Section F-1
TROUBLESHOOTING & REPAIR SECTION
Troubleshooting Guide................................................................................................F-4 - F-14
Test Procedures
Input Contactor Test......................................................................................................F-15
Active SCR Test.............................................................................................................F-29
Oscilloscope Waveforms .....................................................................................................F-33
Typical Output Voltage Waveform-Constant Voltage FCAW/GMAW............................F-36
Typical Output Voltage Waveform-Constant Voltage Subarc .......................................F-37
Replacement Procedures ....................................................................................................F-40
Retest After Repair ..............................................................................................................F-61
TABLE OF CONTENTS
IDEALARC DC-400
LINCOLN
®
ELECTRIC
Section F-1