Microtest 7700 User Manual

IMPULSE / SURGE TESTER
7700 / 7710 / 7720
User Manual
Issue B
3rd May 2006
Part Nº 9H7700
1–1
Contents
1.
SAFETY ............................................................................................................................1–4
1.1
1.2
1.3
1.4
2.
General ..........................................................................................................................1–4
AC Power Supply..........................................................................................................1–5
Adjustment, Maintenance and Repair ...........................................................................1–5
Static Electricity ............................................................................................................1–6
INTRODUCTION ............................................................................................................ 2-1
2.1 Package and Accessories............................................................................................... 2-1
2.1.1 7700 ....................................................................................................................... 2-1
2.1.2 7710 ....................................................................................................................... 2-1
2.1.3 7720 ....................................................................................................................... 2-1
3.
INSTALLATION ............................................................................................................. 3-1
3.1
3.2
3.3
3.4
4.
AC Line Connections .................................................................................................... 3-1
Location ........................................................................................................................ 3-1
Measurement Connections ............................................................................................ 3-1
Safety Interlock ............................................................................................................. 3-2
OPERATION.................................................................................................................... 4-1
4.1 The Front Panel ............................................................................................................. 4-1
4.2 The Rear Panel .............................................................................................................. 4-2
4.3 Product Identification .................................................................................................... 4-3
4.3.1 Ready State ............................................................................................................ 4-3
4.4 Keyboard ....................................................................................................................... 4-3
4.4.1 System Control ...................................................................................................... 4-3
4.4.2 Function ................................................................................................................. 4-3
4.4.3 Edit ........................................................................................................................ 4-3
4.4.4 Enter ...................................................................................................................... 4-4
4.4.5 Test ........................................................................................................................ 4-4
4.4.6 Screen Soft Keys ................................................................................................... 4-4
4.5 Function Menu .............................................................................................................. 4-4
4.5.1 Self–Test................................................................................................................ 4-4
4.5.2 SYS. INFO ............................................................................................................ 4-5
4.5.3 H/V CAL. and H/V TEST ..................................................................................... 4-5
4.6 System Setup Menu ...................................................................................................... 4-5
4.6.1 SYSTEM ............................................................................................................... 4-6
4.6.2 GRAPHICS ........................................................................................................... 4-8
4.6.3 DATE TIME ......................................................................................................... 4-9
4.6.4 PASSWORD ......................................................................................................... 4-9
4.7 Test Programs ............................................................................................................. 4-10
4.7.1 File Menu ............................................................................................................ 4-10
4.7.2 Filename Character Entry .................................................................................... 4-10
4.7.3 Creating a Test Program File............................................................................... 4-10
4.7.4 Edit an Existing Test Program............................................................................. 4-11
4.7.5 Deleting a Test Program ...................................................................................... 4-11
1–2
4.7.6
4.7.7
5.
Sorting ................................................................................................................. 4-11
View Mode .......................................................................................................... 4-12
TESTING A NEW COMPONENT ................................................................................ 5-1
5.1 Create a New Test Program File ................................................................................... 5-1
5.2 Test Voltage .................................................................................................................. 5-1
5.2.1 Example of Establishing the Test Voltage ............................................................ 5-1
5.3 Test Mode Menu ........................................................................................................... 5-1
5.3.1 Test Mode .............................................................................................................. 5-1
5.3.2 Dummy Pulse ........................................................................................................ 5-2
5.3.3 Testing Pulse ......................................................................................................... 5-2
5.4 Creating the Standard Waveform .................................................................................. 5-2
5.4.1 Safety Interlock ..................................................................................................... 5-2
5.4.2 Learning a Component .......................................................................................... 5-2
5.5 Selecting the Test Parameters ....................................................................................... 5-3
5.6 Setting the Test Parameters ........................................................................................... 5-3
5.6.1 Waveform Area Size Setup ................................................................................... 5-4
5.6.2 Differential Area Size Setup .................................................................................. 5-4
5.6.3 Flutter Value Setup ................................................................................................ 5-5
5.6.4 Waveform Comparison Setup ............................................................................... 5-6
5.6.5 Optimizing the Test Parameter Settings ................................................................ 5-7
6.
COMPONENT TESTING ............................................................................................... 6-1
6.1 Test Statistics ................................................................................................................ 6-2
7.
REMOTE CONTROL ..................................................................................................... 7-1
7.1 Serial Port ...................................................................................................................... 7-1
7.1.1 Protocol ................................................................................................................. 7-1
7.1.2 Serial Port Connections ......................................................................................... 7-1
7.1.3 REMOTE CONTROL SIGNAL ......................................................................... 7-1
7.1.4 Commands ............................................................................................................. 7-2
7.2 Handler Port .................................................................................................................. 7-4
7.2.1 Pin Assignment ...................................................................................................... 7-4
7.2.2 Port Timing............................................................................................................ 7-5
8.
THEORY OF OPERATION ........................................................................................... 8-1
8.1 Applied Pulse ................................................................................................................ 8-1
8.2 Why Use Impulse Testing? ........................................................................................... 8-1
9.
HIGH VOLTAGE CALIBRATION & TEST ............................................................... 9-1
9.1 High Voltage Calibration .............................................................................................. 9-1
9.2 High Voltage Test ......................................................................................................... 9-2
10. SPECIFICATION ......................................................................................................... 10–1
10.1
10.2
10.3
10.4
10.5
Measurement Ports ..................................................................................................... 10–1
Advanced Functions ................................................................................................... 10–1
Testing Functions ....................................................................................................... 10–1
Voltage Pulse ............................................................................................................. 10–1
Measuring Time ......................................................................................................... 10–1
1–3
10.6 Waveform Resolution .................................................................................................10–1
10.7 Display/Audio .............................................................................................................10–2
10.8 Interface ......................................................................................................................10–2
10.9 Memory .......................................................................................................................10–2
10.10 Power Supply .........................................................................................................10–2
10.11 Accessories .............................................................................................................10–2
10.12 Thermo/Humility ....................................................................................................10–2
10.13 Size .........................................................................................................................10–2
10.14 Weight ....................................................................................................................10–2
10.15 Options ...................................................................................................................10–3
11. MAINTENANCE, SUPPORT AND SERVICES ........................................................ 11-1
11.1 Guarantee .................................................................................................................... 11-1
11.2 Maintenance ................................................................................................................ 11-1
11.2.1 Cleaning .............................................................................................................. 11-1
11.2.2 Safety Checks ...................................................................................................... 11-1
11.3 Support and Service .................................................................................................... 11-2
1–4
1. Safety
1.1 General
This equipment has been designed to meet the requirements of EN61010-1 ‘Safety requirements
for electrical equipment for measurement, control & laboratory use’ and has left the factory in a
safe condition.
