Cables
Any
Metrology bd software
Fluke MetBase
Metrology Calibration Software
Fluke Metcal v6.11 or later
[1] Availability of a 1 MHz frequency reference signal may be required for 5720A frequency locking during 8508A frequency
calibration procedure.
[2] Best uncertainties are obtained by characterizing the outputs of the 5720A and 5725A at the points used for 8508A calibration.
Alternate equipment may be used, but users should ensure it provides adequate
calibration uncertainties. Performance of the Multimeter after calibration should be
determined by combining the applicable calibration uncertainties provided by the
calibration equipment with the 8508A Relative to Standards specifications. (RSS
summation is recommended).
Preparing for Calibration
The following procedures represent the recommended order of calibration, giving all the
necessary setup commands.
1. Allow the Multimeter to warm-up under power in the specified environment for at
least 4 hours.
2. Press the CLEAR key, select Pwr Up Dflt to restore the power up default configuration
and display the DCV menu.
3-10
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
3. Set the rear panel Calibration switch to Enable. Removal of any calibration sticker or
integrity seal covering the calibration switch will be necessary.
4. Press the CAL key.
5. The CALIBRATION menu is displayed.
The calibration menu appears, and the CAL legend appears on the main display. When
entering CAL mode and selecting a function the optimum resolution for performing
calibration in that function is automatically selected. Refer to Table 3-2 for the full
multimeter calibration sequence.
Note
It is recommended that the default resolutions are used for calibration purposes. Other
resolutions may be selected and calibration operations performed, but accuracy of
calibration will be degraded if calibration is performed in lower resolutions.
W Caution
When in CAL mode with the CAL legend appearing on the main
display, the function of the SAMPLE key is modified from
normal operation. If pressed, the SAMPLE key will initiate a
calibration operation and permanently alter the Multimeter’s
calibration state. To avoid accidental mis-calibration do not
attempt to operate the Multimeter in External Trigger mode from
the front panel when in Cal, and only press the SAMPLE key
when a calibration operation is intended to be performed.
Table 3-2. Calibration Sequence
General Sequence for Full Multimeter Calibration [1]
Enable Calibration
Enter Cal mode
Adc Cal
DCV
ACV
Ohms
DCI
ACI
Frequency
Exit Cal mode
NV input offsets
Set CAL DUE
Disable Calibration
[1]
Set rear panel calibration switch to ENABLE.
Access CALIBRATION menu .
Analog to digital converter alignment. Performed only if required.
Range Zeros and Range Gains (200 mV to 1 kV Ranges).
Range Zeros, Range LF Gains and Range HF Gains (200 mV to 1 kV
Ranges).
Range Zeros and Range Gains:
Ohms: 2 Ω to 2 GΩ Ranges, then LoI Ohms.
TruΩ: 2 Ω to 20 kΩ Ranges, then LoI TruΩ.
HiVΩ: 20 MΩ to 20 GΩ Ranges.
Range Zeros and Range Gains (200 μA to 20 A Ranges).
Range Zeros and Range Gains (200 μA to 20 A Ranges).
Frequency counter cal at 1 MHz
Quit the CALIBRATION menu.
Front & rear non-volatile input offset adjustments:
DCV, Ohms, TruΩ, HiVΩ (including LoI , 2 & 4-wire).
Set the date for the next external calibration
Set rear panel calibration switch to DISABLE.
To meet user's need, just one range on one function can be calibrated.
Interconnections
The Fluke 8508A-7000K Calibration kit contains a specially designed lead set which
connects directly to the terminals of the Multimeter, the 5720A, and the 5725A for the
purpose of Multimeter calibration. It is recommended that this lead kit be used to avoid
introducing measurement errors due to interconnections and to duplicate the
http://www.elso.sk
3-11
8508A
Service Manual
riešenia na presné meranie
configuration used by Fluke for Multimeter calibration. Figure 3-1 shows the
interconnections used in detail. If alternate leads are substituted, make sure they are
metrology grade leads, and of adequate voltage and current ratings. Leads should be kept
as short as possible, constructed from low capacitance low leakage dielectric material
(PTFE) with low thermal emf terminations, and exactly duplicate the configuration and
interconnections shown.
When calibrating the 2 GΩ and 20 GΩ resistance ranges the 1 GΩ standard resistor
supplied in the Fluke 8508A-7000K Calibration kit plugs directly into the Multimeter’s
front input terminals, without any interconnecting leads. If alternate resistance standards
are used for resistance calibration, refer to the resistance-measurements section of
Chapter 3 Making Measurements for connection details.
The Fluke 8508A-7000K Calibration kit also contains two precision low-thermal emf
4-wire shorting devices for use when performing the non-volatile input offset adjustments
at the front and rear input terminals. These devices link the input terminals in the
following order: Input Lo to Input Hi to Sense Hi to Sense Lo. If these devices are not
available it is recommended that a U-shaped piece of thick bare copper wire be used to
link the terminals in the same manner.
3-12
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Red
Red
Green
Black
White
Blue
Red
Green
Red
White
Link guard
and ground
terminal
Black
Blue
CURRENT
OUTPUT
Link guard
and ground
terminal
HI
LO
White
CURRENT
OUTPUT
HI
LO
8508A REFERENCE MULTIMETER
8508A-7000K
PM
8508A - 7000K
4 W SHORT
4 10590 - A
Green
adj381f.eps
Figure 3-1. Equipment Connections Required for Calibration
http://www.elso.sk
3-13
riešenia na presné meranie
8508A
Service Manual
ADC Calibration
ADC (analog to digital converter) calibration aligns the different resolutions available
from the Multimeter’s analog to digital converter, so that there are no significant
differences in readings when changing resolutions with a constant input value. It is
recommended that ADC CAL is only performed if performance verification indicates
significant resolution differences. If required, it is recommended that ADC calibration is
performed before any other calibrations.
No external equipment or signals are required to perform ADC calibration.
Procedure
1. Ensure that no signals are present on the Multimeter’s inputs. The Multimeter may be
left connected to the calibrator as shown above provided the calibrator output is set to
STANDBY.
2. On the Multimeter, Press CAL to enter the CALIBRATION menu, and select SPCL.
3. Select Adc to initiate the calibration operation, which will take approximately 3
minutes to complete.
Calibration is complete when the Busy legend goes out.
DC Voltage Calibration
XW Warning
The Calibrator can deliver a lethal electric shock.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
Initial Setup
1. Press the DCV key, select the 200 mV range.
2. Press the CONFIG key. Select Filt.
3. In calibration mode the resolution defaults to RESL7 in the DCV function. It is
recommended that this resolution is used for calibration of all DCV ranges.
4. Reselect DCV.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
6. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
7. Connect the Calibrator to the Multimeter as shown above.
3-14
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero, then positive and negative range gains on all DCV ranges. Just one range can be
calibrated if required, but for a full calibration start with the 200 mV range and work up
to the 1kV range, as shown in Table 3-3.
Table 3-3. DC Voltage Calibration Points and Sequence
8508A Range
200 mV
2V
20 V
200 V
1000 V
Point
Zero
Voltage
0 mV
Range Gain +ve
+100 mV
Range Gain -ve
-100 mV
Zero
0V
Range Gain +ve
+1 V
Range Gain -ve
-1 V
Zero
0V
Range Gain +ve
+10 V
Range Gain -ve
-10 V
Zero
0V
Range Gain +ve
+100 V
Range Gain -ve
-100 V
Zero
0V
Range Gain +ve
+1000 V
Range Gain -ve
-1000 V
The procedure assumes the user has knowledge of the actual output value of the
calibrator at the range gain values, from a measurement or from a certificate of
calibration. The Set feature allows a user to enter the true output value of the calibration
standard where it differs from the nominal range gain point. If the calibrator output is
considered to be exactly nominal, use of the Set feature is not required, also omit steps 24 for the Range Gain Points.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied signal amplitude and polarity.
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, set zero output and Operate.
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
http://www.elso.sk
3-15
riešenia na presné meranie
8508A
Service Manual
Range Gain Points
1. On the Calibrator, select the positive Range Gain point Output value.
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator at the range gain value, then press Enter.
5. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
6. On the Calibrator, select the negative Range Gain point Output value.
7. Repeat steps 3 to 5 above to calibrate the negative Range gain point.
8. On the Calibrator, set Standby.
9. Press the DCV key to revert to the ranges menu.
AC Voltage Calibration
XW Warning
The Calibrator can deliver a lethal electric shock.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way
Initial Setup and Connections
1. Press the ACV key, select the 200 mV range..
2. Press the CONFIG key. In calibration mode in the ACV function Transfer mode
defaults to On for enhanced performance, resolution defaults to RESL6, and the
100Hz RMS filter is automatically selected. It is recommended that this resolution,
Transfer On and 100Hz Filter is used for calibration of all ACV ranges.
3. Reselect ACV.
4. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
5. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
6. Connect the Calibrator to the Multimeter as shown above.
Range Zero, LF, and HF Gain Calibration Procedure (not in Spot Frequency mode)
Using the following procedure to calibrate range zero then range LF and HF gains on all
ACV ranges at the voltages and frequencies detailed in Table 3-4. Just one range can be
calibrated if required, but for a full-calibration start with the 200 mV range and work up
to the 1kV range.
3-16
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Table 3-4. AC Voltage Calibration Points and Sequence
8508A Range
200 mV
2V
Voltage
Zero (5 % Range)
1 kHz
Range Gain LF
100 mV
1 kHz
Range Gain HF
100 mV
60 kHz
10 mV
1 kHz
Range Gain LF
1V
1 kHz
Range Gain HF
1V
60 kHz
100 mV
1 kHz
Range Gain LF
10 V
1 kHz
Range Gain HF
10 V
60 kHz
1V
1 kHz
Range Gain LF
100 V
1 kHz
Range Gain HF
100 V
60 kHz
5V
1 kHz
Range Gain LF
500 V
1 kHz
Range Gain HF
500 V
30 kHz
Zero (0.5 % Range)
200 V
1000 V
Zero (0.5 % Range)
[1]
Frequency
10 mV
Zero (0.5 % Range)
20 V
[1]
Point
Zero (0.5 % Range)
1000V range Gain calibrations may be performed at voltages above 500V. The 1000V range Gain and Zero
calibrations should be performed together, with the Zero cal performed at 1 % of the nominal value used for Gain
cal.
The procedure assumes the user has knowledge of the actual output value of the
calibrator at each point, from a measurement or from a certificate of calibration. The Set
feature allows a user to enter the true output value of the calibration standard where it
differs from the nominal point. If the calibrator output is considered to be exactly
nominal, use of the Set feature is not required, also omit steps 3-5.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero from the applied signal amplitude, and automatically recognizes the range LF and
HF gain points from the applied signal frequency.
1. On the Multimeter, select the required Range.
2. On the Calibrator select Output Voltage and Frequency, Operate
3. On the Multimeter, Press CAL to revert to CALIBRATION menu.
4. Select Set on the CALIBRATION menu.
5. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator, then press Enter.
6. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed Note that HF gain calibrations are iterative, and repeating
the HF calibration may improve the result.
7. On the Calibrator, set Output to STANDBY.
8. On the Multimeter, press ACV key to revert to the ranges menu.
http://www.elso.sk
3-17
riešenia na presné meranie
8508A
Service Manual
Resistance Calibration
When calibrating the resistance function, each of the resistance modes (Normal, LoI,
TruΩ, TruΩ LoI and HiVΩ) must be individually calibrated. The following procedure
assumes use of a multifunction calibrator and calibrates each resistance mode in turn,
range by range. If individual standard resistors are used it may be more convenient to
calibrate all the modes in turn for each resistance value to avoid connecting the same
resistance standard several times during the calibration sequence. A 1 GΩ standard
resistor provided in the 8508A-7000K calibration kit is used for ranges above 200 MΩ as
the highest resistance available from the 5720A calibrator is 100 MΩ. Refer to Table 3-5
for the resistance calibration points and sequence.
Table 3-5. Resistance Calibration Points and Sequence
8508A Range
2Ω
20 Ω
200 Ω
2 kΩ
20 kΩ
200 kΩ
Modes
Point
Normal, Normal LoI,
Zero
0Ω
TruΩ, TruΩ LoI
Range Gain
1Ω
Normal, Normal LoI,
Zero
0Ω
TruΩ, TruΩ LoI
Range Gain
Normal, Normal LoI,
Zero
TruΩ, TruΩ LoI
Range Gain
Normal, Normal LoI,
Zero
TruΩ, TruΩ LoI
Range Gain
Normal, Normal LoI,
Zero
TruΩ, TruΩ LoI
Range Gain
Normal, Normal LoI
Zero
Range Gain
2 MΩ
Normal, Normal LoI
Zero
Range Gain
20 MΩ
200 MΩ
2 GΩ
20 GΩ
Normal, Normal LoI,
HiVΩ
Zero
Normal, Normal LoI,
HiVΩ
Zero
Normal, Normal LoI,
HiVΩ
Zero
HiVΩ
Zero
Range Gain
Range Gain
Range Gain
Range Gain
[1]
3-18
Resistance
10 Ω
0Ω
100 Ω
0Ω
1 kΩ
0Ω
10 kΩ
0Ω
100 kΩ
0Ω
1 MΩ
0Ω
10 MΩ
0Ω
100 MΩ
0Ω
1 GΩ
0Ω
Optional[1]
20 GΩ range gain is calibrated automatically during 2 GΩ HiVΩ range gain cal, but may be calibrated separately
(after 2 GΩ HiVΩ range cal) at 10 GΩ if a standard is available. The 100 MΩ and 2 GΩ NormalΩ ranges must be
calibrated before 2 GΩ HiVΩ range gain point.
