Lincoln Electric CLASSIC IM514-A - Manual (Page 20)

E-2 TROUBLESHOOTING E-2
CLASSIC I
LINCOLN
ELECTRIC ELECTRIC
®
Observe all Safety Guidelines detailed througout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSES
RECOMMENDED
COURSE OF ACTION
1. Machine fails to hold the heat
constantly.
2. Welder starts but fails to generate
current.
3. Welding arc is loud and spatters
excessively.
a. Rough or dirty commutator.
b. Brushes may be worn down to
limit.
c. Field circuit may have variable
resistance connection or intermit-
tent open circuit due to loose, or
broken wire.
d. Electrode lead or work lead con-
nection may be poor.
e. Wrong grade of brushes may
have been installed on generator.
f. Field rheostat may be making
poor contact and overheating.
a. Generator or exciter brushes may
be loose or missing.
b. Exciter may not be operating.
c. Field circuit of generator or
exciter may be open.
d. Exciter may have lost excitation.
e. Series field and armature circuit
may be open-circuited.
a. Current setting may be too high.
b. Polarity may be wrong.
a. Commutator should be turned or
cleaned.
b. Replace brushes.
c. Check field current with ammeter
to discover varying current. This
applies to both the main genera-
tor and exciter.
d. Tighten all connections.
e. Use Lincoln brushes.
f. Inspect and clean the rheostat.
a. Be sure that all brushes bear on
the commutator and have proper
spring tension.
b. Check exciter output voltage with
voltmeter or lamp.
c. Check for open circuits in rheo-
stat, field leads, and field coils.
Check rectifier bridge.
d. Flash fields. **
e. Check circuit with ringer or volt-
meter.
a. Check setting and current output
with ammeter.
b. Check polarity. Try reversing
polarity or try an electrode of the
opposite polarity.