Lincoln Electric LN-25 PRO DUAL POWER Service Manual page 56

F-6
Observe Safety Guidelines detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
Variable or "hunting" arc.
When the trigger is pulled, the wire
feeds slowly.
(Digital display models)
Poor arc starts with sticking or "
Blast-offs", weld porosity, narrow or
ropy looking beads.
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 1-888-935-3877.
TROUBLESHOOTING AND REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
OUTPUT PROBLEMS
1. Wrong size, worn or melted tip.
2. Worn work cable or poor con-
nection.
3. Wrong polarity'
4. The gas nozzle is extended
beyond the contact tip or the
wire stickout is too long.
5. Poor gas shielding on process-
es requiring gas.
The Run-in switch is "ON"
Improper procedures or techniques. See "Gas metal arc welding guide"
CAUTION
LN-25™ PRO DUAL POWER
RECOMMENDED
COURSE OF ACTION
1. Replace the tip.
2. Verify all the work and elec-
trode connections are tight and
in good condition Clean if nec-
essary and replace.
3. Adjust polarity to recommend-
ed procedure verify DIP switch
7 setting matches the elec-
trode polarity.
4. Adjust the gas nozzle and
shorten the stickout to 1/2 to
3/4 inches.
5. Check gas flow and mixture.
Remove or block sources of
drafts. Perform the Gas
Solenoid Test, replace if nec-
essary.
Turn the run-in switch to the "OFF"
position.
(GS-100)
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