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Initial Setup and Connections
1. Press the Ω key and select the 200 Ω range.
2. Press the CONFIG key and select Filt and 4wΩ.
3. In calibration mode the resolution defaults to RESL7 in the resistance function. It is
recommended that this resolution is used for calibration of all resistance ranges.
4. Reselect Ω.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
6. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected). On the calibrator select EX SNS (4-wire).
7. Connect the Calibrator to the Multimeter as shown earlier in this chapter.
8. If using standard resistors in place of the calibrator refer to "Measuring Resistance"
in Chapter 3 of the Users Manual for information regarding 4-wire resistance
connections.
NormalΩ Mode Calibration
1. Press the Ω key and select the 2 Ω range.
2. Press the CONFIG key and select Filt and 4wΩ. Ensure LoI is deselected.
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero and range gain for the ranges and points detailed in Table 3-5 for the NormalΩ
mode. For the 2 GΩ range use the 1 GΩ standard resistor in place of the calibrator. Just
one range can be calibrated if required, but for a full-calibration start with the 2 Ω range
and work up to the 2 GΩ range.
Note that EX SNS (4-wire) is not available on the 5720A 100 MΩ range, and the 85087000K 1 GΩ standard resistor is used as a 2-wire device with the calibrator 2-wire
resistance zero used for the corresponding zero points. 4WΩ is deselected on the
Multimeter when calibrating the 200 MΩ and 2 GΩ range, range zero, and range gain
points.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied resistance value.
Note
It is unlikely that the resistance standard will be at exactly the nominal
value required. The Set feature allows a user to enter the true output value
of the calibration standard where it differs from nominal range gain point.
If the resistance value is exactly the nominal value required, omit steps 2-4
for the Range Gain Point.
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, select zero and Operate. Alternatively if using a standard resistor
connect the standard resistor for a 4-wire resistance zero. (For the 200 MΩ and 2 GΩ
ranges, de-select EX SNS on the calibrator and de-select 4WΩ οn the Multimeter.)
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
http://www.elso.sk
3-19
8508A
Service Manual
riešenia na presné meranie
Calibration is complete when the Busy legend goes out and the calibrated measurement is
displayed
Range Gain Point
1. On the Calibrator, select the Range Gain point resistance value. Alternatively if using
a standard resistor re-connect the standard resistor to measure its resistance. (For the
2 GΩ range the 8508-7000K 1 GΩ standard resistor is used in place of the calibrator.
For the 200 MΩ and 2 GΩ ranges, de-select EX SNS on the calibrator and de-select
4WΩ οn the Multimeter.)
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator (or the value of the resistance standard) at the range gain value, then
press Enter.
5. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
6. On the Calibrator, set STANDBY.
7. Press the Ω key to revert to the ranges menu.
LoIΩ Mode Calibration
1. Press the Ω key and select the 2 Ω range.
2. Press the CONFIG key and select Filt, LoI and 4wΩ.
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero and range gain for the ranges and points detailed in Table 3-5 for the LoI mode. For
the 2 GΩ range use the 1 GΩ standard resistor in place of the calibrator. Just one range
can be calibrated, if required, but for a full-calibration start with the 2 Ω range and work
up to the 2 GΩ range.
Note that EX SNS (4-wire) is not available on the 5720A 100 MΩ range, and the 85087000K 1 GΩ standard resistor is used as a 2-wire device with the calibrator 2-wire
resistance zero used for the corresponding zero points. 4WΩ is deselected on the
Multimeter when calibrating the 200 MΩ and 2 GΩ range, range zero, and range gain
points.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied resistance value.
Note
It is unlikely that the resistance standard will be at exactly the nominal
value required. The Set feature allows a user to enter the true output value
of the calibration standard where it differs from nominal range gain point.
If the resistance value is exactly the nominal value required, omit steps 2-4
for the Range Gain Point.
3-20
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, select zero Ω and Operate. Alternatively if using a standard
resistor connect the standard resistor for a 4-wire resistance zero. (For the 200 MΩ
and 2 GΩ ranges, de-select Ex SNS on the calibrator and de-select 4WΩ οn the
Multimeter.)
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
Range Gain Point
1. On the Calibrator, select the Range Gain point resistance value. Alternatively if using
a standard resistor re-connect the standard resistor to measure its resistance. (For the
2 GΩ range the 8508-7000K 1 GΩ standard resistor is used in place of the calibrator.
For the 200 MΩ and 2 GΩ ranges, de-select Ex SNS on the calibrator and de-select
4WΩ οn the Multimeter.)
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator (or the value of the resistance standard) at the range gain value, then
press Enter.
5. Press SAMPLE.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
6. On the Calibrator, set STANDBY.
7. Press the Ω key to revert to the ranges menu.
TruΩ Mode Calibration
1. Press the Ω Plus key and select TruΩ. From the TruΩ menu select the 2 Ω range.
2. Press the CONFIG key and select Filt and 4wΩ. Ensure LoI is deselected.
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero and range gain for the ranges and points detailed in Table 3-5 for the TruΩ mode.
Just one range can be calibrated, if required, but for a full-calibration start with the 2 Ω
range and work up to the 20 kΩ range.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied resistance value.
Note
It is unlikely that the resistance standard will be at exactly the nominal
value required. The Set feature allows a user to enter the true output value
of the calibration standard where it differs from nominal range gain point.
If the resistance value is exactly the nominal value required, omit steps 2-4
for the Range Gain Point.
http://www.elso.sk
3-21
8508A
Service Manual
riešenia na presné meranie
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, select zero Ω and Operate. Alternatively if using a standard
resistor connect the standard resistor for a 4-wire resistance zero.
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
Range Gain Point
1. On the Calibrator, select Range Gain point Output value. Alternatively if using a
standard resistor re-connect the standard resistor to measure its resistance.
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator (or the value of the resistance standard) at the range gain value, then
press Enter.
5. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
6. On the Calibrator, set STANDBY.
7. Press the Ω key to revert to the ranges menu.
TruΩ LoI Mode Calibration
1. Press the Ω Plus key and select TruΩ. From the TruΩ menu select the 2Ω range.
2. Press the CONFIG key and select Filt, LoI and 4wΩ.
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero and range gain for the ranges and points detailed in Table 3-5 for the TruΩ LoI
mode. Just one range can be calibrated if required, but for a full calibration start with the
2 Ω range and work up to the 20 kΩ range.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied resistance value.
Note
It is unlikely that the resistance standard will be at exactly the nominal
value required. The Set feature allows a user to enter the true output value
of the calibration standard where it differs from nominal range gain point.
If the resistance value is exactly the nominal value required, omit steps 2-4
for the Range Gain Point.
3-22
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, select zero Ω and Operate. Alternatively if using a standard
resistor connect the standard resistor for a 4-wire resistance zero.
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
Range Gain Point
1. On the Calibrator, select Range Gain point Output value. Alternatively if using a
standard resistor re-connect the standard resistor to measure its resistance.
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator (or the value of the resistance standard) at the range gain value, then
press Enter.
5. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
6. On the Calibrator, set STANDBY.
7. Press the Ω key to revert to the ranges menu.
HiVΩ Mode Calibration
XW Warning
The Multimeter can deliver a lethal electric shock when
operating in the High Voltage Resistance mode. Voltages up to
240V may appear on the terminals.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
1. Press the Ω Plus key and select HiVΩ. From the HiVΩ menu select the 20 MΩ range.
2. Press the CONFIG key and select Filt and 4wΩ.
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero and range gain for the ranges and points detailed in Table 3-5 for the HiVΩ mode.
Just one range can be calibrated if required, but for a full calibration start with the 20 MΩ
range and work up to the 20 GΩ range.
http://www.elso.sk
3-23
8508A
Service Manual
riešenia na presné meranie
For the 2 GΩ range use the 1 GΩ standard resistor in place of the calibrator. To avoid the
requirement for a 10 GΩ standard, the 20 GΩ range is automatically calibrated when the
2 GΩ range gain calibration is triggered. It is also necessary for the 100 MΩ and 1 GΩ
NormalΩ ranges to be calibrated prior to the 2 GΩ HiVΩ range for the result to be valid.
A 10 GΩ standard resistor may be used for calibrating the 20 GΩ range if available, but
if performed, this operation must take place after the 2 GΩ range gain point calibration to
avoid the automatic process overwriting the result.
Voltages of approximately 200V will be developed across the resistance standard at full
scale, ensure the resistance standards used are suitable for operation at these voltages.
Note that EX SNS (4-wire) is not available on the 5720A 100 MΩ range, and the 85087000K 1 GΩ standard resistor is used as a 2-wire device with the calibrator 2-wire
resistance zero used for the corresponding zero points. 4WΩ is deselected on the
Multimeter when calibrating the 200 MΩ and 2 GΩ range, range zero, and range gain
points.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied resistance value.
Note
It is unlikely that the resistance standard will be at exactly the nominal
value required. The Set feature allows a user to enter the true output value
of the calibration standard where it differs from nominal range gain point.
If the resistance value is exactly the nominal value required, omit steps 2-4
for the Range Gain Point .
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, select zero Ω and Operate. (For the 200 MΩ range and above, deselect Ex SNS on the calibrator and de-select 4WΩ οn the Multimeter.) Alternatively
if using a standard resistor connect the standard resistor for a 4-wire resistance zero.
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
Range Gain Point
1. On the Calibrator, select Range Gain point Output value. Alternatively if using a
standard resistor re-connect the standard resistor to measure its resistance. (For the
2 GΩ range the 8508-7000K 1 GΩ standard resistor is used in place of the calibrator.
For the 200 MΩ range and above, de-select Ex SNS on the calibrator and de-select
4WΩ οn the Multimeter. Calibration of the 20 GΩ range gain point takes place
automatically when calibrating 2 GΩ range, and calibration against an external
standard is optional if a suitable standard is available).
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator (or the value of the resistance standard) at the range gain value, then
press Enter.
3-24
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
5. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
6. On the Calibrator, set STANDBY.
7. Press the Ω key to revert to the ranges menu.
DC Current Calibration
XW Warning
The Calibrator can deliver a lethal electric shock.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
Initial Setup
1. Press the DCI key, select the 200 μA range.
2. Press the CONFIG key. Select Filt.
3. In calibration mode the resolution defaults to RESL7 in the DCI function. It is
recommended that this resolution is used for calibration of all DCI ranges.
4. Reselect DCI.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
6. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
7. Connect the Calibrator to the Multimeter as shown above.
Range Zero and Gain Calibration Procedure
After the initial setup and connecting up, use the following procedure to calibrate range
zero, then positive and negative range gains on all DCI ranges. Just one range can be
calibrated if required, but for a full calibration start with the 200 μA range and work up to
the 20A range, as shown in Table 3-6.
http://www.elso.sk
3-25
riešenia na presné meranie
8508A
Service Manual
Table 3-6. DC Current Calibration Points and Sequence
8508A Range
200 μA
2 mA
20 mA
200 mA
2A
20 A
Point
Zero
Current
0 μA
Range Gain +ve
+100 μA
Range Gain -ve
-100 μA
Zero
0 mA
Range Gain +ve
+1 mA
Range Gain -ve
-1 mA
Zero
0 mA
Range Gain +ve
+10 mA
Range Gain -ve
-10 mA
Zero
0 mA
Range Gain +ve
+100 mA
Range Gain -ve
-100 mA
Zero
0A
Range Gain +ve
+1 A
Range Gain -ve
-1 A
Zero
0A
Range Gain +ve
+10 A
Range Gain -ve
-10 A
The procedure assumes the user has knowledge of the actual output value of the
calibrator at the range gain values, from a measurement or from a certificate of
calibration. The Set feature allows a user to enter the true output value of the calibration
standard where it differs from the nominal range gain point. If the calibrator output is
considered to be exactly nominal, use of the Set feature is not required, also omit steps 24 for the Range Gain Points.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied signal amplitude and polarity.
Zero Point
1. On the Multimeter, select the required range.
2. On the Calibrator, set to zero output and Operate.
3. On the Multimeter, press CAL to enter the CALIBRATION menu.
4. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
3-26
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Range Gain Points
1. On the Calibrator, select the positive Range Gain point Output value.
2. On the Multimeter, Press CAL to revert to CALIBRATION menu.
3. Select Set on the CALIBRATION menu.
4. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator at the range gain value, then press Enter.
