Lincoln Electric IDEALARC DC-1500 Service Manual page 91

F-57
SCR OUTPUT BRIDGE REPLACEMENT (continued)
REPLACEMENT PROCEDURE
1. Place rectifier #5 into the front of the unit.
2. Connect the bottom aluminum secondary lead
to the bottom heat sink of rectifier #5. Connect
the top aluminum secondary lead to the top
heat sink of rectifier #5.
3. Mount the rectifier to the horizontal baffle. (4
places)
4. Tighten the two aluminum secondary lead con-
nections on rectifier #5.
5. Place rectifier #4 into the rear of the unit. Route
the harness through the notch in the air baffle.
6. Connect the bottom aluminum secondary lead to
the bottom heat sink of rectifier #4. Connect the
top aluminum secondary lead to the top heat
sink of rectifier #4.
7. Mount the rectifier to the horizontal baffle. (4
places)
8. Tighten the two aluminum secondary lead con-
nections on rectifier #4.
9. Connect the GI and G2 leads to the terminal
strips on rectifier #4.
10. Connect lead #212 to the top thermostat on
rectifier #4.
11. Route harness leads G6 and #211 to the other
side of the machine.
12. At the p.c. board enclosure area, route the har-
ness through the copper strap on rectifier #4.
13. Connect the G3 and G4 leads to the terminal
strips on rectifier #5.
14. Connect the molex plug to the snubber p.c.
board on rectifier #4.
15. Connect lead #247 to the top thermostat on
rectifier #4.
16. Connect lead # 242 to the top aluminum sec-
ondary lead on rectifier #4. Connect lead # 245
to the bottom aluminum secondary lead on rec-
tifier #4.
17. Connect lead #241 to the top aluminum sec-
ondary lead on rectifier #5. Connect lead # 244
to the bottom aluminum secondary lead on rec-
tifier #5.
18. Tighten all (4) flex lead connections to the alu-
minum secondary leads.
19. Place rectifier #6 into the rear of the unit.
TROUBLESHOOTING AND REPAIR
IDEALARC® DC-1500
20. Connect the bottom aluminum secondary lead
to the bottom heat sink of rectifier #6. Connect
the top aluminum secondary lead to the top
heat sink of rectifier #6.
21. Tighten all rectifier mounting bolts. (12 places)
22. Tighten the two aluminum secondary lead con-
nections on rectifier #6.
23. Connect lead #240 to the top aluminum sec-
ondary lead on rectifier #6. Connect lead #243
to the bottom aluminum secondary lead on rec-
tifier #6.
24. Tighten both flex lead connections to the alu-
minum secondary leads.
25. Connect the G5 and G6 leads to the terminal
strips on rectifier #6.
26. Connect leads #211 and #247 to the top ther-
mostat on rectifier #6.
27. Anchor the lead harness at the G1, G2 and G6
terminal strip locations.
28. Place the L-shaped copper leads between the
rectifier copper straps. Connect both copper
leads to the shunt. (2 places) Connect both
copper leads to the rectifier copper straps. (3
places) Note: The rectifier #4 connection also
includes (3) flex leads. Tighten all.
29. Inspect for any shorted turns between the sec-
ondary coil turns and the six secondary lead
stick outs.
30. Place the p.c. board enclosure in place.
31. Route the lead bundle through the cutout in the
enclosure.
32. Mount to the horizontal baffle with self-tapping
screws. (2 places)
33. Mount the enclosure braces to rectifier #5. (2
places) (use the smaller silver colored screws)
34. While using a static strap mount the Firing p.c.
board. (6 places)
35. Mount the 5CR relay.
36. Mount the 2CR relay.
37. Connect the ground lead to the p.c. board
enclosure.
38. Connect all molex plugs to the two p.c. boards.
39.Connect leads #74 and the ground lead to the
control p.c. board.
F-57