E-3

 

TROUBLESHOOTING

E-3

 

 

 

 

 

Observe all Safety Guidelines detailed throughout this manual

 

 

 

 

 

PROBLEMS

POSSIBLE CAUSE

RECOMMENDED

 

(SYMPTOMS)

COURSE OF ACTION

 

 

 

 

 

 

 

 

FUNCTION PROBLEMS

 

 

 

 

Welder runs but fails to generate

Generator or exciter brushes may

Be sure that all brushes bear on the

current.

be loose or missing.

commutator and have proper spring

 

 

 

tension.

 

 

Exciter may not be operating.

Check exciter output voltage with

 

 

 

voltmeter or lamp.

 

 

Field circuit of generator or exciter

Check for open circuits in rheostat,

 

 

may be open.

field leads and field coils. Also check

 

 

 

resistors.

 

 

Polarity reversing switch may be in

Put handle in positive or negative

 

 

the neutral position.

position.

 

 

Exciter may have lost excitation.

Check components and continuity in

 

 

 

flashing circuit.

Welding arc is loud and spatters

Series field circuit may be open cir-

Check circuit with ringer or volt-

excessively.

cuited.

meter.

 

Current setting may be too high.

Check setting and current output

 

 

with ammeter.

 

Polarity may be wrong.

Check polarity. Try reversing polarity

 

 

or try an electrode of the opposite

 

 

polarity.

CAUTION

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.

SAE400 & SAE400 WELD’N AIR

Page 27
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