I
DUAL OUTPUT POWER SUPPLY
Agilent MODEL E3630A
OPERATING AND SERVICE MANUAL
FOR INSTRUMENTS WITH SERIAL NUMBERS
KR85014528 AND ABOVE
For instruments with Serial Numbers above
KR85014528, a change page may be included.
Manual Part No. 5959-5329
April 2000
Edition 7
SAFETY SUMMARY
The following general safety precautions must be observed during all phases of operation, service, and repair of this instrument.
Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design,
manufacture, and intended use of the instrument. Agilent Technologies assumes no liability for the customer's failure to comply
with these requirements.
SAFETY SYMBOLS
BEFORE APPLYING POWER.
Verify that the product is set to match the available line voltage and that the correct fuse is installed.
GROUND THE INSTRUMENT.
This product is a Safety Class I instrument (provided with a
protective earth terminal). To minimize shock hazard, the
instrument chassis and cabinet must be connected to an
electrical ground. The instrument must be connected to the
ac power supply mains through a three-conductor power
cable, with the third wire firmly connected to an electrical
ground(safety ground) at the power outlet. Any interruption of
the protective(grounding) conductor or disconnection of the
protective earth terminal will cause a potential shock hazard
that could result in personal injury. If the instrument is to be
energized via an external autotransformer for voltage reduction, be certain that the autotransformer common terminal is
connected to the neutral(earthed pole) of the ac power lines
(supply mains).
!
Instruction manual symbol; the product
will be marked with this symbol when it is
necessary for the user to refer to the
instruction manual.
or
Indicate earth(ground) terminal.
WARNING
DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE.
Do not operate the instrument in the presence of flammable
gases or fumes.
CAUTION
KEEP AWAY FROM LIVE CIRCUITS.
Operating personnel must not remove instrument covers.
Component replacement and internal adjustments must be
made by qualified service personnel. Do not replace components with power cable connected. Under certain conditions,
dangerous voltages may exist even with the power cable
removed. To avoid injuries, always disconnect power, discharge circuits and remove external voltage sources before
touching components.
NOTE
The WARNING sign denotes a hazard. It
calls attention to a procedure, practice,
or the like, which, if not correctly performed or adhered to, could result inpersonal injury. Do not proceed beyond a
WARNING sign until the indicated conditions are fully understood and met.
The CAUTION sign denotes a hazard. It
calls attention to an operating procedure,
or the like, which, if not correctly performed or adhered to, could result in
damage to or destruction of part or all of
the product. Do not proceed beyond
CAUTION sign until the indicated conditions are fully understood and met.
The NOTE sign denotes important information. It calls attention to a procedure,
practice, condition or the like, which is
essential to highlight.
DO NOT SUBSTITUTE PARTS OR MODIFY INSTRUMENT.
Because of the danger of introducing additional hazards, do
not install substitute parts or perform any unauthorized modification to the instrument. Return the instrument to a Agilent
Technologies Sales and Service Office for service and repair
to ensure that safety features are maintained.
DO NOT SERVICE OR ADJUST ALONE.
Do not attempt internal service or adjustment unless another
person, capable of rendering first aid and resuscitation, is
present.
Instruments that appear damaged or defective should be made inoperative and secured against unintended
operation until they can be repaired by qualified service personnel.
1-2
Table of Contents
SAFETY SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
SAFETY AND EMC REQUIREMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
INSTRUMENT AND MANUAL IDENTIFICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
OPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
ACCESSORY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
LINE FUSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
INITIAL INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Mechanical Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Electrical Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
INSTALLATION DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Location and Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Outline Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Rack Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
INPUT POWER REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Power Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
OPERATING INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
TURN -ON CHECKOUT PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Tracking Ratio Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Overload Protection Circuits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Operation Beyond Rated Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Connecting Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Parallel Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Series Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
LOAD CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
PULSE LOADING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
REVERSE CURRENT LOADING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
OUTPUT CAPACITANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
REVERSE VOLTAGE PROTECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
1-3
GENERAL INFORMATION
between your instrument and the instrument described by this
manual. The Change Sheet may also contain information for
correcting errors in the manual.
INTRODUCTION
This section contains general information concerning the
E3630A triple output power supply. Included are safety considerations, safety and EMC requirements, instrument and
manual identification, option and accessory information,
instrument description, and specifications.
OPTIONS
SAFETY CONSIDERATIONS
Option No.
OE3:
OE9:
910:
Options OE3 and OE9 determine which line voltage is
selected at the factory. The standard unit is configured for 115
Vac ± 10%, 47-63 Hz input.
This product is a Safety Class I instrument, which means that
it is provided with a protective earth ground terminal. This terminal must be connected to an ac source that has a 3-wire
ground receptacle. Review the instrument rear panel and this
manual for safety markings and instructions before operating
the instrument. Refer to the Safety Summary page at the
beginning of this manual for a summary of general safety
information. Specific safety information is located at the
appropriate places in this manual.
Description
230 Vac ± 10%, 47-63 Hz Input
100 Vac ± 10%, 47-63 Hz Input
One additional operating and service manual
shipped with the power supply
ACCESSORY
The accessory listed below may be ordered from your local
Agilent Technologies Sales Office either with the power supply or separately. (Refer to the list at the rear of the manual for
address.)
SAFETY AND EMC REQUIREMENTS
This power supply is designed to comply with the following
safety and EMC(Electromagnetic Compatibility) requirements:
Agilent Part No.Description
5063-9767
Rack Kit for mounting one or two 3 1/2" high
supplies in a standard 19" rack
n
The rack mount kit is needed for rack mounting of the
E3630A power supply.
n
n
n
n
n
IEC 1010-1(1990)/EN 61010 (1993): Safety Requirements for Electrical Equipment for Measurement, Control,
and Laboratory Use
CSA C22.2 No.231: Safety Requirements for Electrical
and Electronic Measuring and Test Equipment
UL 1244: Electrical and Electronic Measuring and Testing
Equipment
EMC Directive 89/336/EEC: Council Directive entitled
Approximation of the Laws of the Member States relating
to Electromagnetic Compatibility
EN 55011(1991) Group 1, Class B/CISPR 11 (1990): Limits and Methods of Radio Interference Characteristics of
Industrial, Scientific, and Medical(ISM) Radio - Frequency Equipment
EN 50082-1(1992) /
IEC 801-2(1991): Electrostatic Discharge Requirements
IEC 801-3(1984): Radiated Electromagnetic Field
Requirements
IEC 801-4(1988): Electrical Fast Transient/Burst
Requirements
DESCRIPTION
This constant-voltage/current-limiting triple output power supply combines two 0 to ±20V tracking outputs rated at 0.5
amps with an additional single output that is rated at 0 to 6
volts and 2.5 amps. The +20V and -20V tracking outputs can
also be used in series as a single 0 to 40V 0.5-amp output.
Connections to the supply's output and to chassis ground are
made to binding posts on the front panel. The supply's three
outputs share a common output terminal, which is isolated
from chassis ground so that any one output terminal can be
grounded.
All outputs are protected against overload and short-circuit
damage. The ±20V outputs are protected by circuits that limit
the output current to 110% of its nominal maximum. The overload protection circuit for the +6V output has a current foldback characteristic that reduces the output current as an
overload increases until only 1 amp flows through a short circuit. The 6V output current limit depends on the output terminal voltage and varies linearly between 2.75 amps at 6 volts
and 1 amp at zero volts.
INSTRUMENT AND MANUAL IDENTIFICATION
A serial number identifies your power supply. The serial number encodes the country of manufacture, the week of the latest significant design change, and a unique sequential
number. The letter "KR" designates Korea as the country of
manufacture, the first one digit indicates the year (3=1993,
4=1994, and so forth), and the second two digits indicate the
week. The remaining digits of the serial number are a unique,
five-digit number assigned sequentially.
