Lincoln Electric SQUARE WAVE TIG 355 Service Manual page 130

F-78
INPUT CONTACTOR REMOVAL AND REPLACEMENT (continued)
PROCEDURE
1. Remove input power to the machine.
2. With the 5/16" nutdriver, remove the case top
and sides.
3. Perform the Input Power Factor Capacitor
Voltage Check.
4. With the 5/16" nutdriver, remove the rear
access panel.
For Steps 5-20, refer to Figure F.24.
5. With the slot head screw driver, remove the
input leads from the L1 and L2 terminals on the
input contactor.
6. With the slot head screw driver, remove the
copper strap, the heavy lead, and the small
capacitors from the output side of the contactor.
.
TROUBLESHOOTING AND REPAIR
FIGURE F.24 – INPUT CONTACTOR CONNECTIONS
SQUARE WAVE TIG 355
7. Remove small lead H1 from the L1 terminal.
8. Remove small lead #246 from the L2 terminal.
9. Remove leads #243 and #244 from the contac-
tor coil tabs.
10. Remove leads #243 and #242 from the contac-
tor interlock located on the bottom of the con-
tactor.
11. With the 5/16" nutdriver, remove the 4 screws
mounting the contactor bracket to the case
back.
12. Carefully remove the contactor and the bracket
assembly from the case back.
F-78