5. Press SAMPLE to initiate the calibration operation.
6. Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
7. On the Calibrator, select the negative Range Gain point Output value.
8. Repeat steps 3 to 5 above to calibrate the negative Range gain point.
9. On the Calibrator, set STANDBY.
10. Press the DCI key to revert to the ranges menu.
AC Current Calibration
XW Warning
The Calibrator can deliver a lethal electric shock.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
Initial Setup and Connections
1. Press the ACI key, and select the 200μA range.
2. Press the CONFIG key. In calibration mode in the ACI function resolution defaults to
RESL6 and the 100Hz RMS filter is automatically selected. It is recommended that
this resolution and 100Hz Filter is used for calibration of all ACI ranges.
3. Reselect ACI.
4. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
5. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
6. Connect the Calibrator to the Multimeter as shown above.
Range Zero and LF Gain Calibration Procedure
Using the following procedure to calibrate range zero then range gain on all ACI ranges
at the currents and frequencies detailed in Table 3-7. Just one range can be calibrated if
required, but for a full-calibration start with the 200 µA range and work up to the 20A
range.
http://www.elso.sk
3-27
riešenia na presné meranie
8508A
Service Manual
Table 3-7. AC Current Calibration Points and Sequence
8508A Range
200 μA
Point
20 mA
200 mA
2A
20 A
Frequency
10 μA
300 Hz
100 μA
300 Hz
Zero (0.5 % Range)
10 μA
300 Hz
Range Gain
1 mA
300 Hz
Zero (0.5 % Range)
100 μA
300 Hz
Range Gain
10 mA
300 Hz
Zero (5 % Range)
10 mA
300 Hz
Range Gain
100 mA
300 Hz
Zero (5 % Range)
100 mA
300 Hz
Range Gain
1A
300 Hz
Zero (5 % Range)
1A
300 Hz
10 A
300 Hz
Zero (5 % Range)
Range Gain
2 mA
Current
Range Gain
The procedure assumes the user has knowledge of the actual output value of the
calibrator at each point, from a measurement or from a certificate of calibration. The Set
feature allows a user to enter the true output value of the calibration standard where it
differs from the nominal point. If the calibrator output is considered to be exactly
nominal, use of the Set feature is not required, also omit steps 3-5.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied signal amplitude.
1. On the Multimeter, select the required Range.
2. On the Calibrator select Output Current and Frequency, Operate.
3. On the Multimeter, Press CAL to revert to CALIBRATION menu.
4. Select Set on the CALIBRATION menu.
5. Use the numeric keys with the SET VALUE menu to key in the true output value of
the calibrator, then press Enter.
6. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed.
7. On the Calibrator, set Output to STANDBY.
8. On the Multimeter, press ACI key to revert to the ranges menu.
Frequency Calibration
The Multimeter frequency calibration operation requires a signal at exactly 1MHz (Set is
not available on the Multimeter for frequency calibration). If the calibrator frequency
output is not exactly nominal or sufficiently close to nominal it may be phase locked to
an external reference frequency at the required output frequency applied to its rear panel
phase lock input, for example from a laboratory frequency standard or off-air reference
receiver. If used, the calibrator should be disconnected from the frequency reference and
phase locking disabled before attempting any other calibration operations with the
calibrator.
3-28
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Routine Calibration
3
Alternatively, the 1MHz frequency reference may be used directly as an input signal for
the Multimeter for frequency calibration.
Initial Setup and Connections
1. Press the ACV key, select the 2 V range.
2. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
3. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
4. Connect the Calibrator to the Multimeter as shown above.
5. If required, connect the calibrator rear panel phase lock input to a 1MHz reference
frequency and enable phase locking via the front panel menus.
Procedure
1. On the calibrator select 1V 1MHz, Operate.
2. On the Multimeter, Press CAL to enter the CALIBRATION menu, and select SPCL.
3. Select Freq to initiate the calibration operation.
Calibration is complete when the Busy legend goes out.
4. On the Calibrator, set STANDBY.
Exit From Calibration Mode and Non-Volatile Input Offset Adjustment
Use the following procedure to perform non-volatile input offset adjustment on all DCV
and resistance ranges (including LoI, 2-wire, and 4-wire) for the front and rear inputs.
Initial Setup and Connections
1. Press the CAL key and select Quit.
2. From the CAL DUE ? menu select Quit.
3. The Multimeter will exit from CAL mode, the CAL legend on the main display will
extinguish, and he right-hand display will revert to the currently selected function
menu.
4. Disconnect all calibration leads and connect a 8508-7000K precision 4-wire short
device to the front input terminals and also, if fitted, to the input terminals as shown
above.
Procedure
Omit step 4 if the Multimeter is not fitted with rear input terminals.
1. Press the DCV key
2. Press the INPUT key and select Front.
3. From the INPUT menu select Zero Func to perform zero offset adjustment on all
ranges.
4. From the INPUT menu select Rear. Repeat step 3.
5. Press the Ω key and select the 2 Ω range.
http://www.elso.sk
3-29
8508A
Service Manual
riešenia na presné meranie
6. Press the CONFIG key and select Filt, LoI and 4wΩ. Repeat steps 3 and 4.
7. Press the CONFIG key and select 2wΩ. Repeat steps 3 and 4.
8. Press the CONFIG key, select 4wΩ and de-select LoI. Repeat steps 3 and 4.
9. Press the CONFIG key and select 2wΩ. Repeat steps 3 and 4.
10. Press the ΩPLUS key and select TruΩ. From the TruΩ menu the 2Ω range.
11. Press the CONFIG key and select Filt and LoI. Repeat steps 3 and 4.
12. Press the CONFIG key and de-select LoI. Repeat steps 3 and 4.
13. Press the ΩPLUS key and select HiVΩ. From the HiVΩ menu the 20MΩ range.
14. Press the CONFIG key and select Filt and 2wΩ. Repeat steps 3 and 4.
15. Press the CONFIG key and select 4wΩ. Repeat steps 3 and 4.
16. Press the DCV key and remove the shorting devices from the input terminals.
Cal Due Date Entry and Calibration Mode Disable
On completion of all calibration operations it is recommended that the user updates the
stored CAL due date with the date for next recalibration. For consistency, this date should
be the same as the calibration due date shown on any calibration stickers the user may
also attach to the Multimeter. It is also recommended that a calibration seal or integrity
sticker is applied to prevent unauthorized access to the rear panel calibration enable
switch.
Set Cal Due Date
1. Press the CAL key and select Quit.
2. From the CAL DUE ? menu select Enter.
3. Use the keypad to key in the calibration due date. Up to eight characters may be
entered in any format. Any character available from the keypad may be used, but it is
recommended that one of the common date formats such as dd.mm.yy or mm.dd.yy
is used for ease of interpretation.
4. Press Enter to store the CAL due date.
Disable cal mode
1. Set the rear panel Calibration Enable switch to DISABLE .
2. Apply a security seal to cover the rear panel Calibration Enable switch to prevent
unauthorized access.
ACV Spot Frequency Calibration
The ACV Spot frequency mode calibration is not normally performed as part of routine
calibration. ACV Spot frequency calibration is only performed if the user intends to make
use of spot frequency mode. In spot frequency mode the accuracy of AC Voltage
measurements can be improved by calibrating the Multimeter at specific frequencies of
interest, reducing frequency response flatness errors at these points. The following
procedure provides guidance on spot frequency calibration for users wishing to make use
of Spot frequency mode.
3-30
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
To Calibrate at Spot Frequencies
Spot Calibration is available only when in AC Voltage function with Spot already
selected on the ACV CONFIG menu. Each spot (six per range) can be calibrated at a valid
input frequency to a non-nominal RMS value. In subsequent use, frequency response
flatness errors are reduced within ±10 % of the calibrated spot frequency.
Assuming that the Multimeter is in calibration mode and the setup is connected as
described above under Initial Setup and Connections for routine calibration. The
configuration defaults to Tfer and RESL6 (both required).
Proceed as follows:
1. Select ACV and select the required Range.
2. Press the CONFIG key and select Spot.
3. Press the CAL key.
The CALIBRATION menu is displayed.
4. Select Set.
The SPOT CAL menu is displayed.
5. Select the soft key for the required spot, 1 to 6 (Sp1 to Sp6).
The SPOT (x = 1 to 6) RMS menu is displayed.
6. Key in the true RMS output value of the standard, then select Enter.
The SPOT FREQUENCY menu is displayed, showing the frequency at which the
spot will be calibrated.
7. Press SAMPLE to initiate the calibration operation.
Calibration is complete when the Busy legend goes out and the calibrated
measurement is displayed. The menu display reverts to the SPOT CAL menu.
8. On the Calibrator, set STANDBY.
9. On the Multimeter, select other spots as required, repeating the process for each
selection.
10. Exit from the SPOT CAL menu by pressing any hard key.
Performance Verification
The 8508A Digital Reference Multimeter offers state of the art performance. This
procedure is intended as a guide for qualified metrology personnel who have access to a
standards laboratory with equipment available to verify the performance of an instrument
of this level of accuracy. The procedure assumes users are familiar with relevant best
measurement practice, and will take precautions to avoid introducing errors from sources
such as thermal emfs, leakages, electromagnetic interference, etc. It also assumes users
will make adequate allowance for equipment stabilization and measurement settling
times.
This routine performance verification procedure describes the test points and sequence of
operations required to check the Multimeter and assumes calibration references of
adequate traceable uncertainty are available – in this case a Fluke 5720A calibrator and
5725A amplifier used with an 8508A-7000 Calibration Kit. The procedure assumes the
user is able to calibrate and characterize the calibration standards, without describing the
process required to do so. Refer to the Routine Calibration section for more information
on the characterization process.
http://www.elso.sk
3-31
8508A
Service Manual
riešenia na presné meranie
Equipment Requirements
The equipment required for performance verification of the Multimeter is identical to the
equipment required for routine calibration listed in Table 3-1. Alternate equipment may
be used, but users should ensure it provides adequate uncertainties, and consider the
impact of those uncertainties on allowable tolerance limits.
Interconnections
The Fluke 8508A-7000K Calibration kit contains a specially designed lead set which
connects directly to the terminals of the Multimeter, the 5720A, and the 5725A for the
purpose of Multimeter calibration and performance verification. It is recommended that
this lead kit be used to avoid introducing measurement errors due to interconnections and
to duplicate the configuration used by Fluke for Multimeter calibration. A diagram
showing the interconnections used in detail appears in the Routine Calibration section. If
alternate leads are substituted users must ensure they are metrology grade leads, and of
adequate voltage and current rating. Leads should be kept as short as possible,
constructed from low capacitance low leakage dielectric material (PTFE) with low
thermal emf terminations, and exactly duplicate the configuration and interconnections
shown.
When checking the 2 GΩ and 20 GΩ resistance ranges the 1 GΩ standard resistor
supplied in the Fluke 8508A-7000K Calibration kit plugs directly into the Multimeter’s
front input terminals without any interconnecting leads. If alternate resistance standards
are used for verifying performance of the resistance function, refer to the resistance
measurements section of Chapter 3 Making Measurements for connection details.
Applicable Verification Tolerance and Conditions
The tolerances* listed in this verification procedure are derived from the Multimeter’s
365 day Tcal ±1 °C 99 % Confidence Level Absolute specifications, which include
contributions for the performance of the Multimeter itself and the uncertainty of the
calibration standards used to perform calibration adjustment of the Multimeter at the
Fluke factory. They are applicable to a verification performed within a period of 365 days
from calibration and at a temperature within ±1 °C of the temperature at which
calibration was performed (23 °C for calibrations performed by Fluke). It is
recommended that these tolerances only be used for verification of the Multimeter
following calibration by Fluke, and if the above time period and temperature conditions
are met. No allowance has been made for the uncertainty of the equipment used for
verification. If the required conditions are met but the temperature lies within ±5 °C of
factory calibration, it is recommended that the user applies the 365 day Tcal ±5 °C
Absolute specifications instead.
For other circumstances, such as following calibration by another laboratory, it is
recommended that the user derive verification tolerances* from the applicable
Multimeter’s 99 % Confidence Level Relative to Standards specifications (90 day or 365
day) combined with the calibration uncertainties applicable to the previous calibration.
(RSS summation is recommended, with calibration uncertainties also expressed at 99 %
confidence level).
The Multimeter’s temperature coefficient specifications should also be applied if the
temperature at verification is outside the range applicable to the Multimeter’s
specifications.
Refer to Chapter 1 for further information on applying specifications and combining
uncertainties.
3-32
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
* Fluke guarantees the Multimeter’s performance verification using specifications stated
to 99 % confidence level.
Preparation
1. Allow the Multimeter to warm-up under power in the specified environment for at
least 4 hours.
2. Press the CLEAR key, select Pwr Up Dflt to restore the power up default configuration
and display the DCV menu.