All controls, digital meter, and output terminals are located on the
front panel. One voltage control sets the 0 to 6V and another
sets the voltages of the 0 to +20V and 0 to -20V outputs simultaneously. These dual tracking outputs are made more versatile
by providing a tracking ratio control in addition to the usual voltage control. With the tracking ratio control turned fully clockwise
to its "fixed" position, the dual outputs have a fixed 1:1 tracking
ratio. As the ±20V voltage control is adjusted, the voltage of the
negative supply tracks the positive output within ±1%. Turning
the tracking ratio control away from its fully clockwise position
switches the dual tracking outputs into a variable tracking ratio
If the serial number on your supply does not agree with those
on the title page of the manual, a yellow Change Sheet is
supplied with the manual to explain the difference
1-4
mode. In this mode the voltage of the negative output can be set
lower than that of the positive output. The tracking ratio control
allows the negative supply's output to be set to any value
between a maximum that is within ±5% of the positive supply's
output and a minimum that is less than 0.5 volts. Once a ratio is
established by the tracking ratio control, the ratio of the positive
output voltage to the negative output voltage remains constant
as the ±20V voltage control varies the 0 to +20V output over its
range.
are available for nominal inputs of 100 and 230 Vac. The supply is furnished with a detachable 3-wire grounding type line
cord. The ac line fuse is in an extractor type fuseholder on the
rear heat sink.
LINE FUSE
The line fuse is located by the ac line receptacle. Check the
rating of the line fuse and replace it with the correct fuse if
necessary as indicated below. These are slow-blow fuses.
The front panel also contains a line switch, three overload
indicators for +6V output, +20V output, and -20V output, a
voltmeter and an ammeter, and three push-button meter
switches. The push buttons select one of the supply's three
outputs for display. The voltmeter and ammeter always monitor any one supply simultaneously. In addition to the standard
115 Vac ± 10% 47 to 63 Hz input, two other line voltage options
Line Voltage
100/115 Vac
230 Vac
Fuse
1.6 A
1.0 A
Agilent Part No.
2110-0918
2110-0599
SPECIFICATIONS
Table 1 lists detailed specifications for the power supply.
Table 1. Specifications
OPERATING TEMPERATURE RANGE
AC INPUT
0 to 40 oC for full rated output. At higher temperatures, out-
Standard: 115 Vac ± 10%, 47-63 Hz, 115 VA, 84 W
100 Vac ± 10%, 47-63 Hz, 115 VA, 84 W
OE9:
OE3:
230 Vac ± 10%, 47-63 Hz, 115 VA, 84 W
put current is derated linearly to 50% at 55 oC maximum
temperature.
DC OUTPUT and OVERLOAD PROTECTION
TEMPERATURE COEFFICIENT
0 to ±20 V Outputs: Maximum rated output current is 0.5 A.
Short circuit output current is 0.55 A ± 5% and a fixed current limit circuit limits the output of each supply to this maximum at any output voltage setting. Unbalanced loads within
current rating are permitted.
All Outputs:
per oC over the operating range from 0 to 40 oC
after 30 minutes warm-up.
STABILITY (OUTPUT DRIFT)
All Outputs:
0 to +6 V Output: Maximum rated output current is 2.5 A at
6 V. The maximum available output current decreases with
the output voltage setting. A current foldback circuit limits
the output to 2.75 A ± 5% at 6 volts and, with decreasing
voltage, reduces the current limit linearly to 1 A ± 15% at
zero volts (short circuited).
Less than 0.1% plus 5 mV (dc to 20 Hz) during 8 hours at constant line, load and ambient
after an initial warm-up time of 30 minutes.
LOAD TRANSIENT RESPONSE TIME
All Outputs:
TRACKING ACCURACY
The +20 V and -20 V outputs track within 1% with the
TRACKING ratio control in the Fixed position. (In variable
tracking ratio mode, the negative tracking output can be
adjusted from less than 0.5 V to within ±5% of the setting of
the positive output.)
Less than 50 msec for output recovery to
within 15 mV of nominal output voltage
following a load change from full load to half
load, or vice versa.
OUTPUT VOLTAGE OVERSHOOT
All Outputs:
LOAD REGULATION
All Outputs: Less than 0.01% plus 2 mV for a full load to
no load change in output current.
During turn-on or turn-off of ac power, output
plus overshoot will not exceed 1 V if the output control is set for less than 1 V. If the control is set for 1 V or higher, there is no
overshoot.
METER ACCURACY: ±(0.5% of output + 2 counts) at
25oC±5oC
LINE REGULATION
All Outputs:
Less than 0.02% plus 1 mV voltage change
Less than 0.01% plus 2 mV for any line voltage change within rating.
METER RESOLUTION
All Output:
PARD (Ripple and Noise)
Voltage
10 mV
Current 10 mA
DIMENSIONS
All Outputs:
Less than 0.35 mV rms/1.5 mV p-p (20 Hz-20
MHz).
Common Mode Current (CMI): Less than 1 mA for all
outputs (20 Hz-20 MHz).
212.3 mmW x 88.1 mmH x 269.2 mmD
(8.354 inW x 3.469 inH x 10.591 inD)
WEIGHT: 3.8 kg(8.4 lbs) net, 5.1 kg(11.3 lbs) shipping
1-5
INSTALLATION
cord plug appropriate for the user's location. Notify the nearest Agilent Sales and Service Office if the appropriate power
cord is not included with the supply.
INITIAL INSPECTION
Before shipment, this instrument was inspected and found to
be free of mechanical and electrical defects. As soon as the
instrument is unpacked, inspect for any damage that may
have occurred in transit. Save all packing materials until the
inspection is completed. If damage is found, a claim should
be filed with the carrier. The Agilent Technologies Sales and
Service office should be notified as soon as possible.
Mechanical Check
This check should confirm that there are no broken knobs or
connectors, that the cabinet and panel surfaces are free of
dents and scratches, and that the meter is not scratched or
cracked.
Electrical Check
Perform the TURN-ON CHECKOUT PROCEDURE in the following paragraph to confirm that the supply is operational.
Alternately, check the supply more fully using the PERFORMANCE TEST in the service information section.
INSTALLATION DATA
The instrument is shipped ready for bench operation. Before
applying power to the supply, please read the INPUT
POWER REQUIREMENTS paragraph.
Figure 1. Outline Diagram
OPERATING INSTRUCTIONS
Location and Cooling
This instrument is air cooled. Sufficient space should be
allowed so that a free flow of cooling air can reach the sides
and rear of the instrument when it is in operation. It should be
used in an area where the ambient temperature does not
INTRODUCTION
The following steps describe the use of the front panel controls and indicators illustrated in Figure 2 and serve as a brief
check that the supply is operational. Follow this checkout procedure or the more detailed performance test of service information section when the instrument is received and before it
is connected to any load equipment.
exceed 40oC.
Outline Diagram
Figure 1 illustrates the outline shape and dimensions of the
supply.
Rack Mounting
This supply may be rack mounted in a standard 19-inch rack
panel either by itself or alongside a similar unit. Please see
the ACCESSORY, page 1-4, for available rack mounting
accessory. The rack-mounting kit includes complete installation instructions.
INPUT POWER REQUIREMENTS
Depending on the line voltage option ordered, the supply is
ready to be operated from one of the power sources listed in
Table 1. A label on the rear heat sink shows the nominal input
voltage set for the supply at the factory.
