Lincoln Electric 11937 Service Manual page 28

F-14
PROCEDURE
1. Remove input power to the machine.
2. Perform the Case Cover Removal Procedure.
3. Locate the gas solenoid and lead connections.
Do not disconnect the leads. See Figure F.2.
4. Turn the machine on and pull the gun trigger to
WARNING
ELECTRIC SHOCK can kill.
• Have an electrician install and
service this equipment. Turn the
input power OFF at the fuse box
before working on equipment. Do
not touch electrically hot parts.
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conduct the voltage test.
5. There should be approximately 6.0 - 6.5 VDC
at the solenoid.
TROUBLESHOOTING AND REPAIR
GAS SOLENOID TEST
(continued)
FIGURE F.2 – GAS SOLENOID LOCATION & LEADS
Gas Solenoid
Leads
WIRE FEEDER WELDER (180 MODEL)
6. If the 6.0 - 6.5 VDC is missing or is low, check
the leads and connections between the solen-
oid and pins 7 and 8 in P3 on the control board.
See Wiring Diagram.
7. If the leads and connections are good to the
board, verify the correct supply voltage 18 -
32 VDC at pins 7 and 10 at P3 on the control
board. See Wiring Diagram.
8. If voltage is correct at P3, the control board
may be faulty. Replace the control board.
9. If the 6.0 - 6.5 VDC is present at the solenoid
leads and the solenoid does not activate, the
solenoid may be faulty. Normal solenoid coil
resistance is approximately 20-22 ohms.
10. The solenoid can be further checked by dis-
connecting the solenoid leads and applying
12VDC directly to the terminals. If the solenoid
does not activate, the solenoid is faulty.
11. Connect all disconnected leads and replace
the previously removed case cover.
F-14