Lincoln Electric PRO-CUT 55 SVM140-A Service Manual page 67

F-30
TORCH CONTINUITY AND SOLENOID TEST (continued)
TEST
POINTS
Pin 7 to Pin 8
Pin 7 to Torch
Nozzle
Pin 8 to Torch
Nozzle
Pin 1 to Pin 9
Pin 1 to Pin 9
Pin 2 to Pin 3
Pin 7 to Torch
Electrode at machine
end of torch
Pin 8 to Torch
Electrode at machine
end of torch
Pin 7 To
Pin 1
Pin 2
Pin 3
Pin 9
Pin 8 To
Pin 1
Pin 2
Pin 3
Pin 9
Pins 1 & 9 to
all other pins
Pins 2 & 3 to
all other pins
4. If any of the resistance checks are not cor-
rect, the torch assembly may be faulty.
Repair or replace.
TROUBLESHOOTING & REPAIR
TABLE F.5 - TORCH ASSEMBLY RESISTANCES
CIRCUIT(S) BEING
TESTED
Parallel pilot arc
leads
One pilot arc lead to
nozzle
One pilot arc lead to
nozzle
Torch trigger circuit
Torch trigger circuit
Electrode Solenoid
Pilot and Electrode
circuit
Pilot and Electrode
circuit
Electrical Isolation
of Circuits
Electrical Isolation
of Circuits
Electrical Isolation
of Torch Trigger
Circuit
Electrical Isolation
of Torch Solenoid
Circuit
PRO-CUT 55
EXPECTED
RESISTANCE
1.5 ohms maximum
1.0 ohm maximum
1.0 ohm maximum
100K ohms minimum
1.0 ohm maximum
45 to 55 ohms
1.0 ohm maximum
1.0 ohm maximum
Open
(very high)
Open
(very high)
Open
(very high)
Open
(very high)
5. Carefully apply the 12 VDC supply to the
electrode solenoid. (positive to Pin 2 and
negative to Pin 3). The electrode solenoid
should activate. Listen for the solenoid
action in the torch handle. If the solenoid
does not activate, it may be faulty. Replace.
F-30
TEST
CONDITIONS
None
Torch consumables
in place
Torch consumables
in place
Torch trigger NOT
pulled (not activated)
Torch trigger pulled
(activated)
None
Torch consumables
in place
Torch consumables
in place
Torch
Consumables
Removed
Torch
Consumables
Removed
None
None