E-2

 

 

 

 

TROUBLESHOOTING

E-2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

WELDER TROUBLESHOOTING

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TROUBLE

 

 

CAUSES

 

WHAT TO DO

 

 

 

 

 

 

 

 

 

 

 

 

 

1.

Machine fails to hold

 

a.

Rough or dirty commutator.

a.

Commutator should be turned or

 

 

 

 

the heat consistently.

 

 

 

 

cleaned.

 

 

 

 

 

 

 

b.

Brushes may be worn down to

b.

Replace brushes.

 

 

 

 

 

 

 

 

limit.

 

 

 

 

 

 

 

 

 

c.

Field circuit may have variable

c.

Check field current with ammeter to

 

 

 

 

 

 

 

 

resistance connection or

 

discover varying current. This

 

 

 

 

 

 

 

 

intermittent open circuit due to

 

applies to both the main generator

 

 

 

 

 

 

 

 

loose connection or broken wire.

 

and exciter.

 

 

 

 

 

 

 

d.

Electrode lead or work lead

d.

Tighten all connections.

 

 

 

 

 

 

 

 

connection may be poor.

 

 

 

 

 

 

 

 

 

e.

Wrong grade of brushes may

e.

Use Lincoln brushes.

 

 

 

 

 

 

 

 

have been installed on generator.

 

 

 

 

 

 

 

 

 

f.

Field rheostat may be making

f.

Inspect and clean the rheostat.

 

 

 

 

 

 

 

 

poor contact and overheating.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2.

Welder starts but fails

 

a.

Generator or exciter brushes

a.

Be sure that all brushes bear on the

 

 

 

 

to generate current.

 

 

may be loose or missing.

 

commutator and have proper spring

 

 

 

 

 

 

 

 

 

 

tension.

 

 

 

 

 

 

 

b.

Exciter may not be operating.

b.

Check exciter output voltage with

 

 

 

 

 

 

 

 

 

 

voltmeter or lamp.

 

 

 

 

 

 

 

c.

Field circuit of generator or

c.

Check for open circuits in rheostat,

 

 

 

 

 

 

 

 

exciter may be open.

 

field leads, and field coils. Check

 

 

 

 

 

 

 

 

 

 

rectifier bridge.

 

 

 

 

 

 

 

d.

Exciter may have lost excitation.

d.

Flash fields. (1) Check flashing

 

 

 

 

 

 

 

 

 

 

diode at 5 o’clock brushholder in

 

 

 

 

 

 

 

 

 

 

generator.

 

 

 

 

 

 

 

e.

Series field and armature circuit

e.

Check circuit with ringer or voltmeter.

 

 

 

 

 

 

 

 

may be open-circuited.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(1)FLASHING THE FIELDS:

1.Stop the engine welder and remove the cover from the exciter.

2.Turn the “Fine Adjustment Control” (rheostat) to “100” on the dial.

3.Using a 12 volt automotive battery, connect it’s negative terminal to the negative brushholder. The negative brushholder is the one nearest to the rotor lamination. See the wiring diagram. With the engine NOT running, touch the positive battery terminal to the positive brushholder. Remove the battery from the circuit.

4.Replace the exciter cover. Start the welder and the generator voltage should build up.

3.

Welding arc is loud and

a.

Current setting may be too high.

a.

Check setting and current output with ammeter.

 

spatters excessively

 

 

 

 

 

 

b.

Polarity may be wrong.

b.

Check polarity. Try reversing polarity or try an

 

 

 

 

 

electrode of the opposite polarity.

4.

Welding current too great or too

a.

Exciter output low causing low output

a.

Check exciter field circuit.

 

small compared to indication on

 

compared to dial indication.

 

 

 

the dial.

 

 

 

 

 

 

b.

Operating speed too low or too high.

b.

Adjust speed screw on governor for 1800 rpm

 

 

 

 

 

operating speed.

5.

Arc continuously pops out.

a.

“Current Range Selector” switch may be

a.

Set the switch at the center of the current range

 

 

 

set at an intermediate position.

 

desired.

 

 

 

 

 

 

CLASSIC III AND IIID

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Lincoln Electric 10072, 10061, 10033, 10156 manual Welder Troubleshooting