3. Press the Test key and select Std to initiate a selftest. Should the Multimeter fail,
contact your local authorized Service Center, ensuring that the full circumstances of
the failure are reported.
DC Voltage Checks
XW Warning
The Calibrator can deliver a lethal electric shock.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
Equipment Configuration
1. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
2. Connect the equipment as described for Routine Calibration.
3. Press the DCV key
4. Press the CONFIG key. Select Filt and RESL7.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
Procedure
Repeat the following sequence for each range, starting with the 200mV range and
working up to the 1kV range, as listed in Table 3-8. An input zero operation is performed
on each Multimeter range prior to performing the range verification measurements with
the calibrator set to zero by range locking the calibrator in the range from which the
output will be obtained.
1. Select the required Multimeter range.
2. On the calibrator set the output to zero. Select OPERATE.
3. On the Multimeter press the INPUT key, and select Zero Rng to initiate the zeroing
operation.
The Busy legend will appear, and then extinguish when the zero operation has
completed.
4. On the calibrator select the value required for verification in the positive polarity.
http://www.elso.sk
3-33
riešenia na presné meranie
8508A
Service Manual
5. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account any known error from nominal of the calibrator for this output.
6. On the calibrator select the value required for verification in the negative polarity.
7. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account any known error from nominal of the calibrator for this output.
8. Set the calibrator output to STANDBY.
Table 3-8. DC Voltage Verification Points and Sequence
8508A Range
200 mV
2V
20 V
200 V
1000 V
[1]
3-34
Voltage
0 mV
Tolerance
Perform input zero operation to calibrator range locked zero output
+100 mV
± 0.00072 mV
-100 mV
± 0.00072 mV
0V
Perform input zero operation to calibrator range locked zero output
+1 V
± 0.0000045 V
-1 V
± 0.0000045 V
0V
Perform input zero operation to calibrator range locked zero output
+1 V
± 0.000009 V
+10 V
± 0.000045 V
+19 V
± 0.000081 V
-1 V
± 0.000009 V
-10 V
± 0.000045 V
-19 V
± 0.000081 V
0V
Perform input zero operation to calibrator range locked zero output
+100 V
± 0.00065 V
-100 V
± 0.00065 V
0V
[1]
Perform input zero operation to calibrator range locked zero output
+1000 V
± 0.0066 V
-1000 V
± 0.0066 V
Based on 365 day Tcal ±1°C 99 %CL Absolute specifications. See comments in Applicable Verification Tolerance section above
regarding the impact of calibration uncertainties and use of other specifications.
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
AC Voltage Checks
XW Warning
The Calibrator can deliver a lethal electric shock.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
Equipment Configuration
1. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
2. Connect the equipment as described for Routine Calibration.
3. Press the ACV key
4. Press the CONFIG key. Select Tfer On and RESL6.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
Procedure
Repeat the following sequence for each range, starting with the 200mV range and
working up to the 1kV range, as listed in Table 3-9.
1. Select the required range on the multimeter.
2. On the Multimeter press CONFIG and select the appropriate filter for the point being
verified as listed in Table 3-9.
3. On the calibrator set the output to the voltage and frequency for the point being
verified as listed in Table 3-9. Set the output to OPERATE.
4. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account any known error from nominal of the calibrator for this output.
5. Repeat steps 2 – 4 for each point to be verified on the Multimeter’s range to be
verified.
6. Repeat steps 1 – 5 for each Multimeter range to be verified.
7. Set the calibrator output to STANDBY.
http://www.elso.sk
3-35
riešenia na presné meranie
8508A
Service Manual
Table 3-9. AC Voltage Verification Points and Sequence
8508A Range
200 mV
2V
20V
3-36
Voltage
Frequency
8508A Filter
Tolerance
1
100 mV
20 Hz
10 Hz
± 0.0195 mV
100 mV
55 Hz
40 Hz
± 0.0175 mV
100 mV
1 kHz
100 Hz
± 0.0149 mV
100 mV
3 kHz
100 Hz
± 0.0175 mV
100 mV
10 kHz
100 Hz
± 0.0175 mV
100 mV
30 kHz
100 Hz
± 0.0445 mV
100 mV
60 kHz
100 Hz
± 0.0995 mV
100 mV
100 kHz
100 Hz
± 0.0995 mV
1V
20 Hz
10 Hz
± 0.000144 V
1V
55 Hz
40 Hz
± 0.000119 V
1V
1 kHz
100 Hz
± 0.000099 V
1V
3 kHz
100 Hz
± 0.000119 V
1V
10 kHz
100 Hz
± 0.000119 V
1V
30 kHz
100 Hz
± 0.000295 V
1V
60 kHz
100 Hz
± 0.000795 V
1V
100 kHz
100 Hz
± 0.000795 V
1V
500 kHz
100 Hz
± 0.034000 V
1V
1 MHz
100 Hz
± 0.034000 V
1V
1 kHz
100 Hz
± 0.00032 V
10 V
20 Hz
10 Hz
± 0.00144 V
10 V
55 Hz
40 Hz
± 0.00099 V
10 V
1 kHz
100 Hz
± 0.00119 V
10 V
3 kHz
100 Hz
± 0.00119 V
10 V
10kHz
100 Hz
± 0.00119 V
10 V
30 kHz
100 Hz
± 0.00295 V
10 V
60 kHz
100 Hz
± 0.00795 V
10 V
100 kHz
100 Hz
± 0.00795 V
10 V
500 kHz
100 Hz
± 0.34000 V
10 V
1 MHz
100 Hz
± 0.34000 V
19 V
1 kHz
100 Hz
± 0.00167 V
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
Table 3-9. AC Voltage Verification Points and Sequence (cont)
8508A Range
200V
1000 V
[1]
8508A Filter
Tolerance [1]
Voltage
Frequency
100 V
20 Hz
10 Hz
± 0.0144 V
100 V
55 Hz
40 Hz
± 0.0119 V
100 V
1 kHz
100 Hz
± 0.0099 V
100 V
3 kHz
100 Hz
± 0.0119 V
100 V
10 kHz
100 Hz
± 0.0119 V
100 V
30 kHz
100 Hz
± 0.0295 V
100 V
60 kHz
100 Hz
± 0.0795 V
100 V
100 kHz
100 Hz
± 0.0795 V
500 V
55 Hz
40 Hz
± 0.088 V
500 V
1 kHz
100 Hz
± 0.088 V
500 V
3 kHz
100 Hz
± 0.088 V
500 V
10 kHz
100 Hz
± 0.088 V
500 V
30 kHz
100 Hz
± 0.223 V
1000 V
1 kHz
100 Hz
± 0.331 V
1000 V
30 kHz
100 Hz
± 1.476 V
Based on 365 day Tcal ±1°C 99 %CL Absolute specifications. See comments in Applicable Verification Tolerance section above
regarding the impact of calibration uncertainties and use of other specifications.
Resistance Checks
When verifying the resistance function, each of the resistance modes (NormalΩ, TruΩ,
LoIΩ and HiVΩ) must be individually checked. The following procedure assumes use of
a multifunction calibrator and verifies each resistance mode in turn, range by range. If
individual standard resistors are used it may be more convenient to check all the modes in
turn for each resistance value to avoid connecting the same resistance standard several
times during the calibration sequence. A 1 GΩ standard resistor is used for ranges above
200 MΩ as the highest resistance available from the 5720A calibrator is 100 MΩ.
Equipment Configuration
1. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
2. Connect the equipment as described for Routine Calibration.
3. Press the Ω key
4. Press the CONFIG key. Select Filt, RESL7, and 4WΩ.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
http://www.elso.sk
3-37
riešenia na presné meranie
8508A
Service Manual
Procedure
Perform the following sequence for each resistance mode and each range, as listed in
Table 3-10, starting with the 2 Ω range and working up to the 2 GΩ range for the
NormalΩ and NormalΩ LoI resistance modes. Then continue the sequence for the TruΩ
and TruΩ LoI modes, starting with the 2 Ω range and working up to the 20 kΩ range.
Finally complete the sequence for the HiVΩ mode, starting with the 20 MΩ range and
working up to the 20 GΩ range. An input zero operation is performed on each Multimeter
range prior to performing the range verification measurements with the calibrator set to
zero Ω. A separate zero operation is required on each range for each resistance mode.
Note that EX SNS (4-wire) is not available on the 5720A 100 MΩ range, and the 85087000K 1 GΩ standard resistor is used as a 2-wire device with the calibrator 2-wire
resistance zero used for the corresponding zero point. 4WΩ is deselected on the
Multimeter when checking the 200 MΩ and 2 GΩ range, range zero, and range gain
points.
XW Warning
The Multimeter can deliver a lethal electric shock when
operating in the High Voltage Resistance mode. Voltages up to
240V may appear on the terminals.
To avoid electric shock when performing the following
calibration procedures:
•
Never touch any lead or terminal unless you are absolutely
certain that no dangerous voltage is present.
•
Make sure that signal leads are in a safe condition before you
handle them in any way.
1. Press the Ω key.
2. Press the CONFIG key and select Filt, RESL7, and 4wΩ. Ensure LoI is deselected.
3. Select the required Multimeter range.
4. On the Calibrator, select zero Ω and Operate. Alternatively if using a standard
resistor connect the standard resistor for a 4-wire resistance zero. (For the 200 MΩ
range and above, de-select Ex SNS on the calibrator and de-select 4WΩ οn the
Multimeter.)
5. On the Multimeter press the INPUT key, and select Zero Rng to initiate the zeroing
operation.
The Busy legend will appear, and then extinguish when the zero operation has
completed.
6. On the Calibrator, select Range Gain point Output value. Alternatively if using a
standard resistor re-connect the standard resistor to measure its resistance.
7. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account the actual value of the calibrator resistance output for this value
or the calibrated value of the resistance standard used.
8. Repeat steps 3 – 7 for the remaining ranges of the selected resistance mode. (For the
2 GΩ and 20 GΩ ranges the 8508-7000K 1 GΩ standard resistor is used in place of
the calibrator. For the 200 MΩ range and above, de-select Ex SNS on the calibrator
and de-select 4WΩ οn the Multimeter).
9. Set the calibrator output to STANDBY.
3-38
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
10. Press the Ω key.
11. Press the CONFIG key and select Filt , RESL7, 4wΩ, and LoI.
12. Repeat steps 3 – 9 for the NormalΩ LoI ranges.
13. Press the Ω Plus key and select TruΩ.
14. Press the CONFIG key and select Filt , RESL7, and 4wΩ. Ensure LoI is deselected.
15. Repeat steps 3 – 9 for the TruΩ ranges.
16. Press the Ω Plus key and select TruΩ.
17. Press the CONFIG key and select Filt , RESL7, 4wΩ, and LoI.
18. Repeat steps 3 – 9 for the TruΩ LoI ranges.
19. Press the Ω Plus key and select HiVΩ.
20. Press the CONFIG key and select Filt , RESL7, and 4wΩ.
21. Repeat steps 3 – 9 for the HiVΩ ranges.
Table 3-10. Resistance Verification Points and Sequence
8508A Range
Resistance
Tolerance
Normal Ω and TruΩ
2Ω
20 Ω
200 Ω
2 kΩ
20 kΩ
200 kΩ
2 MΩ
20 MΩ
200 MΩ
2 GΩ
[2]
[1]
Normal Ω LoI and TruΩ LoI [2]
0Ω
Perform input zero operation to calibrator range locked zero output
1Ω
± 0.0000240 Ω
0Ω
Perform input zero operation to calibrator range locked zero output
10 Ω
± 0.000133 Ω
0Ω
Perform input zero operation to calibrator range locked zero output
100 Ω
± 0.00101 Ω
0 kΩ
Perform input zero operation to calibrator range locked zero output
1 kΩ
± 0.0000101 kΩ
0 kΩ
Perform input zero operation to calibrator range locked zero output
10 kΩ
± 0.000101 kΩ
0 kΩ
Perform input zero operation to calibrator range locked zero output
100 kΩ
± 0.00101 kΩ
0 MΩ
Perform input zero operation to calibrator range locked zero output
1 MΩ
± 0.0000117 MΩ
0 MΩ
Perform input zero operation to calibrator range locked zero output
10 MΩ
± 0.000320 MΩ
0 MΩ
Perform input zero operation to calibrator range locked zero output
100 MΩ
± 0.01950 MΩ
0 GΩ
Perform input zero operation to calibrator range locked zero output
1 GΩ
± 0.0018750 MΩ
http://www.elso.sk
± 0.0000240 Ω
± 0.000133 Ω
± 0.00113 Ω
± 0.0000113 kΩ
± 0.000113 kΩ
± 0.00107 kΩ
± 0.0000142 MΩ
± 0.000570 MΩ
± 0.18700 MΩ
± 0.0018750 MΩ
3-39
riešenia na presné meranie
8508A
Service Manual
Table 3-10. Resistance Verification Points and Sequence (cont)
8508A Range
Resistance
Tolerance
1
HiVΩ2
20 MΩ
200 MΩ
2 GΩ
20 GΩ
0 GΩ
Perform input zero operation to calibrator range locked zero output
10 MΩ
± 0.0000202 MΩ
0 GΩ
Perform input zero operation to calibrator range locked zero output
100 MΩ
± 0.0000870 MΩ
0 GΩ
Perform input zero operation to calibrator range locked zero output
1 GΩ
± 0.0003150 GΩ
0 GΩ
Perform input zero operation to calibrator range locked zero output
1 GΩ
± 0.012675 GΩ
[1]
Based on 365 day Tcal ±1 °C 99 %CL Absolute specifications. See comments in Applicable Verification Tolerance section above
regarding the impact of calibration uncertainties and use of other specifications.
