E-7

 

TROUBLESHOOTING

E-7

 

 

 

 

 

 

Observe all Safety Guidelines detailed throughout this manual

 

 

 

 

 

 

PROBLEMS

POSSIBLE AREAS OF

RECOMMENDED

 

 

(SYMPTOMS)

MISADJUSTMENTS

COURSE OF ACTION

 

 

 

 

 

 

TIG PROBLEMS

Arc "pulsates" in AC polarity,

DC

1.Micro switch S2A on polarity switch

polarity is o.k.

 

 

does not open in AC polarity

 

 

 

 

 

Black area along weld bead

 

1.

Oily or organic contamination from

 

 

 

work piece

 

 

 

 

2.

Tungsten electrode may be conta-

 

 

 

minated

 

 

 

 

3.

Leaks in gas line, torch, or con-

 

 

 

nections

 

 

 

 

 

Output quits momentarily; gas flow

1.

May be caused by hi-freq interfer-

and hi-freq are also interrupted

 

 

ence. Check that machine is

 

 

 

grounded

properly. Surrounding

 

 

 

machines that generate hi-freq

 

 

 

also should be properly grounded.

 

 

2.

Ground connection of Protection

 

 

 

PC board may has become loose

 

 

3.

Ground

connection

of

 

 

 

Bypass/Stabilizer PC board

may

 

 

 

has become loose.

 

 

 

 

 

 

 

 

 

 

 

 

 

If all recommended possible areas of misadjustment have been checked and the problem persists, Contact your local Lincoln Authorized Field Service Facility.

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.

PRECISION TIG 375

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Lincoln Electric IM936 manual TIG Problems