The following definitions in EN61010-1 are applicable:
OPERATOR
Person operating equipment for its intended purpose.
Note: The OPERATOR should have received training
appropriate for this purpose.
RESPONSIBLE BODY
Individual or group responsible for the use and maintenance
of equipment and for ensuring that operators are adequately
trained.
The RESPONSIBLE BODY must ensure that this equipment is only used in the manner
specified. If it is not used in such a manner, the protection provided by the equipment may be
impaired.
This product is not intended for use in atmospheres which are explosive, corrosive or adversely
polluted (e.g. containing conductive or excessive dust). It is not intended for use in safety
critical or medical applications.
The equipment can cause hazards if not used in accordance with these instructions. Read them
carefully and follow them in all respects.
Do not use the equipment if it is damaged. In such circumstances the equipment must be
made inoperative and secured against any unintentional operation.
MICROTEST ELECTRONICS and the associated sales organizations accept no
responsibility for personal or material damage, or for any consequential damage that
results from irresponsible or unspecified operation or misuse of this equipment.
1–5
1.2 AC Power Supply
Power cable and connector requirements vary between countries. Always use a cable that
conforms to local regulations, terminated in an IEC320 connector at the instrument end.
If it is necessary to fit a suitable AC power plug to the power cable, the user must observe the
following colour codes:
WIRE
EUROPEAN
N. AMERICAN
LIVE
BROWN
BLACK
NEUTRAL
BLUE
WHITE
GROUND
GREEN/YELLOW
GREEN
The user must also ensure that the protective ground lead would be the last to break should the
cable be subject to excessive strain.
If the plug is fused, a 3-amp fuse should be fitted.
If the power cable electrical connection to the AC power plug is through screw terminals then,
to ensure reliable connections, any solder tinning of the cable wires must be removed before
fitting the plug.
Before switching on the equipment, ensure that it is set to the voltage of the local AC power
supply.
WARNING!
Any interruption of the protective ground conductor inside or outside the equipment or
disconnection of the protective ground terminal is likely to make the equipment dangerous.
Intentional interruption is prohibited.
1.3 Adjustment, Maintenance and Repair
WARNING!
The equipment must be disconnected from all voltage sources before it is opened for any
adjustment, replacement, maintenance, or repair.
When the equipment is connected to the local AC power supply, internal terminals may be live
and the opening of the covers or removal of parts (except those to which access can be gained
by hand) is likely to expose live parts.
1–6
Capacitors inside the equipment may still be charged even if the equipment has been
disconnected from all voltage sources.
Any adjustment, maintenance, or repair of the opened equipment under voltage must be carried
out by a skilled person who is aware of the hazards involved.
Service personnel should be trained against unexpected hazards.
Ensure that only fuses with the required rated current and of the specified type are used for
replacement. The use of makeshift fuses and short-circuiting of fuse holders is prohibited.
1.4 Static Electricity
The unit supplied uses static-sensitive devices. Service personnel should be alerted to
components which require handling precautions to avoid damage by static electrical discharge.
Before handling circuit board assemblies containing these components, personnel should
observe the following precautions:
1) The work surface should be a conductive grounded mat.
2) Soldering irons must be grounded and tools must be in contact with a conductive surface to
ground when not in use.
3) Any person handling static-sensitive parts must wear a wrist strap which provides a leaky
path to ground, impedance not greater than 1MΩ.
4) Components or circuit board assemblies must be stored in or on conductive foam or mat
while work is in progress.
5) New components should be kept in the supplier’s packaging until required for use
2-1
2. Introduction
The 7700 series of Winding Testers provide a non-destructive way to test windings using a high
voltage pulse of between 500V and 10kV. By comparing the decay waveforms with a standard
winding, deviation in core material, number of turns, shorted turns, and insulation breakdown
can be identified.
The tester’s measurement, display and control facilities include:
•
memory for up to 200 standard windings
•
auto learn for standard windings
•
waveform area, differential area, flutter and waveform comparison
•
full statistics for each winding stored in memory
•
output of measurements and statistics to an Epson-compatible printer
•
built-in High Voltage calibration and test
•
the unit may be locked in test mode
2.1 Package and Accessories
2.1.1 7700
• 7700 Impulse Winding Tester
• 2 terminal
• Power cord and Connector
2.1.2 7710
• 7700 Impulse Winding Tester
• 2 terminal
• Power cord and Connector
2.1.3 7720
• 7720 Impulse Winding Tester
• 8 terminal
• Power cord and Connector
3-1
3. Installation
3.1 AC Line Connections
The unit is provided with a power cable capable of carrying the input current for both 115V and
230V operation. This cable should be connected via a suitable connector to the local AC power
supply. The colour code employed is as follows:
WIRE
EUROPEAN
N. AMERICAN
LIVE
BROWN
BLACK
NEUTRAL
BLUE
WHITE
GROUND
GREEN/YELLOW
GREEN
Figure 3-1 AC Power Cable Codes
The supply voltage setting can be checked by looking on the rear panel next to the power inlet
socket. Ensure that the unit is not connected to the power supply. Adjust the switch to read the
required voltage. No adjustment is required for variation of supply frequency.