[2]
Ranges require separate input zero operation in each resistance mode.
DC Current Checks
Equipment Configuration
1. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
2. Connect the equipment as described for Routine Calibration.
3. Press the DCI key
4. Press the CONFIG key. Select Filt and RESL7.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
Procedure
Repeat the following sequence for each range, starting with the 200μA range and
working up to the 20A range, as listed in Table 3-11. An input zero operation is
performed on each Multimeter range prior to performing the range verification
measurements with the calibrator set to zero by range locking the calibrator in the range
from which the output will be obtained.
1. Select the required Multimeter range.
2. On the calibrator set the output to zero. Select OPERATE.
3. On the Multimeter press the INPUT key, and select Zero Rng to initiate the zeroing
operation.
The Busy legend will appear, and then extinguish when the zero operation has
completed.
4. On the calibrator select the value required for verification in the positive polarity.
5. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account any known error from nominal of the calibrator for this output.
3-40
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
6. On the calibrator select the value required for verification in the negative polarity.
7. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account any known error from nominal of the calibrator for this output.
Table 3-11. DC Current Verification Points and Sequence
8508A Range
200 μA
2 mA
20 mA
200 mA
2A
20 A
[1]
Current
Tolerance
[1]
0 μA
Perform input zero operation to calibrator range locked zero output
+100μA
± 0.00190 μA
-100μA
± 0.00190 μA
0 mA
Perform input zero operation to calibrator range locked zero output
+1mA
± 0.0000190 mA
-1mA
± 0.0000190 mA
0 mA
Perform input zero operation to calibrator range locked zero output
+10mA
± 0.000200 mA
-10mA
± 0.000200 mA
0 mA
Perform input zero operation to calibrator range locked zero output
+100mA
± 0.00530 mA
-100mA
± 0.00530 mA
0A
Perform input zero operation to calibrator range locked zero output
+1A
± 0.0002260 A
-1A
± 0.0002260 A
0A
Perform input zero operation to calibrator range locked zero output
+10A
± 0.004950 A
-10A
± 0.004950 A
Based on 365 day Tcal ±1°C 99 %CL Absolute specifications. See comments in Applicable Verification Tolerance section above
regarding the impact of calibration uncertainties and use of other specifications.
AC Current Checks
Equipment Configuration
1. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
2. Connect the equipment as described for Routine Calibration.
3. Press the ACI key
4. Press the CONFIG key. Select RESL6 and 100Hz Filter.
5. Confirm that the Multimeter is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
http://www.elso.sk
3-41
riešenia na presné meranie
8508A
Service Manual
Procedure
Repeat the following sequence for each range, starting with the 200μA range and
working up to the 20A range, as listed in Table 3-12.
1. Select the required Multimeter range.
2. On the calibrator set the output to the current and frequency for the point being
verified as listed in Table 3-12. Set the output to OPERATE.
3. Note the Multimeter’s reading. Compare the result with the allowable tolerance,
taking into account any known error from nominal of the calibrator for this output.
4. Repeat steps 2 – 4 for each point to be verified on the Multimeter’s range to be
verified.
5. Repeat steps 1 – 5 for each Multimeter range to be verified.
6. Set the calibrator output to STANDBY.
Table 3-12. AC Current Verification Points and Sequence
8508A Range
200 μA
2 mA
20 mA
200 mA
2A
20 A
[1]
3-42
Tolerance [1]
Current
Frequency
100 μA
300 Hz
± 0.0830 μA
100 μA
1 kHz
± 0.0830 μA
100 μA
3 kHz
± 0.0830 μA
100 μA
5 kHz
± 0.0830 μA
100 μA
1 mA
10 kHz
± 0.0830 μA
300 Hz
± 0.000580 mA
1 mA
1 kHz
± 0.000580 mA
1 mA
3 kHz
± 0.000580 mA
1 mA
5 kHz
± 0.000580 mA
1 mA
10 kHz
± 0.000580 mA
10 mA
300 Hz
± 0.00580 mA
10 mA
1 kHz
± 0.00580 mA
10 mA
3 kHz
± 0.00580 mA
10 mA
5 kHz
± 0.00580 mA
10 mA
10 kHz
± 0.00580 mA
100 mA
300 Hz
± 0.0545 mA
100 mA
1 kHz
± 0.0545 mA
100 mA
3 kHz
± 0.0545 mA
100 mA
5 kHz
± 0.0545 mA
100 mA
10 kHz
± 0.0545 mA
1A
300 Hz
± 0.000945 A
1A
1 kHz
± 0.000945 A
1A
3 kHz
± 0.001055 A
1A
5 kHz
± 0.001055 A
1A
10 kHz
± 0.001055 A
10 A
300 Hz
± 0.01140 A
10 A
1 kHz
± 0.01140 A
10 A
3 kHz
± 0.02740 A
10 A
5 kHz
± 0.02740 A
10 A
10 kHz
± 0.02740 A
Based on 365 day Tcal ±1°C 99 %CL Absolute specifications. See comments in Applicable Verification Tolerance section above
regarding the impact of calibration uncertainties and use of other specifications.
http://www.elso.sk
riešenia na presné meranie
Calibration and Verification
Performance Verification
3
Frequency Checks
Equipment Configuration
1. Ensure that the calibrator output is set to STANDBY and configured for Internal
Guard (EXT GRD is deselected).
2. Connect the equipment as described for Routine Calibration.
3. Press the ACV key, select the 2V range
4. Press the CONFIG key. Select Tfer On, Filt 40Hz.
5. Confirm that the 8508A is configured for internal guard (External Guard is
deselected) by checking that the Ext Grd legend does not appear on the left-hand
display.
Procedure
1. On the 8508A press MONITOR and then CONFIG. Deselect FREQ GATE Fast.
2. Press the MONITOR key and select FREQ.
3. On the calibrator set the output to the voltage to 1V and frequency to 1MHz. Set the
output to OPERATE.
4. Note the Multimeter’s frequency reading. Check the result is within ±0.000012MHz,
taking into account any known error from nominal of the calibrator output frequency
for this point.
5. Set the calibrator output to STANDBY.
http://www.elso.sk
3-43
8508A
Service Manual
3-44
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
static awareness
A Message From
Fluke Corporation
Some semiconductors and custom IC's can be
damaged by electrostatic discharge during
handling. This notice explains how you can
minimize the chances of destroying such devices
by:
1. Knowing that there is a problem.
2. Leaning the guidelines for handling them.
3. Using the procedures, packaging, and
bench techniques that are recommended.
The following practices should be followed to minimize damage to S.S. (static sensitive) devices.
3. DISCHARGE PERSONAL STATIC BEFORE
HANDLING DEVICES. USE A HIGH RESISTANCE GROUNDING WRIST STRAP.
1. MINIMIZE HANDLING
2. KEEP PARTS IN ORIGINAL CONTAINERS
UNTIL READY FOR USE.
4. HANDLE S.S. DEVICES BY THE BODY.
http://www.elso.sk
riešenia na presné meranie
5. USE STATIC SHIELDING CONTAINERS FOR
HANDLING AND TRANSPORT.
8. WHEN REMOVING PLUG-IN ASSEMBLIES
HANDLE ONLY BY NON-CONDUCTIVE
EDGES AND NEVER TOUCH OPEN EDGE
CONNECTOR EXCEPT AT STATIC-FREE
WORK STATION. PLACING SHORTING
STRIPS ON EDGE CONNECTOR HELPS
PROTECT INSTALLED S.S. DEVICES.
6. DO NOT SLIDE S.S. DEVICES OVER
ANY SURFACE.
9. HANDLE S.S. DEVICES ONLY AT A
STATIC-FREE WORK STATION.
10. ONLY ANTI-STATIC TYPE SOLDERSUCKERS SHOULD BE USED.
11. ONLY GROUNDED-TIP SOLDERING
IRONS SHOULD BE USED.
7. AVOID PLASTIC,VINYL AND STYROFOAM®
IN WORK AREA.
PORTIONS REPRINTED
WITH PERMISSION FROM TEKTRONIX INC.
AND GERNER DYNAMICS, POMONA DIV.
® Dow Chemical
http://www.elso.sk
riešenia na presné meranie
Chapter 4
Maintenance
Title
Introduction..........................................................................................................
Access Procedures ...............................................................................................
Before You Start..............................................................................................
Cabling and Wiring Connections ....................................................................
Removing the A1 DC PCA .............................................................................
Removing the A2 AC PCA .............................................................................
Removing the A3 Ohms PCA .........................................................................
Removing the A4 Digital PCA........................................................................
Removing the A5 Bezel Assembly..................................................................
Removing the A5A1 Display PCA..................................................................
Removing the A6 Rear Input Assembly..........................................................
Fuse Replacement and Line-Voltage Selection ...................................................
Line-Power Fuse F1 and Voltage Selection ....................................................
Rear-Input Current Fuse F2 (Rear Inputs Option)...........................................
Self Test ...............................................................................................................
Self-Test Errors ...............................................................................................
Fatal Errors ......................................................................................................
Execution Errors..............................................................................................
Device Dependant Errors ................................................................................
http://www.elso.sk
Page
4-3
4-3
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
4-11
4-12
4-12
4-13
4-13
4-13
4-16
4-18
4-19
4-1
8508A
Service Manual
4-2
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
Maintenance
Introduction
4
Introduction
This chapter contains access procedures for replaceable assemblies (PCAs) and error
messages assocated with the self-test procedure. All of the access procedures describe
how to remove a PCA or assembly. In all cases, unless otherwise noted, the reassembly/replacement procedure is a logical reversal of the removal procedure.
Access Procedures
This section of the manual includes access procedures for the following assemblies:
•
•
•
•
•
•
•
A1 DC PCA
A2 AC PCA
A3 Ohms PCA
A4 Digital PCA
A5 Bezel Assembly
A5A1 Display PCA
A6 Rear Input Assembly
Before You Start
To ensure your safety and for the protection of the Multimeter follow all of the
considerations and recommendations that follow:
1. Unless you are qualified to service the the Multimeter do not remove the covers from
the unit.
2. To avoid shock hazards and for the protection of the unit, disconnect all power cords,
rear-panel cables, and front/rear test leads from the Multimeter.
3. Be aware that removing either or both of the cover(s) will void calibration of the
Multimeter.
4. Before removing the covers, place the Multimeter on an appropriate bench top or
work surface.
5. To avoid damage to the Multimeter from static electricity, use best practice anti-static
techniques after the covers are removed from the Multimeter.
6. Do not unnecessarily touch any part of the PCAs or straighten component positions
on the PCAs.
http://www.elso.sk
4-3
riešenia na presné meranie
8508A
Service Manual
Cabling and Wiring Connections
To help avoid making incorrect cable connections during reassembly, refer to the internal
wiring and cabling diagram shown in Figure 4-1.
FRONT
A5A1
SENSE
J202
HI
HI
LO
LO
GUARD
A
J201
A5A1 Display PCA
INPUT
A2
A3
A1
W6 (16)
A4
W5 (16)
RED
GRN
BLU
WHT
BRN
BLK
J801
J111
J109
J113
J110
J112
J130
(Yellow) E102
J132
(Green) E104
(Orange) E101
(Black) E106
(Brown) E105
(Red) E103
J121
PL30
J122
PL31
PL32
J120
A1 DC PCA (top)
A3 Ohms PCA
+
A2 AC PCA
J301
PL33
W2 (16)
J801
J154
J152 J153
J15
J401
W4 (26)
(16_pin)
J151
W3 (16)
A1 DC PCA
(top)
(4)
(10)
J302
J301
(3)
J201
J502 J501
(4)
T2
T1
Power Input
and
Voltage Selection
Module
A4
Digital
PCA
(4)
J202
J401
BACK
avw032f.eps
Figure 4-1. Internal Wiring and Cabling Diagram
4-4
http://www.elso.sk
riešenia na presné meranie
Maintenance
Access Procedures
4
Removing the A1 DC PCA
Use the following procedure to remove the A1 DC PCA. See Figure 4-2.
1. Position the unit on the work surface so it is bottom-side up.
2. Remove both rear feet A.
a. Remove the three hex screws from each foot.
b. If the feet are still in place, pull them from the unit.
3. Remove the bottom cover B.
a. Remove the one philips screw at rear of the bottom cover.
b. Slide the cover toward the back of the unit, and lift it off.