Power Cable
To protect operating personnel, the supply should be
grounded. This supply is equipped with a three conductor
power cable. The third conductor is the ground conductor and
when the cable is plugged into an appropriate receptacle, the
supply is grounded.
The power supply is equipped at the factory with a power
Figure 2. Front-Panel Controls and Indicators
1-6
tor the 0 to 40V output voltage, add the voltmeter readings of
the +20V and -20V output and use either the +20V or the 20V meter to measure the current.
Before applying power to the supply, check the label on the
heat sink to make certain that the supply's line voltage option
agrees with the line voltage to be used. If the option does not
correspond to your line voltage, refer to paragraph "LINE
VOLTAGE OPTION CONVERSION" in the service section
before applying power.
Tracking Ratio Control
With the Tracking Ratio control in the Fixed position, the voltage of the -20V supply tracks that of the +20V supply within
1% for convenience in varying the symmetrical voltages
needed by operational amplifiers and other circuits using balanced positive and negative inputs.
TURN -ON CHECKOUT PROCEDURE
Turn the Tracking Ratio control counter clockwise out of the
Fixed position to set the voltage of the -20V supply lower than
that of the +20V supply. The negative supply can be set from
a minimum of less than 0.5 volts to a maximum within 5% of
the +20V supply's output. Once this is done, the ±20V voltage
control still controls both outputs and maintains a constant
ratio between their voltages.
a. Connect line cord to power source and turn LINE
switch
on.
b. Push +6V METER switch
and, with no load connected, vary +6V VOLTAGE control
over its range
and check that the voltmeter responds to the control
setting and the ammeter indicates zero.
c.
Set the +6V VOLTAGE control to 6 volts and short the
+6V output terminal
to COM (common) terminal
with an insulated test lead. The ammeter should
indicate a short-circuit output current of approximately
1.0 A. Remove the short from the output terminals.
Overload Protection Circuits
±20-Volt Current Limit. The +20V and -20V outputs are individually protected against overload or short circuit damage by
separate current limit circuits to limit the output current to 0.55
A ± 5%. (This is 110% of the maximum rated output.) If a single load is connected between the +20V and -20V outputs,
the circuit set for the lesser current limit will limit the output.
No deterioration of supply performance occurs if the output
current remains below the current limit setting.
d. Push the +20V METER switch
and turn Tracking
Ratio control
fully clockwise to the Fixed position.
With no load connected, vary ±20V VOLTAGE control
over its range and check that the voltmeter
responds to the control setting and the ammeter indicates zero.
+6V Current Foldback. The overload and short-circuit protection circuit for the +6V output reduces the output current
limit as the output terminal voltage decreases. (The operating
region of the +6V output is enclosed by heavy lines in Figure
4.) The maximum rated output current is 2.5 A and the current
limit is factory-adjusted to operate at 2.75 A ± 5% when the
output is 6 volts. At lower output voltages, the circuit reduces
the maximum obtainable output current linearly until 1 A ±
15% flows when the output is shorted. The short-circuit current can not be adjusted.
e. Set the ±20V VOLTAGE control
to 20 volts and
short the +20V output terminal
to the COM terminal
with an insulated test lead. The ammeter should
indicate a short-circuit output current of 0.55 A ± 5%.
Remove the short from the output terminals.
f.
Repeat steps (d) and (e) for -20 V output.
g. Adjust the +20V output to 20 volts. Then push -20V
METER switch and check the effect of the Tracking
Ratio control on the voltage of the -20V output. The 20V output should be adjustable from less than 0.5
volts to a maximum of 19 to 21 volts.
If this brief checkout procedure or later use of the supply
reveals a possible malfunction, see the service information
section for detailed test, troubleshooting, and adjustment procedures.
During the actual operation of the ±20V and +6V outputs, if a
load change causes the current limit to be exceeded, the OL
LED is lighted. If overload conditions occur, the ±20V supplies
will protect the load by limiting the current to 0.55 A and the
+6V supply will protect the load by reducing both voltage and
current simultaneously along the foldback locus as shown in
Figure 4. The ±20V and +6V supplies are self restoring; that
is, when the overload is removed or corrected, the output
voltage is automatically restored to the previously set value.
OPERATION
This power supply can be operated individually or in parallel
or series with another supply (see Parallel and Series Operation paragraphs). All output terminals are isolated from
ground. The ±20V and +6V outputs use a single common output terminal. This common (COM) terminal or any one of the
other output terminals may be grounded to the chassis at the
front panel ground terminal (
in Figure 2), or all outputs may
be left floating. Loads can be connected separately between
each of the 0 to ±20V output terminals and the COM terminal,
or between the -20V and the +20V terminals for a 0 to 40V
output. Each output voltage or current can be quickly selected
for monitoring with the push-button meter switches. To moni-
Operation Beyond Rated Output
The supply may be able to provide voltages and currents
greater than its rated maximum outputs if the line voltage is at
or above its nominal value. Operation can be extended up to
5% over the rated output without damage to the supply, but
performance can not be guaranteed to meet specifications in
1-7
necessary to fulfill the total current demand.
Series Operation
Series operation of two or more power supplies can be
accomplished up to the output isolation rating of any one supply to obtain a higher voltage than that available from a single
supply. Series connected supplies can be operated with one
load across both supplies or with a separate load for each
supply. The power supply has a reverse polarity diode connected across the output terminals so that if operated in
series with other supplies, damage will not occur if the load is
short-circuited or if one supply is turned on separately from its
series partners. When this connection is used, the output voltage is the sum of the voltages of the individual supplies. Each
of the individual supplies must be adjusted in order to obtain
the total output voltage.
LOAD CONSIDERATIONS
This section provides information on operating your supply
with various types of loads connected to its output.
PULSE LOADING
Figure 3. Current Limit Characteristic of the 6V Supply
The power supply will automatically cross over from constantvoltage to current-limit operation in response to an increase in
the output current over the preset limit. Although the preset
limit may be set higher than the average output current, high
peak currents (as occur in pulse loading) may exceed the preset current limit and cause crossover to occur and degrade
performance.
this region. If the line voltage is maintained in the upper end
of the input voltage range, however, the supply probably will
operate within its specifications
Connecting Load
Each load should be connected to the power supply output
terminals using separate pairs of connecting wires. This will
minimize mutual coupling effects between loads and takes full
advantage of the low output impedance of the supply. Load
wires must be of adequately heavy gauge to maintain satisfactory regulation at the load.
REVERSE CURRENT LOADING
An active load connected to the supply may actually deliver a
reverse current to the supply during a portion of its operating
cycle. An external source can not be allowed to pump current
into the supply without risking loss of regulation and possible
damage to the output capacitor of the supply. To avoid these
effects, it is necessary to preload the supply with a dummy
load resistor so that the supply delivers current through the
entire operating cycle of the load devices.
Each pair of connecting wires should be as short as possible
and twisted or shielded to reduce noise pick-up. If a shield is
used, connect one end to the supply ground terminal and
leave the other end unconnected.
OUTPUT CAPACITANCE
If load considerations require locating output power distribution terminals at a distance from the power supply, then the
power supply output terminals should be connected to the
remote distribution terminals by a pair of twisted or shielded
wires and each load should be connected to the remote distribution terminals separately.
An internal capacitor across the output terminals of the supply
helps to supply high-current pulses of short duration during
constant-voltage operation. Any capacitance added externally
will improve the pulse current capability, but will decrease the
load protection provided by the current limiting circuit. A highcurrent pulse may damage load components before the average output current is large enough to cause the current limiting circuit to operate.
