Larkin M5500 User manual

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Larkin Power Components, Inc.
P.O. Box 14667, Spokane, WA 99214-0667, U.S.A.
Phone: [phone] Fax: [phone]
E-mail : [e-mail] Web page : www.larkinpower.com
Power Semiconductor Tester
M5500
User’s Guide

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Table of Content
SPECIFICATIONS 3
TESTING POWER SEMICONDUCTORS 4
CLAMPING DEVICE FOR PRESSURE PACK DEVICES 5
CONNECTIONS ON DIODES AND THYRISTORS 5
OVERVIEW OF TESTING PROCEDURES 6
TESTING SET-UP AND PROCEDURES
Pressure Pack SCRs (Thyristors) 8
Pressure Pack Diodes 9
Stud-mounted diodes 9
GTOs (Gate Turn-off Thyristor) 10
Power Modules 11
Transistor Modules (IGBTs and DARLINGTONs) 12
Diode Modules for Rotating Rectifiers 13
USING THE OSCILLOSCOPE OPTION 14

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SPECIFICATIONS
Electrical specifications apply for an operating temperature range of 15oF to 120oF
(-10oC to 50oC), relative humidity up to 80%.
Input Voltage of M3K-120V Test Set 100-125V, 50-60Hz, 2A
Input Voltage of M3K-240V Test Set 220-245V, 50-60Hz, 2A
High Voltage Mode (PRV/PFV)
Peak Reverse and Forward Voltage 0 - 5800 VPK
Peak Leakage Current @ 3 Mohm 1.83 mA
Short Circuit Current 10 mA
Test Duration max. 15 seconds
Gate Mode
Gate Voltage 0 - 20 VDC, 10 ohm source impedance
Anode Voltage 14 - 18 V, 10 ohm, 1/2 sine wave
Panel Meters
PRV/PFV Mode
Peak Anode Voltage 6400 VPK
Peak Leakage Current 19.99 mA
Gate Mode
Gate Voltage 19.99VDC
Gate Current 1999 mA
Oscilloscope Input
PRV/PFV Mode
X- axis (voltage) sensitivity 1.0 V/div=1000 V/div
Y-axis (current) sensitivity 1.0 V/div=10 mA/div
Gate Mode (Anode Voltage/Current Curve)
X- axis (voltage) sensitivity 2.0 V/div=10 V/div (Anode Voltage)
Y-axis (current) sensitivity 2.0 V/div=1 A/div (Anode Current)
Case Dimensions (L x W x D) 19" x 14" x 7" / 49cm x 36cm x 18cm
Weight 20 Lbs. / 9.072 kg
Test Standard JEDEC JC22, RS397

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* * * CAUTION * * * *
The part to be tested must be Isolated & De-energized! Connecting the tester to live equipment
will damage the tester.
This equipment operates at voltages as high as 6400V.
Under no circumstances should the equipment EVER be operated without using the 3 wire line
cord, plugged into a properly grounded outlet.
The equipment must be operated in strict accordance with the operating instructions. The pro-
cedures are set up so that the voltage is turned to zero before a test is started.
Do not touch, or allow anyone else to touch, the test leads or the device under test while the
TEST BUTTON IS PRESSED!
THE “ART” OF TESTING POWER SEMICONDUCTORS
Manufacturers of power semiconductors follow the test methods outlined in the JEDEC sub-
committee JC22 for SCRs and Diodes. The standard for SCRs is RS397. One of the most im-
portant conditions of this test is that the rated voltage MUST NOT be exceeded.
An ideal SCR or Diode can have voltage applied until the device reaches avalanche voltage. In
practice, many devices have soft breakdown, “punch through” or surface breakdown before the
rated leakage current is reached. For these devices, exceeding the rated voltage established by
the manufacturer may result in instant failure or in down grading of the blocking characteristics.
Large devices have round silicon chips which have been beveled and contoured to reduce the
voltage stress at the device junctions at the end of the chip. These devices generally reach ava-
lanche voltage or “punch through” before breakdown occurs at the surface.
Small devices on the other hand are made from square chips. These devices are not protected by
the above methods and many will break down at the edge of the chip before avalanche voltage
is reached. This form of breakdown is almost always “fatal”
SUMMARY
DON’T use an OHMMETER
DON’T use a HI POT tester
DO use a tester that conforms to the JEDEC standards
NEVER exceed the manufacturers blocking voltage rating!
NEVER exceed the manufacturers leakage current rating!
If the maximum leakage current is reached before the rated blocking voltage is reached, STOP!
If the rated blocking voltage is reached before the rated leakage current is reached, STOP!
If possible, observe the E/I characteristics of the device on a X-Y oscilloscope.

