Thermal Dynamics cutmaster A60, Service Manual

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CUTMASTER A60
SERVICE 5-14 Manual 0-4982
C. AC LED ON, TEMP LED OFF, GAS LED
ON, gas flowing, DC LED OFF, Fault
Indicators OFF, No arc in torch
1. Defective Logic PCB
a) Measure voltage at Main PCB between test
point GND1 to J2-10.
Voltage is normally 12VDC and should drop to less
than 2VDC two (2) seconds after torch switch is de-
pressed. If voltage does not drop replace Logic PCB
b) While pilot arc is established, measure volt-
age on Main PCB between test points GND1
to I_DMD1 for 1.4 VDC. If voltage is low or
not present, replace Logic PCB.
2. Defective Main PCB
a) Measure voltage at Main PCB between test
point GND1 to J2-10.
Voltage is normally 12VDC and should drop to less
than 2VDC two (2) seconds after torch switch is de-
pressed. If voltage does not drop to less than 2VDC
for approx one (1) second then replace Main PCB
D. AC LED ON, TEMP LED OFF, GAS LED
ON, gas flowing, DC LED ON, Fault
Indicators OFF, No arc in torch.
1. Defective Main PCB
Install jumper on Main PCB between test point
GND1 to terminal TIP1.
b) Close torch switch. If Pilot starts, replace Main
PCB
E. AC LED ON, TEMP LED OFF, GAS LED
ON, gas flowing, DC LED ON, Fault
Indicators OFF, Pilot Arc is intermittent.
1. Defective Logic PCB
a) Measure for 12VDC on Main PCB between
test Point GND1 to J2-8. If 12VDC is present,
replace Logic PCB
2. Defective Main PCB
a) Replace Main PCB
F. INTERNAL ERROR FAULT INDICATOR AND
90 PSI INDICATOR FLASHING
1. There has been a microprocessor problem.
a) Turn ON/OFF SWITCH to OFF position and
then turn to ON position to clear the error
5.09 Main Arc and Controls
Problems
A. Main arc will not establish, LED D59 ON
Main PCB remains ON while pilot arc is
striking the work piece.
1. Work Cable not connected.
a) Connect cable to work piece
2. Work cable open / broken.
a) Check continuity of work cable. Insure con-
nection of cable to clamp is secure.
B. Main arc transfers but current cannot be
adjusted
1. Defective Logic PCB
a) While main arc is transferred,measure volt-
age on Main PCB between test points GND1
to I_DMD1.
b) Adjust CURRENT CONTROL POTENTIOM-
ETER from maximum to minimum. Voltage
should vary from 4VDC at max to 1 VDC at
min
If voltage does not vary with CURRENT CONTROL
POTENTIOMETER, replace Logic PCB
2. Defective Main PCB
a) Replace Main PCB
C. With CURRENT CONTROL
POTENTIOMETER set at maximum, output
current is only 60 amps.
1. Tip is touching the work piece, Drag mode.
a) Lift tip off work piece
2. Defective Pilot IGBT on Main PCB
a) Check per section 4.10-I
D. In RAPID AUTO RESTART mode, with
torch switch closed, the pilot does not
start immediately when the cutting arc
extinguishes
1. Defective Logic PCB
a) Replace Logic PCB
E. INTERNAL ERROR FAULT INDICATOR AND
90 PSI INDICATOR FLASHING
1. There has been a microprocessor problem.
a) Turn ON/OFF SWITCH to OFF position and
then turn to ON position to clear the error