Parallel Operation
Two or more supplies can be connected in parallel to obtain a
total output current greater than that available from one supply. The total output current is the sum of the output currents
of the individual supplies. The output voltage controls of one
power supply should be set to the desired output voltage, and
the other supply set for a slightly larger output voltage. The
supply set to the lower output voltage will act as a constant
voltage source, while the supply set to the higher output will
act as a current-limited source, dropping its output voltage
until it equals that of the other supply. The constant voltage
source will deliver only that fraction of its rated output current
REVERSE VOLTAGE PROTECTION
A diode is connected across the output terminals with reverse
polarity. This diode protects the output electrolytic capacitors
and the series regulator transistors from the effects of a
reverse voltage applied across the output terminals. Since
series regulator transistors can not withstand reverse voltage
either, diodes are also connected across them. When operating supplies in parallel, these diodes protect an unenergized
supply that is in parallel with an energized supply.
1-8
Figure 4. Reverse Current Loading Solution
1-9
SERVICE INFORMATION
Figure A-1. Block Diagram
PRINCIPLES OF OPERATION
By comparing its output to a high-stability reference, the 0 to
+6-volt regulator holds its output voltage at the value determined by a front panel control. Any error in the actual output
as compared to the desired output is amplified by an operational amplifier and applied as feedback to control the conduction of a series regulator transistor. As a result, the voltage
across the series transistor varies so as to hold the output
voltage constant at the desired level. The high gain of the
voltage comparison amplifier and the stability of the reference
voltage ensure that input voltage or load current variations
have little effect on the output voltage.
(Block Diagram Overview)
This section presents the principles of operation of the
E3630A Triple Output Power Supply. Throughout this discussion, refer to both the block diagram of Figure A-1 and the
schematic diagrams at the rear of the manual.
The two primary windings of the power transformer are connected in one of three different ways by setting the two slide
switches mounted on the circuit board. These switches select
one of the nominal ac input voltages for which the supply is
designed: 100 V, 115 V, or 230 V.
The 0 to +6-volt output is protected by a current foldback limiter to minimize dissipation in the series regulator transistor
during overloads. In a current foldback circuit, the current limit
depends on the output terminal voltage. The current limit
ranges from 2.75 A ± 5% at 6 volts to 1 A ± 15% with the output shorted. The operating region of the +6-volt regulator out-
The transformer secondaries, together with rectifiers and
capacitor filters, provide raw dc for the three output regulator
circuits and for another regulator that provides reference and
bias voltages to the output regulators.
A-1
put is enclosed by a heavy line in Figure 3 of the operating
section. If the operating point reaches the diagonal current
limit line, a decrease in load resistance moves the operating
point down the line, reducing the output voltage and current.
Current foldback is controlled by a second operational amplifier (current comparison amplifier) in the regulator that monitors the dc output current. This current comparison amplifier
takes control of the output away from the voltage comparison
amplifier when the current reaches the design limit. Removing
the overload restores constant voltage operation automatically.
The reference and bias supply powers the operation amplifiers and provides reference and bias voltages for the output
regulators. The display power circuit provides voltage which
is used by the A/D converter and display.
The turn-on/turn-off control circuit prevents output transients
when the supply is turned on or off. It does this by delaying
the application of certain bias and reference voltages at turnon and removing them shortly after turn-off.
Three meter push-button switches select which of the supplies has its output voltage and current indicated on the front
panel meters.
The 0 to +20-volt regulator has a fixed current limit at 105% of
its 0.5 amp maximum rated output. The input ac line voltage
is first applied to the preregulator which operates in conjunction with the SCR control circuit (preregulator control circuit)
to rectify the tap switched AC voltage. This preregulator minimizes the power dissipated in the series regulating elements
by controlling the dc level across the input filter capacitor,
depending on the output voltage. To achieve this, tap switching is accomplished by two SCRs and one bridge diode
(CR28, CR32 and CR26) and the SCR control circuit. This circuit allows the input capacitor to charge to one of two discrete
voltage levels depending on the output required.
Diode CR2, CR3, and CR4 are connected across the output
terminals in reverse polarity. They protect the output electrolytic capacitor and the series regulator transistors from a
reverse voltage applied across the output terminals.
MAINTENANCE
INTRODUCTION
This section provides performance test, troubleshooting information, and adjustment and calibration procedures. The following operation verification tests comprise a short procedure
to verify that the power supply is performing properly, without
testing all specified parameters.
When output voltage exceeds the reference level, the SCR
control circuit fires two SCRs that cause the input capacitor to
be charged to the voltage which is necessary for full output of
the supply. When the two SCRs are not fired, the bridge diode
CR26 conducts and half the voltage is applied to series pass
transistor Q9.
If a fault is detected in the power supply while making the
performance check or during normal operation, proceed to
the troubleshooting procedures. After troubleshooting, perform any necessary adjustments and calibrations. Before
returning the power supply to normal operation, repeat the
performance check to ensure that the fault has been properly
corrected and that no other faults exist.
The 0 to -20-volt regulator is, in turn, similar to the +20-volt
regulator except that it resembles a complementary mirror
image of the latter. The output voltages of the +20-volt and 20-volt supplies are both set by the same front panel control
and track each other within 1% in the fixed tracking ratio
mode. Precise tracking of the two outputs is achieved by
controlling the positive output conventionally and using that
output as the reference voltage for the negative output.
Test Equipment Required
The following Table A-1 lists the equipment required to perform the various procedures described in this section.
Table A-1. Test Equipment Required
TYPE
REQUIRED CHARACTERISTICS
USE
RECOMMENDED
MODEL
Oscilloscope
Sensitivity : 100 V
Bandwidth : 20 MHz/100 MHz
Display transient response and ripple
and noise waveforms.
RMS Voltmeter
True rms, 20 MHz bandwidth
Sensitivity : 1 mV
Accuracy : 5%
Measure rms ripple and noise
voltage.
Multimeter
Resolution : 100 nV
Accuracy : 0.0035%
Measure dc voltages.
Agilent 34401A
Electronic Load
Voltage Range : 240 Vdc
Current Range : 10 Adc
Open and short switches
Transient on/off
Measure load and line regulation.
Agilent 6063A
Resistive Loads (RL)
40 20 W, 2.4 20 W
Measure ripple and noise.
A-2
Agilent 54600A
Table A-1. Test Equipment Required (Cont’d)
Current Sampling
Resistor (Shunt)
100 mΩ 0.1% 15 W
Measure output current
Variable Voltage
Auto Transformer
Range : 85-130 and 200-260
Volts
Vary ac input.
General Measurement Techniques
Operation Verification Tests
The following tests assure that the power supply is performing properly. They do not, however, check all the specified parameters tested in the complete performance test
described below. Proceed as follows:
a. Perform turn-on checkout procedure given in page 1-7.
b. Perform the load regulation performance tests given in
the following paragraphs.
Connecting Measuring Devices. To achieve valid results
when measuring load regulation, ripple and noise, and transient response time of the supply, measuring devices must be
connected as close to the output terminals as possible. A
measurement made across the load includes the impedance
of the leads to the load. The impedance of the load leads can
easily be several orders of the magnitude greater than the
supply impedance and thus invalidate the measurement. To
avoid mutual coupling effects, each measuring device must
be connected directly to the output terminals by separate
pairs of leads.
Line Voltage Option Conversion
To convert the supply from one line voltage option to another,
the following three steps are necessary:
a. After making certain that the line cord is disconnected
from a source of power, remove the top cover from the
supply and set the two sections of the line voltage selector switch for the desired line voltage (see Figure A-2).
b. Check the rating of the installed fuse and replace it with
the correct value, if necessary. For Option OE3, use a
slow-blow 1.0-amp fuse. For standard and Option OE9,
use a slow-blow 1.6-amp fuse.
c. Mark the instrument clearly with a tag or label indicating
the correct line voltage to be used.
