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Welder troubleshooting, Caution – Lincoln Electric SA-250 User Manual

Page 21

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WELDER TROUBLESHOOTING

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SA 250

Observe all Safety Guidelines detailed throughout 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

(SYMPTOMS)

POSSIBLE AREAS OF

MISADJUSTMENTS(S)

RECOMMENDED

COURSE OF ACTION

Machine fails to hold the heat
consistently.

Welder starts but fails to generate
current.

Welding arc is loud and spatters
excessively.

Welding current too great or too
small compared to indication on
the dial.

Arc continuously pops out.

1. Rough or dirty commutator.

2. Brushes may be worn down

to limit.

3. Field circuit may have variable

resistance connection or intermit-
tent open circuit due to loose
connection or broken wire.

4. Electrode lead or work lead con-

nection may be poor.

5. Wrong grade of brushes may

have been installed on generator.

6. Field rheostat may be making

poor contact and overheating.

1. Generator or exciter brushes

may be loose or missing.

2. Exciter may not be operating.

3. Field circuit of generator or

exciter may be open.

4. Exciter may have lost excitation.

5. Series field and armature circuit

may be open-circuited.

1. Current setting may be to high.

2. Polarity may be wrong.

1. Exciter output low causing low

output compared to dial indication.

2. Operating speed too low or to

high.

1.

Current Range Selector

switch

may be set at an intermediate
position.

If all recommended possible areas
of misadjustment have been
checked and the problem persists,

Contact your local Lincoln
Authorized Field Service Facility.