Static Scr Test - Lincoln Electric PRECISION TIG SVM186-A Service Manual

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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 trou-
bleshooting assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This procedure is a quick check to determine if an SCR is shorted or "leaky". See
machine waveform section for normal and abnormal SCR waveforms.
MATERIALS NEEDED
Volt/Ohm Meter (Analog)
PRECISION TIG® 225 Wiring Diagrams
3/8" nutdriver
SCR Heat Sink Assembly Drawing
TROUBLESHOOTING AND REPAIR

STATIC SCR TEST

WARNING
PRECISION TIG® 225
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