Troubleshooting – Lincoln Electric IDEALARC R3R-500 User Manual
Page 79
REASSEMBLY
13. For reassembly, carefully place the SCR/ diode
assembly into position on the mounting brackets.
14. Replace and tighten the four nuts and lockwash-
ers that hold the SCR/diode assembly to the
mounting brackets.
15. Reattach the three heavy aluminum secondary
leads and snubber leads to the SCR finned heat
sinks. Apply a thin coating of Dow Corning 340
heat sink compound to connection points.
16. Attach plug J4 (or individual gate leads) to the
control board.
17. Attach the positive lead and shunt to the positive
heat sink plate.
18. Attach the two #220 leads to the right side of the
negative heat sink plate.
19. Connect the choke switch lead to the left side of
the negative heat sink plate. See Figure F.27.
20. Install the glastic stiffeners to the left and right
sides. See Figure F.27.
21. Attach the air deflector to the front panel (R3R
22. Check all lead placements and secure.
23. Attach the front assembly to the machine’s base.
24. Install the front control panel and case top and
sides.
TROUBLESHOOTING
F-45
F-45
IDEALARC R3R
SCR/DIODE RECTIFICER ASSEMBLY
REMOVAL AND REPLACEMENT (continued)