Lincoln Electric SVM186-A Benutzerhandbuch

TABLE OF CONTENTS - TROUBLESHOOTING AND REPAIR

F-1

Return

PRECISION TIG® 225

Troubleshooting and Repair.............................................................................................................................F-1

How to Use Troubleshooting Guide .......................................................................................................F-2

PC Board Troubleshooting Procedures and Replacement ....................................................................F-3

Troubleshooting Guide ...........................................................................................................................F-4

Test Procedures

High Frequency Circuit Disable Procedure ..........................................................................................F-15

T1 Transformer Test .............................................................................................................................F-17

Static SCR Test ....................................................................................................................................F-21

Active SCR Test ...................................................................................................................................F-25

Oscilloscope Waveforms

Normal Open Circuit Voltage Waveform-AC TIG Mode .......................................................................F-29

Normal Open Circuit Voltage Waveform-DC TIG Mode.......................................................................F-30

Normal Open Circuit Voltage Waveform-AC Stick Mode .....................................................................F-31

Normal Open Circuit Voltage Waveform-DC Stick Mode .....................................................................F-32

Typical Output Voltage Waveform-Machine Loaded AC TIG Mode .....................................................F-33

Typical Output Voltage Waveform-Machine Loaded DC TIG Mode.....................................................F-34

Typical Output Voltage Waveform-Machine Loaded AC Stick Mode ...................................................F-35

Typical Output Voltage Waveform-Machine Loaded DC Stick Mode...................................................F-36

Abnormal Open Circuit Voltage-DC TIG Mode One SCR not Functioning ..........................................F-37

Replacement Procedures

SCR Bridge Assembly Removal and Replacement .............................................................................F-39

Polarity Switch Removal and Replacement .........................................................................................F-45

High Voltage Transformer Removal and Replacement ........................................................................F-49

Main Transformer and Output Choke Removal and Replacement ......................................................F-53

Retest after Repair......................................................................................................................................F-55