Drive Motor And Tach Feedback Test - Lincoln Electric LF-72/74 Service Manual

TROUBLESHOOTING & REPAIR
F-7 F-7

DRIVE MOTOR AND TACH FEEDBACK TEST

WARNING
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 pre-
cautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to per-
form the test / repairs safely, contact the Lincoln Electric Service Department for
electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will help determine if the wire drive motor is receiving the correct voltage and
is capable of running properly. It will also determine if the tach sensor is receiving the
correct input from the control board, and is sending back the correct signal.
MATERIALS NEEDED
5/16 in. nut driver
32 VDC @ 1 amp variable power source
Volt-Ohm Meter
LF-72/74