4. Remove the bottom shield C.
a. Remove the six philips screws from the shield.
b. Slide the shield toward front of unit, and lift it out.
5. Remove the A1 DC PCA D.
a. Disconnect the Rear Input PCA from the A1 DC PCA.
b. Disconnect the five connectors from the rear edge of the A1 DC PCA.
c. Disconnect the 10 connectors from the front edge of the A1 DC PCA.
d. Disconnect the red and black wires from the screw termininals on the PCA.
e. Remove the two philips screws from the A1 DC PCA.
f. Slide the A1 DC PCA to the side and lift it from the chassis.
2
3
4
1
avw010f.eps
Figure 4-2. Removing the A1 DC PCA
http://www.elso.sk
4-5
riešenia na presné meranie
8508A
Service Manual
Removing the A2 AC PCA
Use the following procedure to remove the A2 AC PCA. See Figure 4-3.
1. Position the unit on the work surface so it is top-side up.
2. Remove both rear feet. A
a. Remove the three hex screws from each foot.
b. If the feet are still in place, pull them from the unit.
3. Remove the top cover. B
a. Remove the one philips screw at rear of the top cover.
b. Slide the cover toward the back of the unit, and lift it off.
4. Remove the top shield. C
a. Remove the four philips screws from the shield. D
b. Slide the shield toward front of unit, and lift it out.
5. Remove the A2 AC PCA. E
a. Remove the eight philips screws holding the shield to the A2 AC PCA.
b. Lift the shield from the PCA.
c. Disconnect the one connectors from the rear edge of the A2 AC PCA.
d. Disconnect the three connectors from the front edge of the A2 AC PCA.
e. Remove the four philips screws from the PCA.
f. Using a flat-blade screwdriver, remove the four plastic standoffs from the PCA.
g. Lift the A2 AC PCA from the chassis.
2
3
5
4
1
avw011f.eps
Figure 4-3. Removing the A2 AC PCA
4-6
http://www.elso.sk
riešenia na presné meranie
Maintenance
Access Procedures
4
Removing the A3 Ohms PCA
Use the following procedure to remove the A3 Ohms PCA. See Figure 4-4.
1. Position the unit on the work surface so it is bottom-side up.
2. Remove both rear feet. A
a. Remove the three hex screws from each foot.
b. If the feet are still in place, pull them from the unit.
3. Remove the bottom cover. B
a. Remove the one philips screw at rear of the bottom cover.
b. Slide the cover toward the back of the unit, and lift it off.
4. Locate the two connectors on the A1 DC PCA with the green, red, orange, yellow
and the black, brown wires.
5. Disconnect both connectors from the A1 DC PCA. These cables are hardwired to the
A3 Ohms PCA and must be disconnected before the A3 Ohms PCA can be removed.
6. Position the unit on the work surface so it is top-side up.
7. Remove the top shield. C
a. Remove the four philips screws from the shield.
b. Slide the shield toward front of unit, and lift it out.
8. Remove the A3 Ohms PCA. D
a. Disconnect the two connectors from the rear edge of the A3 Ohms PCA.
b. Remove the one philips screws from the A3 Ohms PCA.
c. Slide the A3 Ohms PCA toward the rear of the unit (about ¼ inch).
d. Lift the A3 Ohms PCA, and free the two hardwired cables before removing it
from the unit.
2
3
4
1
avw012f.eps
Figure 4-4. Removing the A3 Ohms PCA
http://www.elso.sk
4-7
riešenia na presné meranie
8508A
Service Manual
Removing the A4 Digital PCA
Use the following procedure to remove the A4 Digital PCA. See Figure 4-5.
1. Position the unit on the work surface so it is top-side up.
2. Remove both rear feet. A
a. Remove the three hex screws from each foot.
b. If the feet are still in place, pull them from the unit.
3. Remove the top and bottom covers. BC
a. Remove one philips screw at rear of each cover.
b. Slide the covers toward the back of the unit, and lift them off.
4. Remove the Rear Panel D
a. Remove the six flat-head philips screws from the rear panel (two on either side of
the panel and two with the input/sense connector group.
b. Remove the seven pan-head philips screws distributed across the rear panel.
c. Pull the gray sheet metal portion of the rear panel away from the unit.
5. Set the unit on its side, and remove the screw holding the input/sense connector
group to the chassis. E
6. Return the unit to its original position.
7. Disconnect the five cable connectors from the A4 Digital PCA.
8. Free the A4 Digital PCA by sliding it out the rear of the chassis. F
2
6
1
4
5
3
avw013f.eps
Figure 4-5. Removing the A4 Digital PCA
4-8
http://www.elso.sk
riešenia na presné meranie
Maintenance
Access Procedures
4
Removing the A5 Bezel Assembly
Use the following procedure to remove the A5 Bezel Assembly. See Figure 4-6.
1. Position the unit on the work surface so it is bottom-side up.
2. Remove both rear feet. A
a. Remove the three hex screws from each foot.
b. If the feet are still in place, pull them from the unit.
3. Remove the bottom cover. B
a. Remove one philips screw at rear of the bottom cover.
b. Slide the cover toward the back of the unit, and lift it off.
4. Remove the bottom shield C.
a. Remove the six philips screws from the shield.
b. Slide the shield toward front of unit, and lift it out.
5. Locate the five connectors (J109 through J113) on the A1 DC PCA with the green
and white, blue, brown, red, and black wires. (When reassembling the unit make sure
you reconnect the connectors in the left to right color sequence described in this
step).
6. Disconnect all five connectors from the A1 DC PCA. These cables are hardwired to
the A5 Bezel Assembly and must be disconnected before the A5 Bezel Assembly can
be removed.
7. Remove the two hex screws from the side of each of the front handles. D
8. Thread the disconnected cables/wires through the chassis opening and pull the A5
Bezel Assembly a few inches away from the unit. E
9. Free the A5 Bezel Assembly from the unit by disconnecting the two ribbon cables
from the A5A1 Display PCA.
2
3
1
4
5
avw014f.eps
Figure 4-6. Removing the A5 Bezel Assembly
http://www.elso.sk
4-9
riešenia na presné meranie
8508A
Service Manual
Removing the A5A1 Display PCA
Use the following procedure to remove the A5A1 Display PCA. See Figure 4-7.
1. Remove the A5 Bezel Assembly (described earlier in this chapter).
2. Remove the seven small self-threading Philips screws holding the A5A1 Display
PCA to the plastic bezel (front panel). A
3. Lift the top of the A5A1 Display PCA until it clears the lip of the bezel, and then
pull the A5A1 Display PCA toward the lip of the plastic bezel. B
Before reassembling the A5 Bezel Assembly, check the position of the rubber key
pads to ensure that all of the buttons are correctly seated in their holes. C
3
1
2
avw015f.eps
Figure 4-7. Removing the A5A1 Display PCA
4-10
http://www.elso.sk
riešenia na presné meranie
Maintenance
Access Procedures
4
Removing the A6 Rear Input Assembly
Use the following procedure to remove the A6 Rear Input Assembly. See Figure 4-8.
1. Position the unit on the work surface so it is bottom-side up.
2. Remove both rear feet. A
a. Remove the three hex screws from each foot.
b. If the feet are still in place, pull them from the unit.
3. Remove the top and bottom covers. BC
a. Remove the one philips screw at the rear of each of the covers.
b. Slide the covers toward the back of the unit, and lift them off.
4. Remove the Rear Panel. D
a. Remove the six flat-head philips screws from the rear panel (two on either side of
the panel and two with the input/sense connector group.
b. Remove the seven pan-head philips screws distributed across the rear panel.
c. Pull the gray sheet metal portion of the rear panel away from the unit.
5. Remove the bottom shield E.
a. Remove the six philips screws from the shield.
b. Slide the shield toward front of unit, and lift it out.
6. Locate, and remove the screw holding the input/sense connector group to the
chassis. F
7. Cut the tie holding the input/sense connector cable to the chassis.
8. Using a pair of long-nose pliers, release (depress) the latch on each of the three
standoff clips holding the A6A1 Rear Input PCA to the A1 DC PCA.
9. With all three latches released on the standoffs, gently unplug the A6A1 Rear Input
PCA from the A1 DC PCA by lifting it straight up and away from its connectors on
the A1 DC PCA. G
2
7
5
6
1
3
4
avw016f.eps
Figure 4-8. Removing the A6 Rear Input Assembly
http://www.elso.sk
4-11
riešenia na presné meranie
8508A
Service Manual
Fuse Replacement and Line-Voltage Selection
WCaution
To avoid fire hazard, use only the fuse arrangements that
appear in the fuse specification Tables 4-1 and 4-2 below.
Additionally, the supply network must be fused at a maximum
of 16 A, and if the power cable plug is internally fused, a 5 A
fuse must be fitted in the power cable plug.
To avoid shock hazards, disconnect all line-power and input
terminal connections before attempting to access the fuse(s).
Line-Power Fuse F1 and Voltage Selection
The power-input and voltage-selection module on the rear of the Multimeter houses the
line-power fuse F1. See Figure 4-9. A fuse tray to the right of the module serves as a fuse
holder and a line-voltage-selection device. A small window on the fuse tray shows the
currently selected line voltage, 115 or 230. The fuse rating is a function of the selected
line voltage as shown in Table 4-1.
Use the following procedure to change the fuse or change the line power selection:
1. Remove the fuse tray by placeing a small screwdriver blade under the tab on the fuse
tray and pulling the tray from the module.
2. To change the voltage selection, rotate and position the fuse holder in the tray so the
desired line voltage shows in the fuse-tray window.
3. As necessary, remove and replace the fuse with one that corresponds to the selected
line voltage. See Table 4-1.
4. Slide the fuse tray back into the power-input and voltage-selection module, and
secure it by firmly pressing it into place.
adj019f.eps
Figure 4-9. Rear Panel – Power Input Fuse and line Power Locations
Table 4-1. Power Input Fuse 1
Power Input
Fuse F1
115 VAC
230 VAC
4-12
Fuse Action
TH
Time delay HBC
TH
Time delay HBC
Fuse Rating
IEC 127 (UL/CSA)
Fluke
Part No.
Manufacturer
& Type No.
1.25 A (2 A) @ 250V
920204
Schurter
001.2505
630 mA (1 A) @ 250V
920203
Schurter
001.2502
http://www.elso.sk
riešenia na presné meranie
Maintenance
Self Test
4
Rear-Input Current Fuse F2 (Rear Inputs Option)
The rear input option includes a fuse (F2) to limit the current at the rear-input A terminal
to 2A. The fuse is located at the rear of the Multimeter just to the left of the current input
terminal (A). A half-twist of the fuse cap releases the fuse for inspection or replacement.
Use the fuse specified in Table 4-2 when replacement is necessary.
Table 4-2. Current Function Rear Input Fuse 2
Fuse Action
Fuse Rating
IEC 127 (UL / CSA)
Fluke Part No.
Manufacturer
& Type No.
1.6 A (2 A)
920071
Beswick S501
FH
Fast acting HBC
Self Test
This section of the manual contains a collection of the error codes which might be
generated either on the display of the Multimeter or by way of the IEEE-488 system bus.
Error codes described in this section are shown in tabular form with both the error codes
and the descriptions of the most likely faults, causes, or conditions. Typically, the error
codes contain two parts, a four digit address code and a two digit id code. However, some
error codes consist only of the four digit address. The combination for any given code is
identified by the presence or absence of the id column in the error code table.
The error codes are classified as Self-Test Errors, Fatal Errors, Execution Errors, and
Device Dependant Errors. All error conditions other than Fatal Errors are recoverable.
For help in determining what to do in the event of a self-test error, make a note of the full
error message and contact your nearest Fluke Service Center.
Self-Test Errors
When a Self-Test is run and successfully completed no error messages result and the
Multimeter is considered operational. If a self-test error does occur, an error message
beginning with self test failed shows on the display. A function indicator and a
test id number follow to complete the message. See Table 4-3 for descriptions of the selftest errors that might occur.
