Tweco 51 with SL100SV CutMaster - Manual (Page 97)

Manual 0-4640 5-33 SERVICE
5
2. Output Diode Circuit Test
WARNING
Disconnect primary power at the source before taking any resistance checks.
a. Use an ohmmeter set to the diode function and make the following measurements on the Output Diode Board to Main
Power PC Board.
Meter (+) Meter (-) Indication
E18 E21 Diode Drop
E21 E18 Open
E18 E20 Diode Drop
E20 E18 Open
E20 E19 Diode Drop
E19 E20 Open
E21 E19 Diode Drop
E19 E21 Open
E18 E19 (2) Diode Drops
E19 E18 Open
CutMaster 51 Output Diode
Test Readings
b. The meter should indicate a diode drop in one direction and an open in the other direction for each check. Replace Output
Diode Board if readings are not the same as the chart.
3. IGBT Circuit Test
a. Use an ohmmeter set to the diode function and make the following measurements on the IGBT Board to the Main Power
Board.
Meter (+) Meter (-) Meter (+) Meter (-) Indication
E3 E13 E35 E13 Diode Drop
E13 E3 E13 E35 Open
E15 E3 E15 E35 Diode Drop
E3 E15 E35 E15 Open
E15 E13 E15 E13 (2) Diode Drops
E13 E15 E13 E15 Open
208/230V
Power Supply
400V & 460V
Power Supply
CM51 IGBT Test Indications
b. The meter should indicate a diode drop in one direction and an open in the other direction for each check. Replace IGBT
Board if readings are not the same as the chart.
c. Activate the torch.
• After two seconds INV ON indicator on the Logic PCB should turn ON. If indicator does not turn ON, replace Logic
PCB.
d. Measure open circuit voltage between E7(+) to E10 (-) on the Main Power PC Board. Voltage should be greater than 200
vdc. If voltage is less than 10 vdc, refer to the output diode test measurements or IGBT module test measurements or
shorted torch measurements.