Kemppi Mastertig MLS 3003 ACDC Service Manual page 24

Measurements
Z003 Secondary inverter
- Power should be off
- Measure diodes and IGBTs in forward and reverse direction. Forward diode threshold voltage is
about 0,45V, reverse direction high.
- C-A, C-E, B-C, D-B, ~0,45V diode threshold voltage
B-E, 0,7V diode threshold voltage
D-C, 0,85V diode threshold voltage
D (aux-)
E (aux+)
A (in+, heat sink)
C (out+-)
B (in-)
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