Lincoln Electric 11519 Service Manual page 70

F-24
ACTIVE SCR RECTIFIER ASSEMBLY TEST (continued)
FIGURE F.6 — CONTROL BOARD MOLEX PLUG LOCATIONS FOR G4824 PC CONTROL BOARD
PROCEDURE
1. Disconnect main AC input power to the
machine.
2. Remove the case top and side panels with a 3/8
in. nutdriver.
3. Remove the tool tray with a 5/16 in. nutdriver.
4. Verify that the capacitors have completely dis-
charged with a volt-ohmmeter.
5. Disconnect plugs J6 and J5 control board. This
electrically isolates the SCR bridge assembly.
See Figure F.6.
TROUBLESHOOTING AND REPAIR
Power MIG® 255XT
J6
J5
J8
J1
J4
J3
J2
F-24