Thermal Dynamics Cutmaster 82, Service Manual

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cutmaster 82
Manual 0-4980 5-19 SERVICE
D. IGBT Modules Test
1. Disconnect transformer wires from Main PCB
terminals PRI 1 (A) and PRI 4 (D).
2. Using an ohmmeter perform the following
checks
IGBT A
Meter (+) Meter (-) Indication
PRI 1 (A) MTH 2 Forward Bias
PRI 1 (A) MTH 4 Reverse Bias
MTH 2 PRI 1 (A) Reverse Bias
MTH 4 PRI 1 (A) Forward Bias
PRI 2 (B) MTH 2 Forward Bias
PRI 2 (B) MTH 4 Reverse Bias
MTH 2 PRI 2 (B) Reverse Bias
MTH 4 PRI 2 (B) Forward Bias
IGBT B
Meter (+) Meter (-) Indication
PRI 3 (C) MTH 6 Forward Bias
PRI 3 (C) MTH 5 Reverse Bias
MTH 6 PRI 3 (C) Reverse Bias
MTH 5 PRI 3 (C) Forward Bias
PRI 4 (D) MTH 6 Forward Bias
PRI 4 (D) MTH 5 Reverse Bias
MTH 6 PRI 4 (D) Reverse Bias
MTH 5 PRI 4 (D) Forward Bias
3. If the test reveals a failed component, replace
Main Pcb and perform main contactor test – Sec-
tion 5.11A. If no problem is found, reconnect the
transformer wires to Main PCB.
E. Output Diode Module Test
1. Disconnect transformer wires from Main PCB
terminal SEC 1.
2. Using an ohmmeter perform the tests in the
chart
Output Diode Module
Meter (+) Meter (-) Indication
SEC 1 WORK 1 Forward Bias
SEC 1 CHOKE 1 Reverse Bias
WORK 1 SEC 1 Reverse Bias
CHOKE 1 SEC 1 Forward Bias
SEC 2 WORK 1 Forward Bias
SEC2 CHOKE 1 Reverse Bias
WORK 1 SEC2 Reverse Bias
CHOKE 1 SEC 2 Forward Bias
3. If the test reveals a failed component, replace
Main Pcb. If no problem is found, reconnect the
transformer wires to Main PCB.