Table 4-3. Self-Test Errors
DC VOLTS
Test No 10
Err 2101
P001
Main Ref Check
Test No 11
Err 2101
P002
6.2V Ref Check
Test No 20
Err 2201
P003
100mV Range Zero Check
Test No 21
Err 2211
P004
1V Range Zero Check
Test No 22
Err 2221
P005
10V Range Zero Check
Test No 23
Err 2231
P006
100V Range Zero Check
Test No 24
Err 2241
P007
100mV Range Positive Gain Check
Test No 25
Err 2251
P008
100mV Range Negative Gain Check
Test No 26
Err 2261
P009
1V Range Positive Gain Check
Test No 27
Err 2271
P010
1V Range Negative Gain Check
http://www.elso.sk
4-13
riešenia na presné meranie
8508A
Service Manual
Test No 28
Err 2281
P011
10V Range Positive Gain Check
Test No 29
Err 2291
P012
10V Range Negative Gain Check
Test No 30
Err 2301
P013
100V Range Positive Gain Check
Test No 31
Err 2311
P014
100V Range Negative Gain Check
DC CURRENT
Test No 40
Err 2401
P032
100ųA DC Range: Zero Input Check
Test No 41
Err 2411
P033
100ųA DC Range: 100ųA Input Gain Check
Test No 42
Err 2421
P034
1mA DC Range: Zero Input Check
Test No 43
Err 2431
P035
1mA DC Range: 1mA Input Gain Check
Test No 44
Err 2441
P036
10mA DC Range: Zero Input Check
Test No 45
Err 2451
P037
10mA DC Range: 10mA Input Gain Check
Test No 46
Err 2461
P038
100mA DC Range: Zero Input Check
Test No 47
Err 2471
P039
100mA DC Range: 100mA Input Gain Check
Test No 48
Err 2481
P040
1A DC Range: Zero Input Check
Test No 49
Err 2491
P041
1A DC Range: 100mA Input Gain Check
AC CURRENT
Test No 50
Err 2501
P042
1mA AC Range: Zero Input Check
Test No 51
Err 2511
P043
1mA AC Range: 1mA Input Gain Check
RESISTANCE
4-14
Test No 60
Err 2601
P044
Follower Offset Check
Test No 61
Err 2611
P045
Follower 100mA Output Check
Test No 62
Err 2621
P046
Follower 10mA Output Check
Test No 63
Err 2631
P047
Follower 1mA Output Check
Test No 64
Err 2641
P048
3.0V Clamp Check
Test No 65
Err 2651
P049
6.7V Clamp Check
Test No 66
Err 2661
P050
27V Clamp Check
Test No 67
Err 2671
P051
Current Sink Clamp Check
Test No 68
Err 2681
P052
10ųA Current Sink and Follower 10V Output Check
Test No 69
Err 2691
P053
1ųA Current Sink Check
Test No 70
Err 2701
P054
100nA Current Sink Check
Test No 71
Err 2711
P055
10nA Current Sink Check
Test No 72
Err 2721
P056
HV Ohms Follower Offset Check
Test No 73
Err 2731
P057
HV Ohms Follower Output Current Check
Test No 74
Err 2741
P058
HV Ohms Output Voltage and 240V Clamp Check
http://www.elso.sk
riešenia na presné meranie
Maintenance
Self Test
4
AC VOLTS
Test No 80
Err 2801
P015
100mV AC Range: Zero Input Check
Test No 81
Err 2811
P016
100mV AC Range: +179mV DC Input Checks at
PreAmp Output
Test No 82
Err 2821
P017
100mV AC Range: -179mV DC Input Checks at
PreAmp Output
Test No 83
Err 2831
P018
1V AC Range: Zero Input Check
2832 raw
Test No 84
Err 2841
P019
1V AC Range: +993mV DC Input Checks at
PreAmp Output
Test No 85
Err 2851
P020
1V AC Range: -993mV DC Input Checks at PreAmp
Output
Test No 86
Err 2861
P021
1V AC Range: +993mV DC Input Checks at RMS
Converter Output
Test No 87
Err 2871
P022
1V AC Range: -993mV DC Input Checks at RMS
Converter Output
Test No 88
Err 2881
P023
10V AC Range: Zero Input Check
2882 raw
Test No 89
Err 2891
P024
10V AC Range: +9.78V DC Input Checks at
PreAmp Output
Test No 90
Err 2901
P025
10V AC Range: -9.78V DC Input Checks at PreAmp
Output
Test No 91
Err 2911
P026
100V AC Range: Zero Input Check
2912 raw
Test No 92
Err 2921
P027
100V AC Range: +9.78V DC Input Checks at
PreAmp Output
Test No 93
Err 2931
P028
100V AC Range: -9.78V DC Input Checks at
PreAmp Output
Test No 94
Err 2941
P029
1000V AC Range: Zero Input Check
2942 raw
Test No 95
Err 2951
P030
1000V AC Range: +9.78V DC Input Checks at
PreAmp Output
Test No 96
Err 2961
P031
1000V AC Range: -9.78V DC Input Checks at
PreAmp Output
http://www.elso.sk
4-15
riešenia na presné meranie
8508A
Service Manual
Fatal Errors
Fatal errors are reported only via the front panel display. These messages are all coded as
9000 series faults. Each of the fatal errors that might occur are identified in the following
paragraphs.
When a fatal error occurs the processor halts the operation of the multimeter. Cycling the
power off and on may clear the message. Howerver, fatal errors are generally caused by
hardware or software faults which require repair by at a Fluke Service Center.
9000 System Kernel Fault
Addr
id
This error is generated for system queue errors, stack overflows etc.
See Table 4-4 for descriptions of 9000 system kernel fault errors.
Table 4-4. 9000 System Kernel Fault Errors
id
Fault
00
user stack overwritten (addr = user stack pointer address)
01
activity at head of queue not current (addr = address of queue)
02
current activity not at head of queue (addr = address of queue)
9001 Run Time System Error
This error is detected and generated by the Pascal run time system support e.g. variable
out of range.
9002 Unexpected Exception
Addr
id
See Table 4-5 for descriptions of unexpected exception errors.
Table 4-5. Unexpected Exception Errors
id
Exception
02
bus error (usually due to addressing non-existant memory or IO)
03
address error (due to attempting a word access to an odd address)
04
illegal instruction
05
zero divide
08
privilege violation
09
trace (trace facility is not used)
10
unimplemented instructions
11
unimplemented instructions
24
spurious interrupt (most likely cause is noise)
9003 PROM Sumcheck Failure
9004 RAM Check Failure
4-16
http://www.elso.sk
riešenia na presné meranie
9005 Serial Interface Fault
Maintenance
Self Test
4
Addr id
When this fatal error occurs the system will continuously try to repeat whatever it was
doing - the user interface will be inoperative.
See Tabe 4-6 for descriptions of the serial interface errors.
Table 4-6. Serial Interface Errors
id
Fault
01
Phase Error
The phase counter is either out of range for the
current sequence or an interrupt from the serial
interface or delay timer occurred the other was
expected. Probably due to corruption of the phase
counter. This could be either a software or a
hardware fault.
02
NOT Transfer Complete
a) Tx_complete status was false when "interrupt on
Tx complete" received.
b) Tx_complete did not become true within timeout
period when "on RTx" received.
Both caused by fault in interface hardware, probably
digital ULA fault.
03
True Complement Error
True_compl_error was true after a read transfer.
Tested during read sequence on all transfers Can
be because serial data coming from the analog
subsystem to the digital ULA is corrupt. Could also
be a serial clock or enable problem.
04
In Guard Error
Indicates in_guard circuit latches corrupted, and
new update required. Reported as fail after 20
consecutive errors. (This signal may be polled
during updates, otherwise it causes an interrupt.)
05
State Change Timeout
Interface state change between "read", "wait" and
"write" states did not occur within timeout period.
Interface hardware fault - suggests ULA (or
associated signals) problem.
06
A-D timeout
A-D did not produce RTx within hardware timeout
period after CI. A-D or hardware fault. Suggests AD not being initiated or RTx not getting back to
digital ULA. Could be an analog problem if the A-D
locks up.
07
No RTx after abort
Latched RTx did not appear after abort sent. A-D or
CI hardware fault. Suggests A-D not being initiated
or RTx not getting back to digital ULA Could be an
analog problem if the A-D locks up.
08
Switching counter
inoperative
Switching counter in-operative when tested at
power-on. suggests ULA (or associated signals)
problem.
http://www.elso.sk
4-17
riešenia na presné meranie
8508A
Service Manual
9006 - Serial Loop Mismatch
xxxxxxxx
id
xxxxxxxx is the actual data received in binary format.
See Table 4-7 for descriptions of the serial loop mismatch errors.
Table 4-7. Serial Loop Mismatch Errors
id
Fault
00
U901_C pattern mismatch – should be 00000001 (00000000 if rear fitted)
01
U901_B pattern mismatch – should be 00010000
02
U901_A pattern mismatch – should be 10100100
03
U902_C pattern mismatch – should be 00000000
04
U902_B pattern mismatch – should be 00000000
05
U902_A pattern mismatch – should be 00000000
06
U903_C pattern mismatch – should be 00010101
07
U903_B pattern mismatch – should be 01111111
08
U903_A pattern mismatch – should be 11111011
9007 Unknown Engine Instruction
Addr id
id indicates the code that the engine was attempting to interpret as an instruction.
Execution Errors
An Execution Error is generated if a received command cannot be executed because it is
incompatible with the current device state, or because it attempts to command parameters
which are out-of-limits.
In remote operation, the EXE bit (4) is set true in the Standard-defined Event Status Byte,
and the error code number is appended to the Execution Error queue.
The error is associated with status reporting, and the queue entries can be read
destructively as LIFO by the Common query command EXQ?. There is no queue when
execution errors occur during manual operation; instead, the description of the error is
sent directly on the Menu display.
See Table 4-8 for descriptions of the execution errors.
4-18
http://www.elso.sk
riešenia na presné meranie
Maintenance
Self Test
4
Table 4-8. Execution Errors
1000-
EXE queue empty when recalled
1024-
Illegal Range/Input Combination
1001-
Option not installed
1025-
Auto not available in Tru ratio
1002-
Calibration disabled
1026-
Probe identity unrecognized
1005-
Input Zero not allowed in Scan
1027-
Input Zero not allowed in PRT
1007-
Data entry error
1028-
Only allowed in Voltage function
1008-
Must be in AC Function
1029-
Scan modes not allowed in PRT
1010-
Divide-by-zero not allowed
1030-
Scan modes not allowed in ACI/DCI
1012-
No more errors in list
1031-
4wV not available via rear input
1013-
Data out of limit
1032-
Input Zero not allowed in Cal
1014-
Illegal Range/Function combination 1033-
1015-
Command allowed only in Remote
1034-
PRT Ceof Limit @ a+, b+, c+ a-, b-, c-
1016-
Not in Special Calibration
1035-
Cannot edit the default PRT
1021-
Test not allowed when Cal enabled 1036-
Calibration not allowed in PRT
Block or Rolling average required
Device Dependant Errors
Device-dependent errors are associated mainly with test and calibration operations. A
Device-Dependent Error is generated if the device detects an internal operating fault
(e.g., during self-test). The DDE bit (3) is set true in the Standard-defined Event Status
Byte, and the error code number is appended to the Device-Dependent Error queue.
In remote mode operations, the error is associated with status reporting, and the queue
entries can be read destructively as LIFO by the Common query command DDQ?.
In local mode operations, the DDE status is checked at the end of the operation (e.g., Cal,
Zero, Test). If true, an error has occurred, and the content of the last entry in the queue is
displayed on the front panel.
If both bus and front panel users attempt to read the queue concurrently, the error data is
read out destructively on a first-come, first-served basis. Thus one of the users cannot
read the data on one interface as it has already been destroyed by reading on the other.
This difficulty should be solved by suitable application programming to avoid the
possibility of a double readout. Ideally the IEEE 488 interface should set the instrument
into REMS or RWLS to prevent confusion. The bus can ignore the queue, but the front
panel user will have to read it to continue.
There are three categories of Device Dependant Errors: Correction Errors, Corruption
Errors, and Miscellaneous Errors. The errors that may occur in each category are
described in the Table 4-9.
http://www.elso.sk
4-19
riešenia na presné meranie
8508A
Service Manual
Table 4-9. Device Dependent Errors
Correction Errors
2000-
Error During Zero Cal
The input signal was outside : Zero +/- 1 % of Full
Range
2001-
Error During Gain+ Cal
The input signal was outside : +full range +/- 10 %
of full range
2002-
Error During Gain- Cal
The input signal was outside : -full range +/- 10 %
of full range
2003-
Error During HF trim Cal
2004-
Error During Input Zero
The input signal was outside : Zero +/- 1 % of full
range
2005-
Error During LoI Zero Cal
The input signal was outside : Zero +/- 1 % of full
range
2006-
Error During LoI Gain Cal
The input signal was outside : +full range +/- 10 %
of full range
2008-
Error During A to D Cal
error numbers between 2030 and 2089 (see
section 2)
2010-
Error During Frequency Cal
2012-
Error During DCcp Cal
2025-
Error During HiV Lin Read
2026-
Error During HiV Lin Calc
2027-
Error During 2wr Ohms Calc
Corruptions
2014-
Serial Number Corrupt
2015-
Cal Due Date Corrupt
2017-
Bus Address Corrupt
2018-
Line Frequency Corrupt
2020-
Invalid Corrections (ram)
2021-
Calibration Corrupt
2022-
NV RAM Write Failure
Combined corrections – checksum error
Micellaneous
4-20
2109-
Bad Data from Analog Sys
2022-
NV Ram write failure
2023-
Engine – Load factor err
2024-
Engine – Store factor err
http://www.elso.sk
riešenia na presné meranie
Chapter 5
List of Replaceable Parts
Title
Page
Introduction..........................................................................................................
How to Obtain Parts.............................................................................................
How to Contact Fluke ..........................................................................................