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SIMPLE CLAMPING DEVICE
for
TESTING OF PRESSURE PACK DEVICES
The simple clamp arrangement below is sufficient for testing pressure pack devices, since the
force required to test these devices only has to be approx. 200 lbs.
SCRs/Thyristors
Diodes
NOTE : Diodes can have forward or reversed polarity. Polarity is determined by the direction
of the diode symbol stamped on the component, i.e. arrow pointing towards the stud (or base)
means forward polarity, arrow pointing towards the lead (or top) means reversed polarity.
Anode
Cathode
Cathode
Gate
Gate
Anode
Aux. Cathode
Anode Cathode
Gate
CONNECTIONS ON DIODES AND THYRISTORS

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OPERATING INSTRUCTIONS
*** CAUTION : UP TO 6400V ON TEST LEADS ***
INTRODUCTION
This Power Semiconductor Tester is designed to perform testing of power semiconductors, such as,
SCRs/Thyristors, Diodes, IGBTs, Transistors, and most MOS FETs.
The Cathode (Emitter) of the device under test is operated near ground potential.
The tester performs three tests : PFV (Peak Forward Voltage), PRV (Peak Reverse Voltage), and Gate
Voltage and Current to trigger (Base Current for Transistors). The test circuits are of the type recom-
mended by the JEDEC test standards RS397. The PRV/PFV tests applies a PEAK REVERSE VOLT-
AGE or PEAK FORWARD VOLTAGE, half wave 50-60 Hertz wave form to the device and the result-
ing peak leakage current is measured by a peak storage circuit and displayed on a peak reading ammeter.
The E/I curve of the device can be displayed on an X/Y oscilloscope. The DC Gate test is used to meas-
ure the DC gate voltage and current required to trigger the device into its On-state. The Anode
(Collector) supply is half wave 50/60 Hertz wave form.
The tester provides a Gate Voltage high enough to test for turn-on of IGBTs and MOS FETs.
Both NPN and PNP bipolar transistors can be tested.
PREPARATIONS AND PRECAUTIONS
Plug the tester into a properly grounded three wire receptacle.
When testing pressure pack components (hockey pucks), the component MUST be compressed at ap-
prox. 200-300 lbs. On page 5 is a suggested simple device for compressing these types of components.
It is recommended that the instrument is connected to ground via the GROUND terminal on the front
panel. Note: When testing IGBTs or Darlington Transistor modules, the base plate on the module un-
der test MUST be connected to the GROUND terminal.
NEVER keep the test button pressed over 15 seconds!
NEVER touch the test leads or the device under test while the “TEST” button is depressed.
Always turn the Voltage Control to the zero position before connecting or disconnecting the device un-
der test.
It is possible to observe the E/I curve of the device under test by connecting an oscilloscope to the con-
nector on the front panel with the optional 2 connector cable. Connect the BNC connector with a red and
black wire to the X-axis and the BNC connector with a green wire to the Y-axis. Set the X-axis to 0.2V/
div for a sensitivity of 200V/div and the Y-axis to 0.1V/div for a sensitivity of 1mA/div. The output sen-
sitivity is automatically changed when the function switch is moved to the Gate position. Note that the
Anode wave form is displayed during the gate test, not the E/I curve.

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SCRs (THYRISTORS)
Make sure the Voltage Control is at the zero position (fully counter clock-wise) before turning the unit
on. Connect the Anode, Gate and Cathode leads to the device to be tested. DO NOT MIX UP THE
ANODE AND CATHODE LEADS OR HIGH VOLTAGE WILL BE APPLIED TO THE GATE!
Place the function switch in the PRV position and press the “TEST” button.
Slowly raise the Voltage Control while observing the Peak Voltage and Peak Leakage Current on the
panel meters. In a properly functioning device, the rated voltage should be reached before the current
starts to rise rapidly, (the “break-over point”). If the break-over point is reached before the rated volt-
age, the device is marginal. UNDER NO CIRCUMSTANCES MUST THE RATED VOLTAGE
OF THE DEVICE BE EXCEEDED!
Return the Voltage Control to the zero position
Place the function switch in the PFV position, depress the “TEST” button and repeat steps 3 and 4.
Place the function switch in the GATE position and press the “TEST” button.
Slowly raise the Voltage Control while observing the “TRIGGER INDICATION” light. The Gate Volt-
age and Gate Current will be displayed on the panel meters. The meter reading should be taken just prior
to the trigger point to avoid incorrect readings due to a gate impedance change after turn-on.
Return the Voltage Control to the zero position and disconnect the device.
DIODES
Make sure the Voltage Control is at the zero position (fully counter clock-wise) before turning the unit
on. Connect the Anode and Cathode leads to the device to be tested.
Place the function switch in the PRV position and press the “TEST” button.
Slowly raise the Voltage Control while observing the Peak Voltage and Peak Leakage Current on the
panel meters. In a properly functioning device, the rated voltage should be reached before the current
starts to rise rapidly, (the “break-over point”). UNDER NO CIRCUMSTANCES MUST THE DE-
VICE’S RATED VOLTAGE BE EXCEEDED!
Return the Voltage Control to the zero position
NOTE : Diodes only have to be tested in one direction. In certain instances you may find it easier to
hook up a diode with the leads reversed in which case you would then test with the function switch set
to PFV.
TRANSISTORS
The procedure for testing transistors is basically the same as for SCRs, with the exception of terminolo-
gy:
Cathode = Emitter, Anode = Collector, Gate = Base.
All types of transistors can by tested, such as, Darlingtons, IGBTs, and bipolar transistors.

