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MASTER TABLE OF CONTENTS FOR ALL SECTIONS
Safety ...................................................................................................................................................................i-iv
Installation...............................................................................................................................................Section A
Technical Specifications ...............................................................................................................................A-2
Safety Precautions .......................................................................................................................................A-3
Input Supply Connections ............................................................................................................................A-4
Input Reconnect Procedure .........................................................................................................................A-5
User Supplied Connectors ...........................................................................................................................A-6
Output Connections......................................................................................................................................A-6
Work Cable Connection ...............................................................................................................................A-6
TIG Torch Connection ..................................................................................................................................A-7
Twist-Mate Adapter for LA-9 and LA-17 TIG Torch ......................................................................................A-8
Operation.................................................................................................................................................Section B
Safety Precautions .......................................................................................................................................B-2
General Description......................................................................................................................................B-3
Welding Capability........................................................................................................................................B-4
Limitations ....................................................................................................................................................B-4
Controls and Settings ...................................................................................................................................B-5
Welding Operation........................................................................................................................................B-6
Stick Welding................................................................................................................................................B-9
Auxiliary Power.............................................................................................................................................B-9
Accessories ............................................................................................................................................Section C
Maintenance............................................................................................................................................Section D
Safety Precautions .......................................................................................................................................D-2
Overload Protection .....................................................................................................................................D-2
Fan As Needed (F.A.N.) ...............................................................................................................................D-2
Service Procedures......................................................................................................................................D-2
Component Location and Access ................................................................................................................D-3
Spark Gap Adjustment .................................................................................................................................D-3
Theory of Operation ...............................................................................................................................Section E
General Description......................................................................................................................................E-2
Input Power Circuit .......................................................................................................................................E-2
DC Welding Output ......................................................................................................................................E-5
AC Welding Output.......................................................................................................................................E-6
SCR Operation .............................................................................................................................................E-7
Protective Circuits ........................................................................................................................................E-8
Troubleshooting and Repair ..................................................................................................................Section F
Troubleshooting Guide .................................................................................................................................F-4
Test Procedures..........................................................................................................................................F-18
Oscilloscope Waveforms ............................................................................................................................F-33
Replacement Procedures ...........................................................................................................................F-42
Retest After Repair .....................................................................................................................................F-59
Electrical Diagrams ................................................................................................................................Section G
Parts Manual .......................................................................................................................................P316 Series
RETURN TO MAIN INDEX
SQUARE WAVE TIG 275
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