When performance measurements are made at the front terminals (Figure A-3) the load should be plugged into the front
of the terminals at (B) while the monitoring device is connected to a small lead or bus wire inserted through the hole in
the neck of the binding post at (A). Connecting the measuring
device at (B) would result in a measurement that includes the
resistance of the leads between the output terminals and the
point of connection.
Figure A-3. Front Panel Terminal Connections
Figure A-2. Line Voltage Selector (set for 115 Vac)
Selecting Load Resistors. Power supply specifications are
checked with a full load resistance connected across the supply output. The resistance and wattage of the load resistor,
therefore, must permit operation of the supply at its rated output voltage and current. For example, a supply rated at 20
volts and 0.5 amperes would require a load resistance of 40 Ω
at the rated output voltage. The wattage rating of this resistor
would have to be at least 20 watts.
PERFORMANCE TESTS
The following paragraphs provide test procedures for verifying the power supply's compliance with the specifications of
Table 1. Proceed to the troubleshooting procedures if you
observe any out of specification performance.
Electronic Load. Some of the performance test procedures
use an electronic load to test the supply quickly and accurately. An electronic load is considerably easier to use than a
load resistor. It eliminates the need for connecting resistors or
rheostats in parallel to handle the power, it is much more stable than a carbon-pile load. It is easier to switch between load
conditions as required for the load regulation and load transient response tests.
Before applying power to the supply, make certain
that its line voltage selector switch (S2) is set for the
line voltage to be used. (See CAUTION notice in
operating section for additional information on S2.)
A-3
Output Current Measurement. For accurate output current
measurements, a current sampling resistor should be inserted
between the load and the output of the supply. To simplify
grounding problems, one end of this sampling resistor should be
connected to the same output terminal of the supply which will
be shorted to ground. An accurate voltmeter is then placed
across the sampling resistor and the output current calculated by
dividing the voltage across the sampling resistor by its ohmic
value. The total resistance of the series combination should be
equal to the full load resistance as determined in the preceding
paragraphs. Of course, if the value of the sampling resistor is
very low when compared to the full load resistance, the value of
the sampling resistor may be ignored. The meter shunt recommended in Table A-1, for example, has a resistance of only 100
m and can be neglected when calculating the load resistance
of the supply. Figure A-4 shows a four terminal meter shunt. The
load current through a shunt must be fed from the extremes of
the wire leading to the resistor while the sampling connections
are made as close as possible to the resistance portion itself.
Variable Tracking Ratio
e. Leave the ±20V VOLTAGE control set as in step (d), and
use a DVM to monitor the voltage of the -20V supply
while adjusting the TRACKING RATIO control over its
VARIABLE range. The -20V supply should be capable of
being adjusted from less than 0.5 volts to between 19 to
21 volts. Return the TRACKING RATIO control to the
FIXED position.
Leave the TRACKING RATIO control in the FIXED
position throughout the reminder of the performance
test.
Rated Output and Ammeter Accuracy
f.
Connect two 40 20 W load resistors across both of the
20V outputs of the supply and set the ±20V VOLTAGE
control for ±20V outputs. (All supplies must be fully
loaded while checking the rated output voltage and current of each supply.)
g. Connect the test setup shown Figure A-5 to the +6V output.
Make the total resistance of RL and the current sampling
resistor equal to 2.4 to permit operating the output at full
load. RL should have a power rating of at least 20 watts.
h. Close the switch and set the +6V VOLTAGE control so that
the DVM indicates a voltage drop across the current sampling resistor that corresponds to a current of 2.5 amps.
i. Push the +6V METER switch and verify that the front
panel ammeter indication is within ±(0.5%+2 counts) of
2.5 amps (2.47A to 2.53A).
j. Check the rated output and ammeter accuracy of the
+20V and -20V supplies similarly by connecting the test
setup of Figure A-5 to each output in turn. For each 20V
supply: make the total resistance of RL and the current
sampling resistor 40 , set the ±20V VOLTAGE control
for a current indication on the DVM of 0.5 A, check that
the panel meter indication is within ±(0.5%+2 counts) of
0.5 A (0.48A to 0.52A).
Figure A-4. Current Sampling Resistor Connections
Rated Output, Tracking, Meter Accuracy, and Current Limit
To check that all supplies will furnish their maximum rated
output voltage and current, that the ±20V outputs track each
other, that the front panel meters are accurate, and that the
current limit circuits function, proceed as follows:
Voltmeter Accuracy
a. With no loads connected: turn on the supply, connect a
digital voltmeter between the +20V terminal and common
(COM), and set the ±20V VOLTAGE control so that the
DVM indication is as near as possible to 17 volts.
b. Push the +20V METER switch on and check the front
panel voltmeter indication. It should be within ±(0.5% +2
counts) of the DVM indication (16.90V to 17.10V).
c. Set the TRACKING RATIO control to the FIXED position,
and check the +20V and -20V ranges of the front panel
voltmeter similarly by connecting the DVM to each of
these outputs in turn, setting the ±20V VOLTAGE control
for a 20 volts DVM indication, and verifying that the panel
meter is accurate within ±(0.5%+ 2 counts) (19.7V to
20.3V).
Tracking
d. Connect the DVM to the +20V output, set the ±20V
VOLTAGE control for a DVM indication of 20 volts, and
reconnect the DVM to the -20V output without disturbing
the voltage control. The voltage at the -20V output should
be within 1% of the +20V output (19.8V to 20.2V).
Figure A-5. Output Current, Test Set UP
A-4
Line Regulation (Source Effect)
Current Limit
k. Disconnect all loads from the supply.
l. Connect the test setup shown in Figure A-5 to the +20volt output. Substitute a short for RL and leave the load
circuit switch open.
m. Set the voltage of the ±20V supplies to 20 volts.
n. Close the load switch and determine the current flow
through the current sampling resistor (meter shunt) by
measuring its voltage drop with the DVM. The current
should be 0.55A±5% (0.5225A to 0.5775A).
o. Check the current limit of the -20V supply in the same
way. Its short-circuit current should also be 0.55A±5%
(0.5225A to 0.5775A).
p. Connect the test setup shown in Figure A-5 to the +6V
output. Close the switch, set the total resistance of RL and
the current sampling resistor to an initial value of 2.4 Ω or
greater, and set the output voltage to 6 volts.
q. Reduce the value of RL gradually while observing the output current indicated by the DVM. The current should
increase to a maximum of 2.75A±5% (2.6125A to
2.8875A) before it begins to decrease.
r. Connect a short across RL and then recheck the current
indicated by the DVM. The short-circuit current of this output should be 1A±15% (0.85A to 1.15A). Disconnect the
test setup from the supply.
Definition: The change, EOUT, in the static value of dc output
voltage resulting from a change in ac input voltage from a
minimum to a maximum value (±10% of nominal voltage).
To check the line regulation:
a. Connect a variable autotransformer between the input
power source and the power supply line plug.
b. Connect the test equipment across the output of the
+20V supply as shown in Figure A-6. Operate the electronic load in constant current mode and set its current to
the full rated value of the +20V supply.
c. Adjust the autotransformer for a low line input (-10% of
nominal voltage).
d. Turn on the power, adjust the output of the supply to its
maximum rated voltage, and record the DVM indication.
e. Adjust the autotransformer for high line voltage input
(+10% of nominal voltage) and recheck the DVM indication. It should be within 0.01% plus 2mV of the reading in
step (d).
f. Repeat steps (b) through (e) for each of the remaining
supply outputs.
