Igbt Testing - Powertronix Quasar Service Manual

Service Manual

7.8.4 - IGBT testing

Two types of IGBT are used on the series UPS.
All the devices currently used on the , are the latest `advanced second' or `third' generation type,
these have a higher gate emitter impedance. Difficulty can be experienced testing this type of IGBT
using a standard DVM, as they lack the battery power to switch on the device.
This difficulty can give rise to an incorrect diagnosis and a perfectly serviceable IGBT may be marked
as defective.
As a normal DVM cannot produce a high enough voltage to switch on a advanced second or third gener
ation IGBT, it is recommended that the functional test is carried out with the use of an external dc power
supply.
Note: A 9V PP3 battery can successfully be used as the external voltage source.
Table 7-8 Third generation IGBT usage
Testing the IGBT
3x3 UPS
Issue 2 - November 2001
a) Twin pack devices used in the inverter section.
b) A single pack devices used on the converter.
Circuit Ref.
IGBT Q1, Q2, Q3
IGBT Q4
1. Power down the UPS and gain access to the power sections by following the procedure on
page 7 3.
2. Ensure that the power sections have been completely isolated, check using a DVM.
3. Locate the IGBT to be tested and totally isolate it by disconnecting its gate drive lead from
the inverter drivers and feedback PCB, and the power leads from the screwed terminals.
4. Test the IGBT using a DVM and a 9V dc power source.
Follow the procedure shown in Table 7 6. Refer to Figure 7 11 for the IGBT internal circuit.
5. Replace the IGBT if required.
Ensure the correct fitting procedure is used. Refer to Table 7 4 for correct torque values.
6. Reconnect the IGBT gate drive and power connections.
7. Carry out a test of the Inverter or Converter.
8. Replace all panels removed and restore the UPS to its normal working condition.
Hinet Third Generation IGBT's
IGBT Type
EUPEC BSM150GB120DN2
EUPEC BSM200GA120DN2 (6)
Test Procedures
Liebert Hiross Part Nº
Twin 0CATR210415
Single 0CATD212420
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