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TESTING SET-UP AND PROCEDURES
PRESSURE PACK (Hockey Puck) SCRs (Thyristors)
Make sure the Voltage Control is at the zero position (fully counter
clockwise) before turning the unit on. Connect the Anode, Gate and
Cathode leads to the device to be tested. DO NOT MIX UP THE
ANODE AND CATHODE LEADS OR HIGH VOLTAGE WILL BE
APPLIED TO THE GATE!
Place the function switch in the PRV position and press the “TEST”
button.
Slowly increase the voltage while observing the Peak Voltage and Peak
Leakage Current on the panel meters.
In a properly functioning device, the rated voltage should be reached
before the current starts to rise rapidly, (the “break-over point”).
Place the function switch in the PFV position and repeat procedure
described above.
Place the function switch in the GATE position and slowly raise the
Voltage Control while observing the “TRIGGER INDICATION” light.
If the light does not turn on, the Gate on the SCR is faulty, and the device
should be replaced.

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PRESSURE PACK (Hockey Puck) Diodes
Make sure the Voltage Control is at the zero position (fully counter
clockwise) before turning the unit on. Connect the Anode and Cathode
leads to the device to be tested.
NOTE : Diodes only have to be tested in one direction. If the diode is
forward biased (standard), the function switch should be in the PRV
position. If the diode is reversed biased, the function switch should be in
the PFV position.
Place the function switch in the PRV (PFV) position and press the “TEST”
button.
Slowly increase the voltage while observing the Peak Voltage and Peak
Leakage Current on the panel meters.
In a properly functioning device, the rated voltage should be reached before
the current starts to rise rapidly, (the “break-over point”).
Make sure the Voltage Control is at the zero position (fully counter
clockwise) before turning the unit on. Connect the Anode and Cathode
leads to the device to be tested.
NOTE : Diodes only have to be tested in one direction. If the diode is
forward biased (standard), the function switch should be in the PRV
position. If the diode is reversed biased, the function switch should be in
the PFV position.
Place the function switch in the PRV (PFV) position and press the “TEST”
button.
Slowly increase the voltage while observing the Peak Voltage and Peak
Leakage Current on the panel meters.
In a properly functioning device, the rated voltage should be reached before
the current starts to rise rapidly, (the “break-over point”).
STUD MOUNTED DIODES

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GTOs (Gate Turn Off Thyristors)
Make sure the Voltage Control is at the zero position (fully counter clock-
wise) before turning the unit on. Connect the Anode, Gate and Cathode leads
to the device to be tested. DO NOT MIX UP THE ANODE AND
CATHODE LEADS OR HIGH VOLTAGE WILL BE APPLIED TO
THE GATE!
Place the function switch in the PRV position and press the “TEST” button.
Slowly increase the voltage while observing the Peak Voltage and Peak
Leakage Current on the panel meters.
In a properly functioning device, the rated voltage should be reached before
the current starts to rise rapidly, (the “break-over point”).
Note: Most GTOs are “Anode Short” type, which means that the anode break
-over voltage is only between 17 and 19 volts.
Place the function switch in the PFV position and repeat procedure described
above.
Place the function switch in the GATE position and slowly raise the Voltage
Control while observing the “TRIGGER INDICATION” light.
If the light does not turn on, the Gate on the SCR is faulty, and the device
should be replaced.
Note: The Gate on a GTO turns on at a lower voltage than a SCR. Typical
values are between 0.6 and 0.8 volt.