Before connecting the AC power, read the precautions listed under section 1.2 AC Power
Supply.
The power switch is located on the left of the front panel.
The instrument is not suitable for battery operation.
3.2 Location
The instrument is intended for use on the bench. The power modules are fan cooled and care
must be taken not to restrict any of the air paths. Ensure that the unit is located in an area
appropriate for the hazardous voltages produced when testing components. See sections 3.3 and
3.4.
3.3 Measurement Connections
WARNING!
This equipment is intended for use by suitably trained and competent persons.
This product is capable of having hazardous voltages (up to 10kV) on its terminals in
normal use. Appropriate safety precautions should be taken.
This product can cause hazards if it is not used in accordance with these instructions.
Read them carefully and follow them in all respects. Double check connections to the unit
before use.
3-2
DO NOT USE THIS EQUIPMENT IF IT IS DAMAGED.
For maximum user safety, it recommended that a safety interlock is used.
3.4 Safety Interlock
WARNING!
HIGH VOLTAGE
This product is capable of having hazardous voltages (up to 10kV) on its terminals in
normal use. Appropriate safety precautions should be taken.
A high voltage pulse, or pulses, is applied during testing. The front panel High Voltage
(H.V.) LED will light whenever a high voltage pulse is applied to the component under test.
ENSURE THAT THE COMPONENT UNDER TEST AND TEST LEAD
TERMINATIONS CANNOT BE TOUCHED DURING THE TEST CYCLE.
The High Voltage (H.V.) output is inhibited until the safety interlock circuit is complete. The
terminal fixture for the winding under test should be placed within ahousing with an interlocked
door controlled by a circuit such as that shown in Figure 3-2.
Resistor R should be < 1kΩ.
Figure 3-2 Typical High.Voltage(H.V.) Interlock Fixture
When the fixture door is closed, and the micro switch therefore made, the High Voltage output
is activated via the relay. The relay also energizes an AC supply for a solenoid which can be
used to lock the door while the High Voltage output is on.
4-1
4. Operation
WARNING!
This equipment is intended for use by suitably trained and competent persons.
This product is capable of having hazardous voltages (up to 10kV) on its terminals in
normal use. Appropriate precautions should be taken for safety.
This product can cause hazards if it is not used in accordance with these instructions.
Read them carefully and follow them in all respects. Double check connections to the unit
before use.
READ SECTIONS 1 and 3 OF THIS MANUAL BEFORE USING THE 7720.
DO NOT USE THIS EQUIPMENT IF IT IS DAMAGED.
4.1 The Front Panel
(1)
(2) (3) (4) (5) (6) (7) (8)
Figure 4-1 770 / 77100 Front Panel
(9)
(10)
(1)
LCD Display
(2)
S1~S6 Soft Key
(3)
PASS & FAIL & H.V.Indicator
(4)
Edit Keys
(5)
(6)
Measure Key [TEST]
Function Keys
(7)
SysKey
(8)
Alpha-Numerical Keys
4-2
(9)
Power on/off switch
(10)
2 terminals high voltage testing connector
4.2 The Rear Panel
(1)
(2)
(3)
(4) (5)
Figure 4-2 Rear Panel
(1)
Serial Port (RS-232 Port)
(2)
Remote Control Port (Handler Port)
(3)
Printer Connection Port (Printer Port)
(4)
AC Input (230/115 VAC)
(5)
AC Input 115 or 230V Selection Switch
Note
Before connecting to the AC power source ensure that the selector switch (5) is set to the
correct voltage.
Ensure that the AC power source is always grounded.
4-3
4.3 Product Identification
A self testing program is executed when the instrument is initially switched on. At the end of
the self test the instrument displays the product identification graphic.
Figure 4-3 7720 Product Identification
4.3.1 Ready State
At the ready state the soft keys have the following capabilities:
„ S1
„ S2
„ S6
Brighten LCD backlight
Dim LCD backlight
System Information
4.4 Keyboard
4.4.1 System Control
„ [Func]
„ [Sys]
„ [Print]
Function Menu
System Setup Menu
Printing Function
4.4.2 Function
„
„
„
„
[File]
[Learn]
[Item]
[Stat]
File Management
Learn Waveform
Set Item
Statistic Report
4.4.3 Edit
„ Alpha Numeric Data
„ [BS] (Å)
0~1, A~Z, ．/
Back Space Key
4-4
„
„
„
„
Cursor [←] [→]
Cursor [↑] [↓]
Cursor [PgUp] [PgDn]
[Exit]
Navigation
Navigation
Navigation
Previous menu
4.4.4 Enter
Confirm Data Entered
4.4.5 Test
Start Device Testing
4.4.6 Screen Soft Keys
S1 to S6 are located at the right side of the display. Each key function is menu dependant.
4.5 Function Menu
Pressing the front panel Func key will display the FUNCTION menu. Select an option by
pressing the appropriate alphanumeric key or by using the and navigation keys to highlight
the option and then press Enter.
Figure 4-4 Function Menu
4.5.1 Self–Test
To run self test press Enter when the SELF–TEST option is highlighted. Use the
navigation keys to select the required option or press the alphanumeric 1 key.
and
The self-test will now run and display the test results. Figure 4-5 shows the SELF–TEST result
screen with all tests passed.
Press the SKIP soft key to disable any test. If the unit fails any stage of the self-test please
contact Microtest.
4-5
Figure 4-5 Self Test Menu
Use the EXIT soft key or the Exit key to return to the FUNCTION menu.
4.5.2 SYS. INFO
To display system information press Enter when the SYS. INFO. option is highlighted. Use the
and navigation keys to select the required option or press the alphanumeric 2 key.
The system information will now be displayed on the screen and includes file space available,
software and hardware versions. Some of this information may be requested if Microtest is
contacted for assistance with the unit.
Figure 4-6 System Information Menu
Press the EXIT soft key or the Exit key to leave the SYSTEM INFO screen.
4.5.3 H/V CAL. and H/V TEST
Refer to Chapter 9 for High Voltage Calibration and Test procedures.
4.6 System Setup Menu
Pressing the front panel Sys key will display the SYSTEM SETUP menu. Select an option by
pressing the appropriate alphanumeric key or by using the and navigation keys, to highlight
the option and then press Enter.
4-6
Figure 4-7 System Set-up Menu
4.6.1 SYSTEM
To display the SYSTEM SETUP sub-menu press Enter when the SYSTEM option is
and
navigation keys to select the required option or press the
highlighted. Use the
alphanumeric 1 key.
Figure 4-8 System Set-up Sub-Menu
TESTER ID No.
The TESTER ID No. can be changed to identify the unit. This is useful when analysing results
from more than one tester. To change the number:
1) Move the highlight to the existing number with the
and
navigation keys.
2) Type in the new number; up to three digits may be entered.
KEY LOCK
Prevents unauthorized users accessing the test set-up. A password must be entered when
switching the key lock on or off. See section 4.6.4 for details on how to change the KEY
LOCK password.
To change the key lock state:
4-7
1) Move the highlight to the KEY LOCK option with the
and
navigation keys.
or
navigation keys, or the PROG soft key: the CHECK
2) Press either of the
PASSWORD box, shown below, will be displayed.
3) Enter the correct password, then press Enter. The key lock will now be set to the
opposite state.
Figure 4-9 Key Lock Password
KEY STROKE SOUND
When set to ON the KEY STROKE SOUND option enables a beep for each key press. To
change the KEY STROKE SOUND state:
1) Move the highlight to the KEY STROKE SOUND option with the
keys.
2) Press either the
or
and
navigation
navigation keys, or PROG soft key to set the opposite state.
LCD CONTRAST
The LCD CONTRAST is set by highlighting the option with the and navigation keys. Use
the
or PROG soft key to lighten the screen. or
to darken it. Range: 1 – 8. Default: 5.
TEST ALARM
The TEST ALARM is set by highlighting the option with the and navigation keys. Use the
and
navigation keys or the PROG soft key to change the setting. There are four settings
as shown in Figure 4-10. The alarm will sound when the corresponding state is indicated during
a Test.
Setting
Alarm
NO
NO test alarms
ALL
test alarms for both PASS and FAIL
PASS
test alarm for PASS only
FAIL
test alarm for FAIL only
Figure 4-10 Test Alarm Options
4-8
4.6.2 GRAPHICS
To display the GRAPHICS SETUP menu press Enter when the GRAPHICS option is
highlighted. Use the
and
navigation keys to select the required option or press the
alphanumeric 2 key.
Figure 4-11 Graphics Set-Up Menu
STANDARD WAVE
The STANDARD WAVE can be shown on the test screen in either a line or dot format, or can
be turned off.
To change the STANDARD WAVE setting:
1) Move the highlight to the STANDARD WAVE option with the
keys.
2) Press either the
or
and
navigation
navigation keys, or the PROG soft key to change the setting.
D.U.T. WAVE
The D.U.T. WAVE can be shown on the test screen in either a line or dot format. To change the
D.U.T. WAVE setting:
1) Move the highlight to the D.U.T. WAVE option with the
2) Press either the
or
and
navigation keys.
navigation keys, or the PROG soft key to change the setting.
COMPARISON MASK
If COMPARISON MASK is set ON and WAVEFORM COMPARISON is selected (see
section 5.6.4), the upper and lower limit waveform will be displayed.
To change the COMPARISON MASK setting:
1) Move the highlight to the COMPARISON MASK option with the
keys.
2) Press either the
or
CENTRE LINE and GRID
and
navigation
navigation keys, or the PROG soft key to change the setting.
4-9
The CENTRE LINE and GRID, shown in the TEST display, can be turned ON or OFF as
follows:
1) Move the highlight to the required option with the
2) Press either the
or
and
navigation keys.
navigation keys, or the PROG soft key to change the setting.
4.6.3 DATE TIME
To display the SET TIME menu press Enter when the DATE TIME option is highlighted (use
the and navigation keys to select the required option), or press the alphanumeric 3 key.
Figure 4-12 Set Time Menu
The date and time may be set using the navigation and alphanumeric keys. Once the correct date
and time is entered, press the SET and EXIT soft keys to return to the SYSTEM SETUP menu.
4.6.4 PASSWORD
To display the CHECK/SET PASSWORD text box press Enter when the PASSWORD option
is highlighted. Use the and navigation keys to select the required option or press the
alphanumeric 4 key.
Figure 4-13 Key Lock Password Entry
This option modifies the password for the KEY LOCK function and system password. The
factory default password is 7720.
To change the password:1) Enter the old password and then press the front panel Enter key.
4-10
2) Enter the new password and then press the front panel Enter key.
3) Re-enter the new password again and press the front panel Enter key.
4.7 Test Programs
Each component to be tested requires a test file to be created which includes the test parameter
settings and the learnt waveform from a known good working ‘golden’ component. The learnt
(standard) waveform provides the comparison data to which subsequent components are
compared.
Test files may be uploaded to a PC or retrieved using the serial interface.
4.7.1 File Menu
To enter the FILE menu press the front panel File short-cut key.
Figure 4-14 File Menu
4.7.2 Filename Character Entry
Use the navigation the
or
navigation keys to select the position of the character to be
entered and the numeric keypad to enter the number or character.
For example the key which is used to enter the number 1 is also used to enter A, B or C.
Continue to operate the key until the desired character is displayed and then press the
navigation key to enter the next character.
Once all the characters are entered use the Enter key to confirm the file name.
4.7.3 Creating a Test Program File
1) Press the NEW soft key.
2) Enter a file name of up to eight characters in the CREATE NEW FILE box using the
or
navigation keys. Press Enter to confirm the file
alphanumeric keys and the
name.
4-11
Figure 4-15 Creating a New File
The unit is now ready for the standard waveform to be learnt and the Test Parameters to be
entered. See Chapter 5 for more information.
4.7.4 Edit an Existing Test Program
Enables modification of existing test program parameters or to learn a known good working
‘golden’ sample component.
1) Enter the FILE menu by pressing the front panel File key.
2) Use the
and
navigation keys to highlight the required file.
3) Press the EDIT soft key and the Test Parameter menu will be displayed.
4.7.5 Deleting a Test Program
To delete a file:
1) Use the
and
navigation keys to highlight the required file.
2) Press the DEL soft key: the DELETE FILE box, shown below, will be displayed.
3) Press the front panel Enter key to confirm the file deletion, or press Exit to cancel the
file deletion and return to the FILE menu.
Figure 4-16 Delete File Menu
4.7.6 Sorting
While in the FILE menu, the files can be sorting by four different criteria by repeatedly pressing
the SORT soft key. The sort options are:Ascending by name or date
Descending by name or date
4-12
4.7.7 View Mode
The date and time file information may be displayed or hidden using the VIEW MODE soft key.
Figure 4-17 View Mode
5-1
5. Testing a New Component
To test a new component a standard waveform has to be learnt for each test step from a known
good ‘golden’ sample and then the optimum test parameter settings established by testing a
quantity, of golden sample components.
The test parameters define the expected variation of component characteristics.
5.1 Create a New Test Program File
1) Enter the FILE menu by pressing the front panel File short-cut key.
2) Create a new file as described in section 4.7.3
3) The instrument will then enter the ‘Learn’ mode screen.
5.2 Test Voltage
The applied test voltage pulse must be set to a level that will ensure that faulty components are
detected, yet set not too high to cause component damage.
ALWAYS CONSULT THE COMPONENT TEST SPECIFICATION PRIOR TO SETTING
THE TEST VOLTAGE LEVEL.
1) Highlight the voltage level using the
and
navigation keys.
2) Enter the test level using the front panel keypad.
3) Press Enter to confirm.
5.2.1 Example of Establishing the Test Voltage
A coil with a nominal working voltage of 220V used a test voltage of 1.5KV which was derived
from the formula 220 x 1.414 x 5. The applied voltage was well within the maximum voltage
level that could be applied to the component yet enabled manufacturing faults to be identified.
5.3 Test Mode Menu
Enter the Test Mode menu by selecting ‘Mode’ from the Learn menu. Use the
navigation keys to select the mode parameter to be modified.
and
The EXIT soft key returns to the LEARN menu.
5.3.1 Test Mode
The Test Mode menu is used to modify the pulse applied dependant on the characteristics of the
component to be tested. The options ‘NORMAL’, ‘LOW Q’, ‘LOW L’ and ‘LOW LQ’ may be
set using the PROG soft key.
The majority of components will use the ‘NORMAL’ setting and this is recommended for
learning a component for the first time.
5-2
5.3.2 Dummy Pulse
The Dummy Pulse facility pre-magnetises a component and may be useful where a residual
magnetic field is present prior to applying the test pulse.
5.3.3 Testing Pulse
The alphanumeric keypad is used to set the number of Pulses generated when testing a
component.
5.4 Creating the Standard Waveform
WARNING!
HIGH VOLTAGE
This product is capable of having hazardous voltages (up to 10kV) on its terminals in
normal use. Appropriate safety precautions should be taken.
A high voltage pulse, or pulses, is applied during testing. The front panel High Voltage
(H.V.) LED will light whenever a high voltage pulse is applied to the component under test.
ENSURE THAT THE COMPONENT UNDER TEST AND TEST LEAD
TERMINATIONS CANNOT BE TOUCHED DURING THE TEST CYCLE.
The unit tests components by comparing each test result standard waveform(s) learned from a
known good ‘golden’ sample..
5.4.1 Safety Interlock
The High Voltage (H.V.) output is inhibited until the safety interlock circuit is complete. Place a
‘golden’ sample in the safety enclosure and connect the instrument to the component/enclosure.
Close the safety door to complete the Safety Interlock circuit. For more information see section
3.4.
5.4.2 Learning a Component
1) Press the LEARN/TRIG soft key or the front panel Learn key: the component will be
tested and its waveform will be displayed. The front panel H.V. LED (High Voltage)
will illuminate when the high voltage pulse is applied to the component.
2) Use the zoom in and zoom out soft keys if the waveform displayed is not as required.
The waveform displayed will vary dependant upon the component being learnt. Use the Zoom
soft keys to ensure that at least one complete cycle of the waveform is displayed. After each
change of waveform the unit will prompt the user to press the TRIG key to test the standard
component at the new settings.
5-3
5.5 Selecting the Test Parameters
Figure 5-1 7700 / 7710 2 Port Test Parameter Menu
Figure 5-2 7720 8 Port Test Parameter Menu
Press the front panel Para key: the TEST PARAMETER menu will be displayed.
For each step highlight the individual test parameters required to be measured using the
and navigation keys. Use either the ON or OFF soft key to select or remove the test.
The 7720 instruments with more than two channels have a multi step capability allowing the
test channels to be specified for each step. For enhanced fault finding ability consider using
for example 1 – 2 for step 1 followed by 2 – 1 for step 2.
Once the test parameters and channels, if applicable, have been chosen each parameter must
be programmed by highlighting it with the and navigation keys and pressing the SET–
UP soft key or by using the Para keyboard key.
5.6 Setting the Test Parameters
The Test Parameters define the expected variation of component characteristics compared to a
stored learnt standard test waveform obtained from a known good ‘golden’ sample component.
Any variation of waveform exceeding the entered parameters will fail the component under test.
If available use a ‘golden’ component sample, that was not used to produce the learnt standard
waveform, to establish the initial parameter limits
When all the changes have been made save the settings by pressing the front panel TEST key.
5-4
Establishing the optimum parameter settings will involve testing a quantity of ‘golden’ samples
and adjusting the tolerance levels as required. Use the Para key or the EDIT soft key from the
FILE menu.
5.6.1 Waveform Area Size Setup
The WAVEFORM AREA SIZE test looks for a change in the area under the waveform but
does not take into account any distortion or movement of the waveform.
