Lincoln Electric R3R-500, R3R-300 manual

Return to Master TOC

Section F-1

- TROUBLESHOOTING & REPAIR SECTION -

Troubleshooting & Repair Section	Section F
How to Use Troubleshooting Guide	F-2
PC Board Troubleshooting Procedures	F-3
Troubleshooting Guide	F-4 - F-9
Test Procedures
Input Contactor Test (Equipped with AC Coil)	F-10
Input Contactor Test (R3R 300 Equipped with DC Coil)	F-13
Control Transformer (T2) Voltage Test	F-16
Main Transformer (T1) Voltage Test	F-19
Static SCR/Diode Rectifier Bridge Test	F-24
Active SCR Test	F-28
Pocket Amptrol Circuit Test	F-31
Oscilloscope Waveforms	F-35
Normal Open Circuit Voltage Waveform-Maximum Output, No Load	F-35
Typical Output Voltage Waveform-Machine Loaded	F-36
Typical SCR Gate Voltage Waveform-Maximum Output, No Load	F-37
Abnormal Open Circuit Voltage Waveform-One Output SCR Not Functioning	F-38
Replacement Procedures	F-39
Input Contactor (CR1) Cleaning/Replacement	F-39
Fan Motor and Blade Removal and Replacement	F-41
SCR/Diode Rectifier Assembly Removal and Replacement	F-43
SCR Removal and Replacement	F-46
Mounting of Stud Type Diodes to Aluminum Heat Sinks	F-52
Main Transformer Removal and Replacement	F-54
Retest After Repair	F-61

NOTE: This manual is based primarily on the model R3R

500.Where tests or other procedures differ sig- nificantly for models R3R 300 and R3R 400, those differences are noted.