Parts Lists.............................................................................................................
http://www.elso.sk
5-3
5-3
5-3
5-4
5-1
8508A
Service Manual
5-2
riešenia na presné meranie
http://www.elso.sk
riešenia na presné meranie
List of Replaceable Parts
Introduction
5
Introduction
This chapter contains an illustrated list of replaceable parts for the 8508A Reference
Multimeter to the board level only. Parts are listed by assembly; alphabetized by
reference designator. Each assembly is accompanied by an illustration showing the
location of each part and its reference designator. The parts lists give the following
information:
•
•
•
•
•
•
Reference designator
An indication if the part is subject to damage by static discharge
Description
Fluke stock number
Total quantity
Any special notes (i.e., factory-selected part)
W Caution
A * symbol indicates a device that may be damaged by static
discharge.
How to Obtain Parts
Electrical components may be ordered directly from the manufacturer by using the
manufacturers part number, or from the Fluke Corporation and its authorized
representatives by using the part number under the heading FLUKE STOCK NO. To
order components directly from Fluke Corporation, call (toll-free) 800-526-4731. Parts
price information is available from the Fluke Corporation or its representatives.
To ensure prompt delivery of the correct part, include the following information when
you place an order:
•
•
•
•
•
•
Fluke stock number
Description (as given under the Description heading)
Quantity
Reference designator
Part number and revision level of the pca containing the part.
Instrument model and serial number
How to Contact Fluke
To contact Fluke, call one of the following telephone numbers:
USA: 1-888-99-FLUKE (1-888-993-5853)
Canada: 1-800-36-FLUKE (1-800-363-5853)
Europe: +31 402-675-200
Japan: +81-3-3434-0181
Singapore: +65-738-5655
Anywhere in the world: +1-425-446-5500
Or, visit Fluke's Web site at www.fluke.com.
r Note
This instrument may contain a Nickel-Cadmium battery. Do not mix with
the solid waste stream. Spent batteries should be disposed of by a qualified
recycler or hazardous materials handler. Contact your authorized Fluke
service center for recycling information.
http://www.elso.sk
5-3
riešenia na presné meranie
8508A
Service Manual
Parts Lists
The following tables list the replaceable parts for the 8508A Reference Multimeter. Parts
are listed by assembly; alphabetized by reference designator. Each assembly is
accompanied by an illustration showing the location of each part and its reference
designator. The parts lists give the following information:
•
•
•
•
•
•
Reference designator
An indication if the part is subject to damage by static discharge
Description
Fluke stock number
Total quantity
Any special notes (i.e., factory-selected part)
W Caution
A * symbol indicates a device that may be damaged by static
discharge.
Table 5-1. 8508A Final Assembly
Reference
Description
Designator
5-4
Fluke
Tot
Part No
Qty
MP1
MP2
MP3
MP4
MP5
MP6
MP7
MP8
MP9
MP10
H1
H2
H3
Top Cover
Bottom Cover
Cover, Stripe Side
Bumper, Foot, Self Adhesive
Foot, Rear
Bottom, Foot, Moulded
Bail, Tilt Stand
Label Calibration Sticker
Label, Barcode, ModelL/Serial Number
Label, Modification Record
Washer, M4 Crinkle SS GKN
Screw, 8-32 X 3/8 SH SKTHD Black
Screw, M3 X 8 Pozipan
1988598
1988604
2398145
2398373
1628388
868786
1988619
2398123
2398138
2398114
2398274
295105
2398200
1
1
2
4
2
4
2
3
1
1
6
6
2
WF1
WF1
WF1
Fuse 630 mA 250V 20mm (TH)
Fuse 1.6A 250V 20mm (F)
Fuse 1.25A 250V 20mm (TH)
1582145
1582072
1582150
1
1
1
Mains Lead (Power Cord)
Mains Lead IEC TO CEE7/7
Mains Lead IEC UK 5A 2m
Mains Lead IEC AUS/NZ 10A 2.5m
Mains Lead IEC USA/JAPAN
Mains Lead IEC SWISS 10A 2.5m
Mains Lead IEC INDIA 10A 2.5m
SPRT 25R5 -200 TO 660 DEG C
PRT 100R -200 TO 660 DEG C
Users Manual, 8508A
Service Manual, 8508A (sold separately)
Manual Set, CD, PDF files (includes Service Manual)
769422
769455
658641
284174
769448
782771
1656430
1654000
1673798
2150128
2150143
http://www.elso.sk
Notes
1
Not shown
1
Not shown
Not shown
Not shown
1
riešenia na presné meranie
List of Replaceable Parts
Parts Lists
5
MP1
MP4
MP3
4
2
6
H1
6
MP2
H2
2
MP5
2
H3
4
MP6
2
MP7
MP8 3
MP9
MP10
avw025.eps
Figure 5-1. 8508A Final Assembly
http://www.elso.sk
5-5
8508A
Service Manual
riešenia na presné meranie
Table 5-2. 8508A Chassis Assembly
Reference
Description
Designator
A1
A2
A3
A4
A5
A6
A401
H1
H2
H3
H4
H5
H6
H7
H8
H9
H10
H11
H12
H13
H14
MP1
MP3
MP2
T1
T2
W1
W2
W3
W4
W5, W6
W7
DC PCA
AC PCA
Ohms PCA
Digital PCA
Bezel Assembly
Rear Input Assembly (optional)
Reference Module POS Assembly
Screw 8-32 X 3/8 SH SKTHD BLK
Screw M3 X 8 Pozipan
Binding Post Brass NiPL
Binding Head Brass NiPL
Clip Cable Flat Ribbon
Washer M3 INT-SHAKP SZP
Nut Full M3 SZP
Washer M6 INT-SHAKP SZP
Nut Full 1/4-28 UNF BNP
Nut Nylock M4 SZP
Washer M4 Plain SZP
Screw M3 X 6 Pozicsk
Standoff M3 X 16 M/F Nylon
Screw M3 X 8 Pozicsk
PCB Card Guide
Bush Insulating 8.8 ID Black
Hole Plug 5/8" Black
Low Voltage Transformer Assembly
Mains Transformer Assembly
Cable Sig I/P Assembly
Cable Ribbon Assembly 16W
Cable Ribbon DC-DIG Assembly
Cable Ribbon DC-OHM Assembly
Cable Ribbon DIG-DS Assembly
Wire 7/.2 PTFE 1 kV Green
Lead Kit PTFE
Lead Kit Standard
1. These are removed when the Rear Input Assembly is installed.
5-6
Fluke
Tot Qty
Notes
Part No
http://www.elso.sk
1988709
1988727
1988748
1988730
1605337
2398049
2398024
295105
2398200
102707
102889
2398320
2398239
2398288
2398263
2398301
2398295
2398242
2398189
2398221
2398192
2398312
2398347
2398358
2398036
2398060
2398008
2398013
2398072
2398085
2398097
2398150
1886203
2398911
1
1
1
1
1
1
1
4
19
1
1
4
2
2
1
1
4
4
22
4
6
2
1
7
1
1
1
1
1
1
2
1
1
*
*
*
*
*
1
riešenia na presné meranie
A2
List of Replaceable Parts
Parts Lists
8
5
H12
H2
6
MP3
H13
4
W2
AC PCA
W4
A4
Ohms PCA
Top View
2
H5
A1
MP4
H12
10
10
STICK OVER
SMALL HOLES
Bottom view
DC PCA
avw026f.eps
Figure 5-2. 8508A Chassis Assembly
http://www.elso.sk
5-7
riešenia na presné meranie
8508A
Service Manual
A1
T2
H2
2
T1
A5
DC PCA
A401
Bottom view
A401
4
H1
FORM RIBBON CABLES
AS SHOWN AND CONNECT
TO CONNECTORS ON REAR
OF DISPLAY BOARD.
W6
W5
WHITE & GREEN
BLUE
BROWN
BLACK
RED
W1
avw027f.eps
Figure 5-2. 8508A Chassis Assembly (cont)
5-8
http://www.elso.sk
riešenia na presné meranie
H7
List of Replaceable Parts
Parts Lists
5
H6
T2
H8
H9
H14
2 H10
H11
H3
H4
2
H6
H7
T2
W7
H10
2
H11
2
T1
H5
2
MP1
2
A4
W3
Digital PCA
7
MP2
NOT REQUIRED IF
REAR INPUT FITTED
7
H2
avw028.eps
Figure 5-2. 8508A Chassis Assembly (cont)
http://www.elso.sk
5-9
8508A
Service Manual
riešenia na presné meranie
Table 5-3. A5 Bezel (front panel) Assembly
Reference
Designator
A1
C1, C2
H1
H2
H3
H4
H5
H6
H7
J1, J2, J3
J4, J5
J6
L1
MP2
MP3
MP5
MP4
W1
5-10
Description
Display PCB Assembly
Capicator, ceramic, 470 pF 10% 2 kV
Screws, 8/32 x 3/8
Screw, K25 x 8, POZIPAN SZP, ST
Washer M3, Int-SHAKP SZP
Washer M4, Int-SHAKP SZP
Washer, Terminal
Nut, Full, M3, SZP
Nut Terminal 8-32 UNC
Terminal, Low Thermal, Red
Terminal, Low Thermal, Black
Terminal, Low Thermal, Blue
Ferrite Core, 8680 nH
Front Handle
Display Lens
Keypad Set
Front Panel Decal
Cable Assembly, Front Input
http://www.elso.sk
Fluke
Part No
1988711
2397993
295105
2398217
2398239
2398256
859939
2398288
850334
886382
886379
886366
2398386
1605343
1607661
1605272
1607677
2398051
Tot Qty
1
2
4
7
1
6
1
1
12
3
2
1
1
2
1
1
1
1
Notes
riešenia na presné meranie
List of Replaceable Parts
Parts Lists
5
MP1
MP5
H2 7
A1
2
MP2
L1
4
H1
2
MP2
RED WIRE
BLACK WIRES - FIT THIN
WIRE UNDER THICK WIRE
PINK WIRE
BROWN WIRE
BLUE WIRE
WHITE WIRE
H3
H6
ALL WIRES EXCEPT GREEN
LOOP ONCE THROUGH FERRITE
C1
C2
GREEN WIRE
NOTE !! POSITION CAPACITOR
AWAY FROM OTHER TERMINALS.
H7
H4
12
6
H5
6
RED
BLK
RED
BLK
BLU
RED
J1
J2
J5
J3
J4
J6
MP4
MP3
W1
avw029f.eps
Figure 5-3. A5 Bezel (front panel) Assembly
http://www.elso.sk
5-11
8508A
Service Manual
riešenia na presné meranie
Table 5-4. A6 Rear Input Assembly (optional)
Reference
Description
Designator
A1
C1, C2
WF1
FH
H1
H2
H3
H4
H5
H6
H7
H8
H9
H10
H11
H12
H13
H14
J2, J4
J1, J3, J5
J6
L1
W1
5-12
Fluke
Tot Qty
Part No
Rear Input PCA
Capicator CD 470 pF 10% 2 kV
Fuse 1.6 A 250 V 20 mm
Fuse Holder 20 mm Panel Mount
Tie, Cable 3.6 x 142 mm
Washer M4 Int-Shakp SZP
Nut 8-32 UNC Terminal
Washer Terminal
Washer Terminal Large
Washer M3 Int-Shakp SZP
Nut Full M3 SZP
Screw M3 x 6 POSICSK SZP
Tie Cable 2.5 x 115 mm
Tie Holder
Screw M3 x 8 POZIPAN SEMS
Circuit Board, Support
Terminal Insulator
Terminal Base
Terminal, Low Thermal, Black
Terminal, Low Thermal, Red
Terminal, Low Thermal, Blue
Ferrite 26 x 14 x 11 8680 nF
Cable Assembly Rear Input (8 wires w/ terminals)
http://www.elso.sk
2399180
2397993
1582072
2398399
2398161
2398256
850334
859939
613606
2398239
2398288
2398189
2398177
2398335
2398200
2398364
894183
885459
886379
886382
886366
2398386
2398106
1
2
1
1
1
6
12
6
6
1
1
2
3
1
1
3
6
6
2
3
1
1
1
Notes
riešenia na presné meranie
List of Replaceable Parts
Parts Lists
5
H12
2
H8
H11
H9
H10
L1
8 wires with terminals
H9
L1
2
GREEN
WHITE
BLACK ORANGE
BLUE
BROWN
W1
RED
A1
L1
ORANGE WIRE
H6
H7
F1
GREEN WIRE
FH1
ORANGE WIRE
C1
C2
BLACK WIRE
WHITE WIRE
RED WIRE
BLUE WIRE
H3
12
H4
6
H5
6
H14
BROWN WIRE
6
H13
6
H2 6
J1, J3, J5 Red
J2, J4 Black
J6 Blue
H1
L1
avw030f.eps
Figure 5-4. Rear Input Assembly (optional)
http://www.elso.sk
5-13
8508A
Service Manual
riešenia na presné meranie™
Elso Philips Service; tel: +421 32 6582410
email: [email protected]; web: www.elso.sk
5-14
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement