Lincoln Electric SQUARE WAVE IM687 Operator's Manual page 22

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Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
Machine output is intermittently lost.
Gas flow and high frequency are
also interrupted.
Arc "Flutters" when TIG welding.
Arc "Pulsates" when AC TIG
welding.
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.
APR96
TROUBLESHOOTING
POSSIBLE AREAS OF
MISADJUSTMENTS
TIG MODE PROBLEMS
1. Problem may be caused by high
frequency interference. Make
sure that the machine is ground-
ed properly according to the
installation instructions. If there
are other high frequency
sources in the area, make cer-
tain that they are grounded
properly.
2. Check Amptrol for proper opera-
tion and loose connections.
3. Check for proper input voltage
and proper voltage reconnec-
tion.
1. Tungsten electrode may be too
large in diameter for the current
setting.
2. Tungsten not "sharp" when
welding in DC - mode.
3. Gas shielding may be insuffi-
cient. Increase gas flow; reduce
tungsten stickout beyond gas
cup.
4. Check for contaminated gas or
leaks in the gas line, torch, or
connections
5. If a helium blend is used as a
shielding gas, then reduce the
percentage of helium.
1. Micro Switch mounted on
Polarity Switch is not opening in
"AC" mode.
CAUTION
SQUARE WAVE TIG 175 PRO
RECOMMENDED
COURSE OF ACTION
Contact your Local Lincoln Authorized
Field Service Facility for technical
troubleshooting assistance.
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