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F-9

TROUBLESHOOTING & REPAIR

 

 

 

TROUBLESHOOTING GUIDE

 

 

 

Observe Safety Guidelines

 

 

 

 

 

 

 

 

 

detailed in the beginning of this manual.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PROBLEMS

 

POSSIBLE AREAS OF

RECOMMENDED

 

 

(SYMPTOMS)

 

 

 

MISADJUSTMENT(S)

 

 

COURSE OF ACTION

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

FUNCTION PROBLEMS

 

 

 

 

 

 

 

 

AC/DC Indicator on control panel

 

 

None

 

 

1.

Check leads #304 and #312 for

 

 

 

display show AC when polarity

 

 

 

 

 

 

proper connections. Refer to

 

 

 

switch is in the DC position, or vice

 

 

 

 

 

 

wiring diagram

 

 

 

versa — machine has output but

 

 

 

 

 

 

 

 

 

 

 

balance control is not operable in

 

 

 

 

 

2.

Check microswitch (S2A),

 

 

 

the AC TIG mode.

 

 

 

 

 

 

 

located on polarity switch (S2),

 

 

 

 

 

 

 

 

 

 

 

for proper operation.

 

 

 

 

 

 

 

 

 

 

3.

The protection/snubber board

 

 

 

 

 

 

 

 

 

 

 

may be faulty. See protection/

 

 

 

 

 

 

 

 

 

 

 

snubber board continuity test.

 

 

 

 

 

 

 

 

 

 

4.

Check control transformer (T2).

 

 

 

 

 

 

 

 

 

 

 

See control transformer voltage

 

 

 

 

 

 

 

 

 

 

 

test.

 

 

 

 

 

 

 

 

 

 

5.

If above checks are OK, then

 

 

 

 

 

 

 

 

 

 

 

replace the control board.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

All red keypad LEDS are dark

 

 

None

 

 

1.

The wiring harness between

 

 

 

but the control panel display is

 

 

 

 

 

 

the Control board and the LED

 

 

 

operable. The machine has output.

 

 

 

 

 

 

board may be faulty. Check for

 

 

 

 

 

 

 

 

 

 

 

defective plugs or loose wires.

 

 

 

 

 

 

 

 

 

 

2.

The Control board may be

 

 

 

 

 

 

 

 

 

 

 

faulty. Replace.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CAUTION

If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln Electric Service Department for technical troubleshooting assistance before you proceed call 216-383-2531 or 1-800-833-9353.

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Lincoln Electric SVM100-A service manual Troubleshooting & Repair