With the WAVEFORM AREA SIZE test turned ON and selected with the cursor, press the
SET–UP soft key: the WAVEFORM AREA SIZE set-up display (Figure 5-3 left) will be
shown.
The TOLERANCE is set by typing in the required value with the alphanumeric keypad,
followed by Enter.
The TEST RANGE (right) is set with the T1 and T2 soft keys.
Pressing the PRE–TEST soft key with a component connected to the unit’s test connectors will
show the component characteristics superimposed on the standard waveform to allow an instant
comparison. Adjustments can then be made to the WAVEFORM AREA SIZE set-up if
required. See sections 3.3 and 3.4 for important safety information.
Press the EXIT soft key or the front panel Exit key to return to the TEST PARAMETER menu.
Figure 5-3 Waveform Area Size
5.6.2 Differential Area Size Setup
The DIFFERENTIAL AREA SIZE test looks for any movement or distortion outside the
waveform but does not take into account any change in the area of the waveform.
With the DIFFERENTIAL AREA SIZE test turned ON and selected with the cursor, press the
SET–UP soft key: the DIFFERENTIAL AREA SIZE set-up display (Figure 5-4) will be
shown.
The TOLERANCE is set by typing in the required value with the alphanumeric keypad,
followed by Enter.
The TEST RANGE is set with the T1 and T2 soft keys.
5-5
Pressing the PRE–TEST soft key with a component connected to the unit’s test connectors will
show the component characteristics superimposed on the standard waveform to allow an instant
comparison. Adjustments can then be made to the DIFFERENTIAL AREA SIZE set-up if
required. See sections 3.3 and 3.4 for important safety information.
Press the EXIT soft key or the front panel Exit key to return to the TEST PARAMETER menu.
Figure 5-4 Differential Area Size
5.6.3 Flutter Value Setup
The FLUTTER VALUE calculates the number of level differences (corona discharges) from
one waveform point to the next on a voltage waveform.
With the FLUTTER VALUE test turned ON and selected with the cursor, press the SET–UP
soft key: the FLUTTER VALUE set-up display will be shown.
The corona COUNT value is set by typing in the required number with the alphanumeric
keypad, followed by Enter.
The TEST RANGE is set with the T1 and T2 soft keys.
Pressing the PRE–TEST soft key with a component connected to the unit’s test connectors will
show the component characteristics superimposed on the standard waveform to allow an instant
comparison. Adjustments can then be made to the FLUTTER VALUE set-up if required. See
sections 3.3 and 3.4 for important safety information.
Press the EXIT soft key or the front panel Exit key to return to the TEST PARAMETER menu.
5-6
Figure 5-5 Flutter Value
5.6.4 Waveform Comparison Setup
WAVEFORM COMPARISON looks for a change in the waveform voltage or frequency.
With the WAVEFORM COMPARISON test turned ON and selected with the cursor, press
the SET–UP soft key: the WAVEFORM COMPARISON set-up display (Figure 5-6) will be
shown.
The TIME TOL and VOLTAGE TOL values are set by typing in the required value with the
alphanumeric keypad, followed by Enter. Use the
and
keys to navigate between the two
settings.
Pressing the PRE–TEST soft key with a component connected to the unit’s test connectors will
show the component characteristics superimposed on the standard waveform to allow an instant
waveform comparison. To pass this test the waveform must be between the upper and lower
waveforms displayed. See sections 3.3 and 3.4 for important safety information.
The TEST RANGE is set with the T1 and T2 soft keys.
Press the EXIT soft key or the front panel Exit key to return to the TEST PARAMETER menu.
Figure 5-6 Waveform Comparison
5-7
5.6.5 Optimizing the Test Parameter Settings
To optimize the parameter settings a quantity of known good working golden samples will be
required. It is recommended that at least five samples are used during optimization.
Test each sample and note the test differences compared to the learnt waveform.
Example Test Parameter Values
The final Test Parameter settings used are dependant on component design and manufacturing
quality.
As a guide it is recommended that initially the Test Parameter tolerance be set to three times the
average percentage variation of the ‘golden’ samples tested. Where a count is specified set the
count to be the count plus 10%.
To modify the settings select the Para key or use the EDIT key in the File menu. Once
parameter entry has been completed return to the file menu and select TEST.
6-1
6. Component Testing
WARNING!
HIGH VOLTAGE
This product is capable of having hazardous voltages (up to 10kV) on its terminals in
normal use. Appropriate safety precautions should be taken.
A high voltage pulse, or pulses, is applied during testing. The front panel High Voltage
(H.V.) LED will light whenever a high voltage pulse is applied to the component under test.
ENSURE THAT THE COMPONENT UNDER TEST AND TEST LEAD
TERMINATIONS CANNOT BE TOUCHED DURING THE TEST CYCLE.
Prior to production testing a component a test file must be created for that component type, the
standard waveform ‘learnt’ from a ‘Golden’ sample, and Test Parameters set and optimized. See
Chapter 5 for more information.
1) Press the front panel File key and highlight the file required with the
navigation keys.
and
2) Press the TEST soft key and the standard component waveform will be displayed.
3) Connect the component to be tested using an enclosure incorporating a safety interlock
circuit. See sections 3.3 and 3.4 for important safety information.
4) Press the front panel TEST key.
The front panel H.V. LED (High Voltage) will illuminate when the high voltage pulse is
applied to the component.
When the test is complete PASS or FAIL is displayed on the screen together with the test
results. The component waveform will be displayed, superimposed on the standard
waveform. The PASS/FAIL front panel LEDs will also indicate the result of the test.
Figure 6-1 Test Result
6-2
6.1 Test Statistics
Pressing the STAT soft key or the front panel Stat key will show the test statistics of the
currently loaded file. An example is shown below.
Figure 6-2 Test Statistics
Press the QTY. RATE soft key to toggle between absolute and percentage statistics.
To clear the data press the CLR soft key.