Ripple and Noise
Definition: Ripple and noise are measured in the rms or peakto-peak value over a 20 Hz to 20 MHz bandwidth. Fluctuations
below the lower frequency limit are treated as drift.
Load Regulation (Load Effect)
Definition: The change, EOUT, in the static value of dc out-
RMS Measurement
The rms measurement is not an ideal representation of the
noise, since fairly high output noise spikes of short duration
could be present in the ripple and not appreciably increase
the rms value.
put voltage resulting from a change in load resistance from
open circuit to the value that yields maximum rated output
current (or vice versa).
To check the load regulation:
a. Connect the test equipment across the output of the
+20V supply as shown in Figure A-6. Operate the electronic load in constant current mode and set its current to
the full rated value of the +20V supply.
b. Turn on the supply and adjust its voltage to its maximum
rated value.
c. Record the voltage indicated on the DVM.
d. Operate the electronic load in open (input off) mode and
recheck the DVM indication after reading settles. It should
be within 0.01% plus 2mV of the reading in step (c).
e. Repeat steps (a) through (d) for each of the remaining
supply outputs.
To measure the ripple and noise of the rms value on each
output supply output:
a. Connect the test equipment across the output of the
+20V supply as shown in Figure A-7.
b. Turn on the supply and push +20V METER switch.
c. Turn up output voltage to the full rated value.
d. Check that the rms noise voltage at the true rms voltmeter is less than 0.35mV.
e. Repeat for the remaining supply outputs.
Figure A-7. Ripple and Noise rms Measurement Test
Setup
Figure A-6. Basic Test Setup
A-5
Peak-to-Peak Measurement
The peak-to-peak measurement is particularly important for
applications where noise spikes could be detrimental to a
sensitive load, such as logic circuitry.
d. Turn on the supply.
e. Record the voltage across RS and convert it to current by
dividing this voltage by RS.
f. Check that the current is less than 1 A.
To measure the ripple and noise of the peak-to-peak value on
each output supply output:
a. Connect the test equipment across the output of the
+20V supply as shown in Figure A-7, but replace the true
rms voltmeter with the oscilloscope.
b. Turn on the supply and push +20V METER switch.
c. Turn up output voltage to the full rated value.
d. Set the oscilloscope to AC mode and bandwidth to 20
MHz.
e. Check that the peak-to-peak noise is less than 1.5 mV.
f. Repeat for the remaining supply outputs.
Load Transient Response Time
Definition : This is the time for the output voltage to return to
within a specified band around its voltage following a change
from full load to half load or half load to full load.
To measure the load transient response time:
a. Connect the test equipment across the output of the
+20V supply as shown in Figure A-6, but replace the
DVM with the oscilloscope. Operate the electronic load in
constant current mode.
b. Turn on the supply.
c. Turn up output voltage to the full rated value.
d. Set the electronic load to transient operation mode
between one half of supply's full rated value and supply's
full rated value at a 1 KHz rate with 50% duty cycle.
e. Set the oscilloscope for ac coupling, internal sync and
lock on either the positive or negative load transient.
f. Adjust the oscilloscope to display transients as in Figure
A-8.
g. Check that the pulse width (t2-t1) of the transients at 15
mV from the base line is no more than 50 sec as shown.
h. Repeat for the remaining supply outputs.
Common Mode Current (CMI)
Definition : Common mode current is that ac current component which exists between any or all supply or output lines
and chassis ground.
To measure the common mode current:
a. Connect the full load for +6V output.
b. Connect a 100 k resistor(RS) and a 2200 pF capacitor
in parallel between common terminal(COM) and chassis
ground.
c. Connect the DVM across RS.
Figure A-8. Load Transient Response Time Waveform
A-6
Stability (Drift)
Definition: The change in output voltage (dc to 20 Hz) for the
first 8 hours following a 30-minute warm-up period with constant input line voltage, constant load resistance and constant
ambient temperature.
Before applying power to the supply, make certain
that its line voltage selector switch (S2) is set for the
line voltage to be used.
To measure the stability:
a. Connect the test equipment across the output of the
+20V supply as shown in Figure A-6.
b. Operate the electronic load in constant current mode and
set its current to the full rated value of power supply.
c. Turn on the supply.
d. Turn up output voltage to the full rated value as read on
the digital voltmeter.
e. After a 30-minute warm-up, note the voltage on DVM.
f. The output voltage reading should deviate less than 0.1%
plus 5 mV from the reading obtained in step e over a
period of 8 hours.
g. Repeat for the remaining supply outputs.
Initial Troubleshooting Procedure
If a malfunction is found, follow the steps below:
a. Disconnect input power from the supply and remove all
loads from the output.
b. Table A-2 lists the symptoms and probable causes of several possible troubles. If the symptoms is one of those
listed, make the recommended checks.
c. If none of the symptoms of Table A-2 apply, proceed to
Table A-3. This table provides an initial troubleshooting
procedure that also directs you to the more detailed procedures which follow it.
The numbered test points referred to in the troubleshooting
procedures are identified on the circuit schematic at the rear
of the manual.
TROUBLESHOOTING
Before attempting to troubleshoot the power supply, ensure
that the fault is with the supply and not with an associated
piece of equipment. You can determine this without removing
the covers from the power supply by using the appropriate
portions of the "Performance Test" paragraph.
Open Fuse Troubleshooting
Although transients or fatigue can cause a fuse to blow, it is a
good idea to inspect the unit for obvious shorts such as damaged wiring, charred components, or extraneous metal parts
or wire clippings in contact with circuit board conductors
before replacing the fuse. The rating of the correct replacement fuse depends on the line voltage option of the instrument: for Option OE3, use a slow-blow 1.0-amp fuse and
standard and Option OE9, use a slow-blow 1.6-amp fuse.
Table A-2. Miscellaneous Troubles
SYMPTOM
CHECK - PROBABLE CAUSE
High ripple
a. Check operating setup for ground loops.
b. Check main rectifiers(CR1, CR25, CR26) for open.
c. Supply may be operating in current limit mode. Check current limit adjustment, steps (k)
thru (r) on page A-5.
Will not current limit
Check for open OR-gate diodes (CR7, CR11, CR18) or defective current limit amplifier
(U2, U6, U8).
Poor load and line regulation
a. Check bias and reference voltages, Table A-4.
b. Check main rectifiers and filters for opens.
Oscillation or poor transient
response time
a. High frequency oscillations (above 50 kHz) can be caused by an open C11, C20, or C25.
b. A defective output capacitor (C2, C3, or C4) can cause oscillations in one of many frequency
ranges.
c. Oscillation only in the current limiting mode can be caused by an open C12, C19, or C24.
Transient voltage overshoot at
turn-on or turn-off
a. Overshoot only in the -20V supply can be caused by a shorted Q3.
b. Overshoot in all three supply outputs can be caused by an open Q2 or a shorted Q6.
Excessive heat
a. Check preregulator control circuit. Refer to Table A-8 and Table A-9.
b. Check CR27, CR28, CR31, CR32 for short.
Output Voltage clamped
above 10V for ± 20V output
Check preregulator control circuit. Refer to Table A-8 and Table A-9.
A-7
Table A-3. Initial Trobleshooting Procedure
STEP
1
ACTION
Check output voltage of +20V
supply.
RESPONSE
a. Normal
b. Zero volts
c.
2
Check output voltage of -20V
supply in fixed tracking ratio
mode.
NEXT ACTION
a. Proceed to step (2).
b. Check ac line fuse (F1). If blown, proceed to "Open Fuse
Troubleshooting" paragraph. If not blown, check bias
and reference voltages (Table A-4).
