Thermal Dynamics Cutmaster 82, Service Manual

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cutmaster 82
SERVICE 5-16 Manual 0-4980
3. Defective Main PCB
a) With Torch Switch closed, measure voltage
on Main PCB between test points GND1 to
I_DMD1 for 1.4 VDC. Replace Main PCB if
voltage is present.
B. SHORTED TORCH FAULT
After torch switch is closed, gas flows for two (2)
seconds then momentarily shuts off then back
on, FAULT INDICATOR flashes, and 85 PSI LED
flashes.
1. Upper O-Ring on torch head is in the wrong posi-
tion.
a) Remove shield cup from torch; check position
of the upper o-ring and correct if needed.
Upper Groove
with Vent Holes
Must Remain Open
Threads
Upper O-Ring
in Correct Groove
Lower O-Ring
Art # A-03725
2. Torch start cartridge is stuck.
a) Turn off power supply. Bleed down the system.
Remove the shield cup, tip,start cartridge and
electrode. Check the lower end unit of the
start cartridge for free movement. Replace
the cartridge if the lower end unit does not
move freely.
3. Worn or faulty torch parts
a) Inspect torch consumables parts. Replace if
necessary.
4. Shorted Torch
a) Disconnect torch from unit. With consumables
removed from the torch, Check continuity of
torch at ATC, between negative/plasma lead
connection to pilot lead connection.
Negative / Plasma Lead
4 Torch Switch
3 Torch Switch
2 PIP
1 PIP
Pilot Lead
Art # A-08124
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
depressed. If voltage does not drop replace Logic
PCB
b) While pilot arc is established, measure voltage
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) 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
a) Install jumper on Main PCB between test point
GND1 to terminal TIP1.
b) Close torch switch. If Pilot starts, replace Main
PCB