Lincoln Electric INVERTEC SVM158-A Service Manual page 135

F-85
REMOVAL AND REPLACEMENT (continued)
8. Under the copper plate previously removed, there
is an allen bolt. Remove it using a 9/64" allen
wrench. See Figure F.39.
9. Using a 7/16" socket remove the mounting bolts at
the top and bottom of the modules. See Figure
F.39.
10. The output rectifier modules are ready for removal
and/or replacement.
11. Before replacing the diode module, apply a thin
even coat of Penetrox A-13 heatsink compound
to the bottom surface of the diode module. Note:
Keep the compound away from the mounting
holes.
12. Press the module firmly against the sink while
aligning the mounting holes. Insert each outer
screw through a spring washer and then a plain
washer and into the holes. Start threading all
three screws into the heat sink (2 or 3 turns by
hand).
FIGURE F.39. – OUTPUT RECTIFIER MODULE MOUNTING BOLT LOCATIONS
40 20
3/16" Allen
Bolts
9/64" Allen
Bolts
TROUBLESHOOTING & REPAIR
OUTPUT RECTIFIER MODULES
Mounting
Bolts
X4 X2
Mounting
Bolts
V350-PRO
13. The screw threads may catch on the threads of
the heat sink, so be sure to get the face of the
screw into contact with the surface of the module
(using just hand torque).
14. Using a 7/16" socket, tighten each mounting bolt
to between 5 and 10 inch pounds.
15 Tighten the center allen screw to between 12 and
18 inch pounds.
16. Tighten each mounting bolt again (30 to 40 inch
pounds this time).
15. Replace leads #X2, #X4, #20, #40 to their original
terminals in their proper positions. Torque bolts to
30-40 Inch Pounds.
16. Perform the Snubber Board Replacement
Procedure detailed earlier in this section.
17. Replace the case wraparound cover.
F-85