Output voltage lower or c. Check bias and reference voltages (Table A-4).
higher than rating
a. Normal
b. High, low, or zero output voltage.
3
Check output of +6V supply.
a. Normal
b. High, low, or zero output voltage.
a. If +20V and -20V outputs are both normal with no load, a
supply might be current limiting under load. To check this
adjustment see steps (l) thru (p) on page A-4.
b. Proceed to -20V supply troubleshooting.
a. If the output of this supply is normal unloaded but its voltage falls when loaded, check the current limit adjustment, steps (q) thru (t) on page A-4.
b. Proceed to Table A-7.
Table A-4. Bias and Reference Voltage Check
STEP
ACTION
RESPONSE
NEXT ACTION
1
Check +12V bias.
a. Normal (+12V ± 5%)
a. Proceed to step (3).
b. Voltage high
b. Check U3 for short.
c. Output voltage lower or c. Check U3 for open.
higher than rating
Note: A short within U2, U6, U8, U9 or U14 can cause low
+12V or -12V bias voltages.
2
Check -5V reference.
a. Normal (-5V ± 2%)
b. Voltage high
c. Voltage low
a. Proceed to step (3).
b. Check U5 for open.
c. Check U5 and Q2 for short.
3
Check -12V bias.
a. Normal (-12V ± 5%)
a. Proceed to +20V supply troubleshooting, Table A-5.
b. Check U1 for short.
b. High voltage
c.
c.
Check U1 for open.
Low voltage
Table A-5. +20V Supply Troubleshooting
SYMPTOM
High output voltage
(higher than rating)
STEP - ACTION
RESPONSE
PROBABLE CAUSE
1. Attempt to turn off Q9 by a. Output voltage remains high.
a. Q9 shorted.
shorting emitter-to-base b. Output voltage becomes near zero b. Remove short and proceed to step
of Q9.
volt.
(2).
2. Measure voltage at
base of Q5.
a. Measured voltage is less than 0
volt.
b. Measured voltage is more than 0
volt.
A-8
a. Check for open CR13 or R36 and
check for defective U6A.
b. Check for defective Q5.
Table A-5. +20V Supply Troubleshooting (Cont’d)
Low output voltage
(lower than rating)
1. Measure voltage at the a. Measured voltage is less than 0
base of Q5.
volt.
b. Measures voltage is more than 0
volt.
a. Check for open Q9, Q6, R26, or
CR5.
b. Proceed to step (2).
2. Eliminate current limit
a. Output voltage increases.
circuit as a source of
b. Output voltage remains low.
trouble by disconnecting
anode of CR11.
a. Check for U6B defective.
b. Reconnect lead and proceed to
step (3).
3. Measure voltage at pin 3 a. Measured voltage is near
of U6.
-0.7V.
b. Measured voltage is zero volt.
a. Check for defective U6A.
c.
Measured voltage is near
+0.7V.
b. Check for CR14 or CR15 shorted.
c. Check for open R39, shorted R36,
or leaky or shorted C7.
Table A-6. -20V Supply Troubleshooting
SYMPTOM
STEP - ACTION
RESPONSE
PROBABLE CAUSE
The +20V supply must operate properly before troubleshooting the -20V supply.
High output voltage
(more than 1%
greater than +20V
supply in fixed
tracking ratio mode)
1. Attempt to turn off Q8 by a. Output voltage remains high.
a. Q8 shorted.
shorting emitter-to-base b. Output voltage becomes near zero b. Remove short and proceed to
of Q8.
volt.
step (2).
2. Measure voltage at
base of Q7.
a. Measured voltage is more than
0 volt.
b. Measured voltage is less than
0 volt.
a. Check for open CR20 or R14 and
check for defective U8A.
b. Check for defective Q7.
Low output voltage
(more than 1% lower
than +20V supply in
fixed tracking ratio
mode)
1. Measure voltage at the
base of Q7.
a. Measured voltage is more than 0
volt.
b. Measured voltage is less than
0 volt.
a. Check for open Q8, Q3, and R24.
b. Proceed to step (2).
2. Eliminate current limit
a. Output voltage increases.
circuit as a source of
b. Output voltage remains low.
trouble by disconnecting
anode of CR18.
a. Check for U8B defective.
b. Reconnect lead and proceed to
step (3).
a. Check for defective U8A.
3. Measure voltage at pin 3 a. Measured voltage is near
of U8.
+0.7V.
b. Measured voltage is zero volt.
c.
Measured voltage is near
-0.7V.
A-9
b. Check for shorted CR21 and
CR22.
c. Check for open R15, shorted R41,
or leaky or shorted C6.
Table A-7. +6V Supply Troubleshooting
SYMPTOM
STEP - ACTION
RESPONSE
PROBABLE CAUSE
The +20V supply must operate properly before troubleshooting the -20V supply.
High output voltage
(higher than rating)
1. Attempt to turn off Q1 by a. Output voltage remains high.
a. Q1 shorted.
shorting emitter-to-base b. Output voltage becomes near zero b. Remove short and proceed to
of Q1.
volt.
step 2.
2. Measure voltage at
base of Q4.
Low output voltage
(lower than rating)
1. Measure voltage at the
base of Q4.
a. Measured voltage is more than
-0.6V.
b. Measured voltage is less than
-0.6V.
a. Check for defective Q4.
a. Measured voltage is less than
-0.6V.
b. Measured voltage is more than
-0.6V.
a. Check for open Q1, Q6, R25, or
CR5.
b. Proceed to step (2).
b. Check for open CR6, R11 and
check for defective U2A.
2. Eliminate current limit
a. Output voltage increases.
circuit as a source of
b. Output voltage remains low.
trouble by disconnecting
anode of CR7.
a. Check for U2B defective.
b. Reconnect lead and proceed to
step (3).
3. Measure voltage at
pin 3 of U2.
a. Check for defective U2A.
a. Measured voltage is near
-0.7V.
b. Measured voltage is zero volt.
c. Measured voltage is near
+0.7V.
b. Check for CR9 and CR10 shorted.
c. Check for open R29, shorted R11,
or leaky or shorted C5.
Table A-8. +20V Preregulator/Control Circuit Troubleshooting
STEP
ACTION
RESPONSE
PROBABLE CAUSE
Set output voltage at 12V+0.5V.
1
Measure pin 1 of U14.
a. Measured voltage is -12V.
b. Measured voltage is near
+4.3V.
a. Proceed to step (2).
b. Check for defective U14A.
2
Measure pin 1 of U13.
a. Measured voltage is near +1V
b. Measured voltage is near 0V.
a. Check for defective U13 or
CR12.
b. Check for open Q11 or R81.
a. Measured voltage is near +1V
b. Measured voltage is near 0V.
a. Check for defective U11.
b. Check for open Q11 or R82.
3
Measure pin 1 of U11.
Table A-9. -20V Preregulator/Control Circuit Troubleshooting
STEP
ACTION
RESPONSE
PROBABLE CAUSE
Set output voltage at -12V-0.5V.
1
Measure pin 7 of U14.
a. Measured voltage is -12V.
b. Measured voltage is near
+4.3V.
a. Proceed to step (2).
b. Check for defective U14B.
2
Measure pin 1 of U12.
a. Measured voltage is near +1V
a. Check for defective U12 or
CR31.
b. Check for open Q10 or R56
b. Measured voltage is near
+4.3V.
3
Measure pin 1 of U10.
a. Measured voltage is near +1V
b. Measured voltage is near 0V.
A-10
a. Check for defective U10 or
CR27.
b. Check for open Q10 or R55.
ADJUSTMENT AND CALIBRATION
c.
