Test Procedures; Tachometer Feedback Test - Lincoln LN-742 Service Manual

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TROUBLESHOOTING AND REPAIR

TEST PROCEDURES

Service and repair should only be performed by 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 technical troubleshooting assistance before you proceed. Call 216-383-2531
or 1-800-833-9353(WELD).
TEST DESCRIPTION
The following procedure will help determine if the tachometer circuit is receiving the
correct voltage and also if the tachometer is developing the correct feedback signal.
MATERIALS NEEDED
5/19" Nutdriver
Volt/Ohmmeter

TACHOMETER FEEDBACK TEST

WARNING
LN-742 & LN-742H
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