The front panel Print key prints the screen display to an Epson-compatible printer.
Press the EXIT soft key or the front panel Exit key to return to the Test mode.
7-1
7. Remote Control
7.1 Serial Port
7.1.1 Protocol
Baud rate:
9600bps
Character length: 8bits
Stop bit:
1bit
Parity:
Non-parity
Character:
ASCII character
7.1.2 Serial Port Connections
Function
7220
Controller
RxD
Pin 2
Pin 3
TxD
Pin 3
Pin 2
GND
Pin 5
Pin 5
RTS
Pin 7
Pin 8
CTS
Pin 8
Pin 7
7.1.3 REMOTE CONTROL SIGNAL
PIN#
NAME FUNC
1
CTL1
PASS
2
CTL2
FAIL
3
CTL3
H.V. ON
4
CTL4
TEST
5
CTL5
WIND 1
6
CTL6
WIND 2
7
CTL7
WIND 3
8
CTL8
WIND 4
9
V1
+12V
10 IN1
SW1
11
IN2
SW2
12
RST
RESET
7-2
13
V2
+5V
14
V3
+12V
15
GND
GROUND
7.1.4 Commands
Commands are terminated by LF (line feed, ASCII code 10 (decimal), 0xA (hexadecimal); only
the LF is effective as the terminator.
Download (D)
D – reference file is sent from the computer to 7720
4608 bytes in length 4, 6 or 8 port instruments
512 bytes in length 2 port instruments
The command ‘D’ should be sent followed by LF. A delay of 100ms may be required before the
file data is sent.
Upload (U)
U – reference file is sent from 7720 to the computer
4608 bytes in length 4, 6 or 8 port instruments
521 bytes in length 2 port instrument
7-3
System Key (Kn)
Kn - simulates the pressing of a specified front-panel key. User must make sure the 7720 is in
the desired state before executing this command and essential delay time generated to ensure the
key command is executed without loss of information prior to sending a further command.
Where n = 1
Number key 1
2
Number key 2
3
Number key 3
4
Number key 4
5
Number key 5
6
Number key 6
7
Number key 7
8
Number key 8
9
Number key 9
0
Number key 0
.
Dot key
B
Backspace
U
Up arrow
D
Down arrow
l
Left arrow
R
Right arrow
E
Enter
T
Test
E
Exit
N
Func
Y
Sys
L
Learn
P
Para
a
Function key 1
b
Function key 2
c
Function key 3
d
Function key 4
e
Function key 5
f
Function key 6
7-4
Test Step Number (S?)
Returns the number of the step that is currently being edited.
Trigger (T)
Trigger the 7720 and query the test result with waveform data returned.
Trigger (t)
Trigger the 7720 and query the test result without waveform data being returned.
7.2 Handler Port
7.2.1 Pin Assignment
A test is performed whenever IPC∅ and GND are shorted.
Pin
Signal
Pin
Signal
1
CTL0
9
+12V
2
CTL1
10
IPC0
3
CTL2
11
IPC1
4
CTL3
12
RESET
5
CTL4
13
+5V
6
CTL5
14
+12V
7
CTL6
15
GND
8
CTL7
PIN
NAME
Description
1
CTRL1
PASS, to indicate the pass test result
2
CTRL2
FAIL, to indicate the fail test result
3
CTRL3
H.V. ON, to indicate the high voltage is applied
4
CTRL4
Testing, to indicate the test is in progress
5
CTRL5
Reserved
6
CTRL6
Reserved
7
CTRL7
Reserved
8
CTRL8
Reserved
9
+12V
12V DC output for user applications
10
IPC0
Test is performed whenever IPC∅ and GND are shorted.
11
IPC1
Reserved
7-5
12
RESET
System is reset whenever RESET and GND are shorted.
13
+5V
5V DC output for user applications
14
+12V
same as pin 9
15
GND
Ground
CTRL0 – CTRL3 are photo-coupled, they are grounded when active, floating when inactive.
7.2.2 Port Timing
1. Trigger signal duration greater than 10mS.
2. PASS or FAIL is issued when all tests are finished and is not cleared until the next trigger
pulse is received.
8-1
8. Theory of Operation
8.1 Applied Pulse
When a short high voltage pulse is applied to a perfect unloaded inductor a sine wave would be
seen that continued to infinity without changing amplitude.
However, the perfect inductor does not exist and making a measurement will always apply a
small load to the device under test. So what is actually seen is a sine wave with a decaying
amplitude.
Figure 8-1 Theory of Operation
The waveform decay is related to the Q-factor of the coil: the higher the Q, the slower the rate
of decay. The frequency of the waveform is related to the inductance and stray capacitance of
the coil.
The Impulse Winding Tester 7720 allows the user to store a standard waveform
produced from a known good ‘golden’ component sample. It will then compare this
waveform against the waveform of the device under test.
8.2 Why Use Impulse Testing?
Impulse testing characterizes a winding in a way not possible on a conventional LCR meter.
The short high voltage pulse will cause no damage to the device under test.
Comparing the waveform from a good device to that of the device under test will show
differences in the number of turns, changes in the core material, shorted turns and corona
discharge (damage to the winding).
The differences are shown as a waveform that decays at a different rate, which would be
indicated by the area under the curve. A waveform that is out of phase with the standard
waveform would be indicated by differential area size, or a combination of both indicated by
waveform comparison.
Corona discharge, indicated by a spike on the waveform, is normally present when a high
voltage charge is applied across a wire (winding) that has some damage to the insulation.
8-2
Figure 8-2 Corona Discharge
9-1
9. High Voltage Calibration & Test
WARNING!
HIGH VOLTAGE
This product is capable of having hazardous voltages (up to 10kV) on its terminals in
normal use. Appropriate safety precautions should be taken.
High voltages are applied during calibration. Double check connections before calibration
and test.
DO NOT TOUCH TEST LEAD OR VOLTAGE METER TERMINATIONS WHILE
CALIBRATING THE INSTRUMENT.
