Lincoln Electric 10372 Service Manual page 137

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SWITCH BO RD
8. With the slot head screwdriver, remove
the two nylon mounting screws at the
bottom of the switch board. Note
placement of the shake-proof washers
and fiber spacers.
9. Using the 3/16 in. Allen wrench, care-
fully remove the four cap screws that
mount the switch board to the
heatsink.
10. Carefully remove the switch board from
the heatsink.
11. If the filter capacitor is to be removed,
carefully slide it out of the mounting
bracket.
REPL CEMENT PROCEDURE
1. If the filter capacitor is to be replaced,
carefully slide the new capacitor into
the mounting bracket. Position the
capacitor so the correct polarity termi-
nal is lined up with the correct hole on
the switch board.
2. All heatsink and IGBT mounting sur-
faces must be clean.
3. Apply a thin coat of thermal compound
(Penetrox A13) 0.005 in. to 0.010 in. to
the mating surfaces. Do not apply
around mounting holes.
4. Apply a thin coat of Penetrox A13 to
the capacitor terminals. Be careful not
to apply compound to screw threads
TROUBLESHOOTING ND REP IR
ND FILTER C P CITOR REMOV L
ND REPL CEMENT ( ontinued)
POWER W VE 455/POWER FEED 10
or threaded area of terminals.
5. Mount the new switch board and tight-
en the four cap head screws in the fol-
lowing manner.
• Tighten all until snug.
• Tighten all from 24 to 28 in/lbs.
• Tighten all from 40 to 48 in/lbs.
6. Make sure the capacitor is positioned
correctly. Connect leads 19+ and 20-
to the correct terminals. Tighten to
55 in/lbs.
7. Position and mount the two nylon
screws, fiber spacers, and washers.
Torque from 4 to 8 in/lbs.
8. Connect leads 11/12 or 15/16 to the
correct terminal.
9. Connect leads 13/14 or 17/18 to the
correct terminal.
10. Connect the molex plug to the top of
the switch board.
11. Install the case top and sides using the
3/8 in. nutdriver.
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