Current Limit Adjustment
+6V Supply. To adjust the current limit circuit in the +6V supply, proceed as follows:
a. Check the setting of the current limit by performing steps
(p) and (q) on page A-5. (Be sure to set the output voltage
to 6 volts.) If reducing the load resistance permits the current to exceed 2.9 A, stop, turn R6 slightly clockwise, and
repeat the test. If, instead, the current begins to fall before
it reaches 2.6 A, turn R6 slightly counter clockwise and
repeat the test.
b. Recheck the setting and readjust R6 until the test shows
that the current limit circuit begins to reduce the current
when a decreasing load resistance increases it to 2.75 A
± 5%.
Set the output voltage below 18V (ex, 15V), and adjust
R11 on the display board until front panel VOLTS display
reads exactly DVM value. Next, set the output voltage
above 20V (ex, 21V) and adjust R17 on the display board
until front panel VOLTS display reads exactly DVM value.
No other voltage output needs to be calibrated after
calibrating the voltmeter of +20V output.
Panel Ammeter. To calibrate ammeter for +20V output and 20V output, proceed as follows:
a. Connect RS between +20V output terminal and COM terminal and connect DVM across RS.
b. Push +20V meter switch and turn ±20V VOLTAGE control
fully clockwise.
c. Turn on the supply and adjust R5 on the display board
until front panel AMPS display reads exactly DVM value
divided by Rs.
d. To calibrate the ammeter for +6V output, select +6V
meter switch and turn +6V VOLTAGE control fully clockwise.
e. Adjust R61 on the main board until front panel AMPS display reads exactly DVM value divided by Rs.
Meter Calibration
Panel Voltmeters. To calibrate voltmeter, proceed as follows:
a. Connect DVM across +20V output terminal and COM terminal of the supply.
b. Turn on the supply.
A-11
REPLACEABLE PARTS
Table A-10. Reference Designators
INTRODUCTION
A
C
CR
DS
F
G
J
L
Q
R
S
T
TP
VR
U
W
This section contains information for ordering replacement
parts. Table A-12 lists parts by reference designators and provides the following information:
a.
b.
c.
d.
e.
f.
Reference designators. Refer to Table A-10.
Agilent Technologies Part Number.
Total quantity used in that assembly.
Description.
Manufacturer's supply code number. Refer to Table
A-11 for manufacturer's name and address.
Manufacturer's part number or type.
Mechanical and miscellaneous parts are not identified by reference designator.
Assembly
Capacitor
Diode
Signaling Device(light)
Fuse
Pulse Generator
Jack
Inductor
Transistor
Resistor
Switch
Transformer
Test Point
Zener Diode
Integrated Circuit
Wire
ORDERING INFORMATION
To order a replacement part, address order or inquiry to your
local Agilent Technologies sales office (see lists at rear of this
manual for addresses). Specify the following information for
each part: Model, complete serial number of the power supply; Agilent Technologies part number; circuit reference designator; and description.
Table A-11. Code List of Manufacturers
CODE
MANUFACTURER
ADDRESS
01295
Texas Instruments Inc, Semicon Comp Div.
Dallas, TX
14936
General Instruments Corp, Semicon Prod
Hicksville, N.Y.
27014
National Semiconductor Corporation
Santa Clara, CA
28480
Agilent Technologies
Palo Alto, CA
04713
Motorola Semiconductor Products
Phoenix, AZ
32997
Bourns Inc.
Riverside, CA
A-12
REFERENCE
DESIGNATION
PART
NUMBER
Q'TY
DESCRIPTION
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PART
NUMBER
Q'TY
DESCRIPTION
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MFR. CODE
MFR. P/N
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PART
NUMBER
Q'TY
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I
CERTIFICATION
Agilent Technologies certifies that this product met its published specifications at time of shipment from the factory. Agilent
Technologies further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology (formerly National Bureau of Standards), to the extent allowed by that organization's calibration facility,
and to the calibration facilities of other International Standards Organization members.
WARRANTY
This Agilent Technologies hardware product is warranted against defects in material and workmanship for a period of three
years from date of delivery. Agilent software and firmware products, which are designated by Agilent for use with a hardware
product and when properly installed on that hardware product, are warranted not to fail to execute their programming instructions due to defects in material and workmanship for a period of 90 days from date of delivery. During the warranty period,
either Agilent or Agilent Technologies will, at its option, either repair or replace products which prove to be defective. Agilent
does not warrant that operation the software, firmware, or hardware shall be uninterrupted or error free.
For warranty service, with the exception of warranty options, this product must be returned to a service facility designated by
Agilent. Return to Englewood Colorado Service Center for repair in United States(1-800-258-5165). Customer shall prepay
shipping charges by (and shall pay all duty and taxes) for products returned to Agilent for warranty service. Except for the
products returned to Customer from another country, Agilent shall pay for return of products to Customer.
Warranty services outside the country of initial purchase are included in Agilent's product price, only if Customer pays Agilent
international prices (defined as destination local currency price, or U.S. or Geneva Export price).
If Agilent is unable, within a reasonable time, to repair or replace any product to condition as warranted, the Customer shall
be entitled to a refund of the purchase price upon return of the product to Agilent.
The warranty period begins on the date of delivery or on the date of installation if installed by Agilent.
LIMITATION OF WARRANTY
The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by the Customer, Customer-supplied software or interfacing, unauthorized modification or misuse, operation outside of the environmental specifications for the product, or improper site preparation and maintenance. TO THE EXTENT ALLOWED BY LOCAL LAW, NO
OTHER WARRANTY IS EXPRESSED OR IMPLIED. AND AGILENT SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
For consumer transactions in Australia and New Zealand:
The warranty terms contained in this statement, except to the extent lawfully permitted, do not exclude, restrict or modify and
are in addition to the mandatory rights applicable to the sale of this product to you.
EXCLUSIVE REMEDIES
TO THE EXTENT ALLOWED BY LOCAL LAW, THE REMEDIES PROVIDED HEREIN ARE THE CUSTOMER'S SOLE AND
EXCLUSIVE REMEDIES. AGILENT SHALL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT, TORT, OR ANY OTHER LEGAL THEORY.
ASSISTANCE
The above statements apply only to the standard product warranty. Warranty options, extended support contacts, product
maintenance agreements and customer assistance agreements are also available. Contact your nearest Agilent Technologies Sales and Service office for further information on Agilent's full line of Support Programs.
DECLARATION OF CONFORMITY
according to ISO/IEC Guide 22 and EN 45014
Manufacturer’s Name:
Agilent Technologies, Inc.
Manufacturer’s Address:
345-15, Kasan-dong, Kumchon-ku,
Seoul 153-023 Korea
declares, that the products
Product Name:
DC Power Supply
Model Numbers:
E3630A
Product Options:
All Options
conforms to the following Product Specifications:
Safety:
IEC 1010-1:1990+A1:1992 / EN 61010-1:1993
EMC:
CISPR 11:1990 / EN 55011:1991 - Group 1 Class A1)
EN 50082-1:1992
IEC 801-2 : 1991 - 4KV CD, 8KV AD
IEC 801-3 : 1984 - 3V/m
IEC 801-4 : 1988 - 1kV Power Lines
0.5kV Signal Lines
Supplementary Information: The product herewith comply with the requirements of the
Low Voltage Directive 73/23/EEC and the EMC Directive 89/336/EEC and carry the “CE”
mark accordingly.
1)The
products was tested in a typical configuration with Agilent Technologies Test System.
Seoul, Korea
November 1, 1999
Quality Manager
European Contact for regulatory topics only: Hewlett-Packard GmbH, HQ-TRE, Herrenberger Strabe 110-140,
D-71034 Böbligen (FAX: +49-7031-143143).