Victor CUTMASTER 102, Service Manual

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CUTMASTER 102
Manual 0-4998 SERVICE
5-17
Fan MOT 1 turns ON without START signal being
activated. (Rev AB & earlier)
1. Open connection between J2 on Capacitor PCB to J3
on 40A PCB.
2. Defective Main PCB
a) Measure for approximately 325VDC between MTH
1 to MTH 7
3. Capacitor 12VDC bias supply voltage missing
a) Disconnect plug from J2 on Capacitor PCB and
measure for 12VDC between J2-1 to J2-2. If not
correct replace Capacitor PCB
4. Defective 40A PCB
See 40A PCB exclusion
Fans MOT 2 and MOT 3 do not turn ON when
START signal is activated
1. Shorted fans MOT 2 or MOT 3
2. Bad connection on wires from J2 on Capacitor PCB to
J3 on 40A PCB.
3. No +12VDC Bias Supply voltage from Capacitor PCB
from J2.
4. Loose/unplugged connections on J12 on Main PCB /
J1 on Capacitor PCB
Air flow does not momentarily turn OFF then back
ON after the START signal is active.
1. Defective start cartridge
2. Torch O-ring has moved into wrong groove.
Internal visual checks:
1. Loose/unplugged connections on J12 on Main PCB
and J1 on Capacitor PCB.
2. Loose/unplugged connections on J2 on Main PCB and
J1 on Logic PCB.
3. Loose/unplugged connections on J2 on Capacitor PCB
and J3 on 40A PCB.
4. Sync cable unplugged from Main PCB or 40A PCB.
5. Loose/unplugged connection on J5 on Main PCB.
40A PCB exclusion
Disconnect J4 & J9 connectors and remove wire from CHOKE1
terminal.
Measure Capacitor PCB bias supply between J21 to J2-2 for
12VDC. If 40A PCB is at fault, the unit will function but with
reduced output current.
Perform Pre power-up checks
1. W1
2. Open Input Diode – Input rectifier D1 on Main PCB or
40A PCB
3. Shorted/Open IGBT s
4. Output Diodes on both Main PCB and 40A PCB.
5. Torch / parts
Power checks:
1. Low input voltage or missing phase
a) Measure voltage under load
2. Defective W1 contactor.
a) Measure output of W1 under load
3. Shorted Sync cable
4. Open connection between J2 on Capacitor PCB to J3
on 40A PCB.
5. Defective Logic PCB (with Ribbon cable)
a) Open connection in ribbon cable
b) Measure Logic PCB for relay configuration signals
J1-4 to J1-25 (Low for 460V= < 1VDC)
J1-5 to J1-25 (Low for 230V= < 1VDC)
With START signal active
1. Measure Logic PCB CUR_SET signal between J1-6 to
J1-25. If missing replace Logic PCB
2. Measure Logic PCB for SHUTDN signal between J2-10
to J2-25 to go low while continuing to activate the start
signal.
If voltage does not go low, replace Logic PCB.
3. Defective Main PCB
a) Measure for approximately 325VDC on a 230V
system, 650VDC on a 460V system and 850VDC
on a 600V system between MTH 1 to MTH 7 under
load. Readings a lot lower than these will indicate
a defective PCB.
4. Capacitor 12VDC bias supply voltage missing
a) Disconnect plug from J2 on Capacitor PCB and
measure for 12VDC between J2-1 to J2-2.
If not correct, replace Capacitor PCB
5. Defective 40A PCB
See 40A PCB exclusion
6. Defective Main PCB