Do System Tests to Identify Defective Components
Powermax65/85/105 SYNC Troubleshooting Guide 810430 125
Test 13 – Pilot arc IGBT
Do this test to identify if the pilot arc IGBT is operating correctly.
1. Set the power switch on the plasma power supply to OFF (O), and disconnect the power cord.
2. Remove the plasma power supply cover and the component barrier.
3. Remove the cartridge from the torch, but make sure that the torch is connected to the plasma
power supply.
4. Measure the resistance between the
center contact on the torch head and the
work clamp. If the resistance is less than
5 kiloohms (k), continue with the next
step.
5. Measure the resistance between the
2 pilot arc screws on the power PCB.
Refer to Figure 36. If the resistance is less
than 5 kiloohms (k), replace the pilot arc
IGBT.
Figure 36 – Pilot arc IGBT screws on the power PCB
WORK
LEAD
J26 (J27)
J28 (J29)
Powermax65/85 SYNC Powermax105 SYNC