Troubleshooting Guide - Lincoln Electric POWER MIG 255 SVM144-B Service Manual

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TROUBLESHOOTING GUIDE

PROBLEMS
(SYMPTOMS)
Major Physical or Electrical Damage
is Evident
Machine is dead — no open circuit
voltage output and no wire feed
when gun trigger is pulled. The
machine display may be lit.
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
1-888-935-3877.
TROUBLESHOOTING & REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
OUTPUT PROBLEMS
1. Contact your
Electric Authorized Field Service
Facility.
1. Make certain that the input
power switch is in the "ON" posi-
tion.
2. Check the input voltage at the
machine. Input voltage must
match the rating plate and the
reconnect panel.
3. Blown or missing fuses in the
input line.
4. The thermostats may be open
due to machine overheating. If
machine operates normally after
a cooling off period then check
for proper fan operation and
ventilation. Make certain that the
machine's duty cycle is not
being exceeded.
5. Check the trigger circuit. Leads
#324 to #325 should have conti-
nuity (zero ohms) when the gun
trigger is pulled. If not then the
gun may be faulty — replace.
6. Make sure unit is not connected
to a portable generator.
CAUTION
POWER MIG 255
detailed in the beginning of this manual.
RECOMMENDED
COURSE OF ACTION
local Lincoln 1. Contact The Lincoln Electric
Service Dept. 1-888-935-3877
1. Check input power switch (S1).
It may be faulty.
2. Check for lose or broken wires
at the reconnect panel.
3. Perform
Test.
4. Perform Rectifier Diode Bridge
Test.
5. Check the thermostats and
associated leads for loose or
broken connections. See wiring
diagram.
6. The control board may be faulty.
Replace.
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Observe Safety Guidelines
Main Transformer