CAUTION!
If the following procedure is not carried out correctly the output voltage may be set
incorrectly, which could cause incorrect reading and/or damage to the device under test.
Consult Microtest, before calibration, if the unit is suspected of being faulty.
9.1 High Voltage Calibration
To calibrate each output range voltage levels, select the FUNCTION menu using the Func key.
Select High Voltage Calibration by pressing Enter when the H/V CAL. option is highlighted.
Use the and navigation keys to select the required option or press the alphanumeric 3 key.
The 7720 will require a password before the calibration values can be adjusted.
To change voltage levels use the and navigation keys to select each nominal voltage level
in turn. Once selected, the actual output will be displayed in the READING column. To adjust
the voltage use the UP and DOWN soft keys until the value displayed is as close as possible to
the nominal voltage selected.
Repeat this process for each nominal voltage level. When completed, press the DONE soft key.
If the EXIT is pressed any changes to the nominal voltage levels will not be saved.
Note
The H.V. output may be monitored using an external High Voltage meter (input resistance
≥1GΩ). Connect the meter probe to “H.V. CAL.” and “RETURN” to measure the high voltage.
9-2
9.2 High Voltage Test
To check the output voltage at each available voltage step, select the FUNCTION menu using
the Func key. Select the high voltage test by pressing Enter when the H/V TEST option is
and
navigation keys to select the required option or press the
highlighted. Use the
alphanumeric 4 key.
Turn the voltage on using the ON soft key: the unit will display the output voltage. Use the UP
or DOWN soft keys to step through the voltages monitoring the displayed reading.
Note
The H.V. output may be monitored using an external High Voltage meter (input resistance
≥1GΩ). Connect the meter probe to “H.V. CAL.” and “RETURN” to measure the high voltage.
10–1
10. Specification
10.1 Measurement Ports
Two – 7700/7710
Eight – 7720
10.2 Advanced Functions
5000V testing voltage (7700/7720)
10000V testing voltage (7710)
Auto Learning / Auto Testing
Test Result Statistics and Analysis
System Self Diagnostic
Password Management
10.3 Testing Functions
Waveform Area
Waveform Area Changes
Corona -High Voltage Arching (Flutter)
Waveform Comparison
10.4 Voltage Pulse
7700/7720 Programmable 500~5000V ±2%
7710 Programmable 500~10000V ±2%
10.5 Measuring Time
50ms
10.6 Waveform Resolution
High Speed A/D Conversion
Maximum Sampling Time：10ns
Maximum Sample size of 8192 Bytes
10–2
10.7 Display/Audio
320 x 240 LCD Display
Pass/Fail Red-Green LED and on Screen
Action Feedback Beep
10.8 Interface
RS-232
Printer Port
Remote Port
GPIB Port (Reserved)
10.9 Memory
Flash Memory
Store up to 100 sets of Wave Information
10.10 Power Supply
115/230 Vac Switchable ±10% 60/50Hz
10.11 Accessories
2 connection cables (7700/7710)
8 connection cables (7720)
Remote Connection Cable
Power Cord
User’s Manual
10.12 Thermo/Humility
00C ~ 400C
RH≦75%
10.13 Size
440mm x 145mm x 540mm (W x H x D)
10.14 Weight
About 13Kgs (accessories not included)
10–3
10.15 Options
/M2
Stores 200 sets of Waveforms
/M4
Stores 400 sets of Waveforms
11-1
11. Maintenance, Support and Services
11.1 Guarantee
The equipment supplied by is guaranteed against defective material and faulty manufacture for a
period of twelve months from the date of dispatch. In the case of materials or components
employed in the equipment but not manufactured by us, we allow the customer the period of any
guarantee extended to us.
The equipment has been carefully inspected and submitted to comprehensive tests at the factory
prior to dispatch. If, within the guarantee period, any defect is discovered in the equipment in
respect of material or workmanship and reasonably within our control, we undertake to make good
the defect at our own expense subject to our standard conditions of sale. In exceptional
circumstances and at the discretion of the service manager, a charge for labour and carriage costs
incurred may be made.
Our responsibility is in all cases limited to the cost of making good the defect in the equipment
itself. The guarantee does not extend to third parties, nor does it apply to defects caused by
abnormal conditions of working, accident, misuse, neglect or wear and tear.
11.2 Maintenance
11.2.1 Cleaning
The body of the equipment can be cleaned with a damp lint-free cloth. Should it be required, weak
detergents can be used. No water must enter the equipment. Do not attempt to wash down internal
parts.
11.2.2 Safety Checks
Each year the equipment should be given a simple safety check.
Equipment required
25A ground bond tester (e.g. Megger PAT 2)
Insulation tester @ 500V DC (e.g. Megger BM 7)
Tests
1) DISCONNECT THE INSTRUMENT FROM THE AC POWER SUPPLY!
2) Inspect the unit and associated wiring for damage e.g. dents or missing parts which might
impair the safety or function of the equipment. Look for any signs of overheating or
evidence that objects might have entered the unit.
3) Ground Bond: Ensure that 25A DC can flow from exposed metal parts of the unit (not
BNC connector outers) to ground with an impedance of less than 100mΩ.
4) Insulation Test: Connect the Live and Neutral of the power cable together and test the
insulation between this point and the ground at 500V DC. Readings greater than 1MΩ are
acceptable.
11-2
11.3 Support and Service
In the event of difficulty, or apparent circuit malfunction, it is advisable to contact the service
department or your local sales engineer or agent (if overseas) for advice before attempting repairs.
For repairs and recalibration it is recommended that the complete instrument be returned to one of
the following:
Microtest
14F-6, No.79, Hsin Tai Wu Road, Sec. 1,
Hsi-chih, Taipei 221, Taiwan, R.O.C.
Tel: +886-2-2698-3877
Fax: +886-2-2698-4089
Email: [email protected]
When returning the instrument please ensure adequate care is taken with packing and
arrange insurance cover against transit damage or loss. If possible re-use the original
packing box.