Lincoln Electric SQUARE WAVE TIG 355 Service Manual page 64

F-12
Observe Safety Guidelines detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
When using Crater Fill the arc goes
out before the final crater fill current
level is reached.
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)
FUNCTION PROBLEMS
1. The Crater Fill % Peak Current
control may be set too low for the
tungsten being used. Increase
the Crater Fill % Peak Current
control until the final crater fill
current is within the tungsten's
operating range.
2. If using the Pulser in conjunction
with the
Background % Peak Current
may be too low for the tungsten
as the current is downsloping in
crater fill. The best solution is to
increase the Background %
Peak Current level.
3. If welding
"Continuous" high frequency.
The high frequency will stabilize
the arc as the current goes down.
CAUTION
SQUARE WAVE TIG 355
1. Check the Crater Fill Fade Out
control potentiometer for correct
resistance and proper opera-
tion.
2. The control board may be faulty.
Replace.
Crater Fill, the
with AC, use
F-12
RECOMMENDED
COURSE OF ACTION