D1 Rectifier Removal And Replacement Procedure - Lincoln Electric LN-25x Service Manual

LINCOLN ELECTRIC

D1 RECTIFIER REMOVAL AND REPLACEMENT PROCEDURE

Service and repair should be performed by only Lincoln Electric factory trained personnel. Unauthorized
repairs performed on this equipment may result in danger to the technician or machine operator and will
invalidate your factory warranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual. If for any reason you do not understand the test
procedures or are unable to perform the test/repairs safely, contact the Lincoln Electric Service Department
for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This procedure will aid the technician in the removal and replacement of the D1 Rectifier.
MATERIALS NEEDED
3/8" Nutdriver
Wiring Diagram
Dow Corning 340 Heat Sink Compound (Lincoln Part #T12837)
REMOVAL PROCEDURE
1. Remove the input power to the LN-25x wire feeder.
2. Perform the Wire Drive Assembly And Control Box Cover Removal Procedure.
3. Label and disconnect leads 667A, 667B, 67, 67C, 621A, 821 and 821A from the D1 rectifier. See
Figure F.21. See Wiring Diagram.
4. Using a 3/8" nutdriver, remove the nut securing the D1 rectifier to the rear of the front panel. See
Figure F.22.
5. The D1 rectifier can now be removed and replaced.
REPLACEMENT PROCEDURE
1. Clean the mounting surface on the rear of the front panel before installing the new D1
2. Apply a coating of Dow Corning 340 heat sink compound (Lincoln part #T12837) to the rear of the
rectifier.
3. Using a 3/8" nutdriver, attach the nut securing the D1 rectifier to the front panel.
4. Connect leads 667A, 667B, 67, 67C, 621A, 821 and 821A to the D1 rectifier. See Wiring Diagram.
5. Perform the Wire Drive Assembly And Control Box Cover Replacement Procedure.
6. Perform the Retest After Repair Procedure.
LN-25x™ Service Manual
rectifier.
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