Lincoln Electric PRECISION TIG 225 Operator's Manual page 32

E-5
PROBLEMS
(SYMPTOMS)
Black areas along weld bead.
Weak high frequency - machine has
normal welding output.
High frequency "spark" is present at
tungsten electrode, but operator is
unable to establish a welding arc.
Machine has normal open circuit
voltage (refer to
Specifications in the Installation
Chapter).
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.
TROUBLESHOOTING
Observe all Safety Guidelines detailed throughout this manual
POSSIBLE
TIG MODE PROBLEMS
1. Clean any oily or organic contam-
ination from the work piece.
2. Tungsten electrode may be cont-
aminated. Replace or sharpen.
3. Check for contaminated gas or
leaks in the gas line, torch, or
connections.
4. Gas shielding may be insufficient.
Increase gas flow; reduce tung-
sten stickout beyond gas cup.
1. Check for loose or faulty connec-
tions at the torch and/or welding
cables.
2. The gas shielding may be insuffi-
cient. Increase gas flow: reduce
tungsten stickout beyond the gas
cup.
3. Check spark gap operation and
setting. Normal is (0.020"). Refer
to Maintenance section of this
report.
4. The work and electrode cables
may be in poor condition allowing
the high frequency to "leak off".
Use good quality cables with a
high natural rubber content, such
as Lincoln Stable Arc Cable.
Cables should be as short as pos-
sible.
1. The torch may be faulty. Check or
replace.
2. The current control may be set too
low.
Technical 3. The tungsten electrode may be
contaminated. Replace or sharp-
en.
4. The electrode may be too large for
the process.
5. If a helium blend is being used as
a shielding gas, then reduce the
percentage of helium.
6. Check the welding cables for
loose or faulty connections.
7. This may be a welding procedure
problem.
PRECISION TIG 225
CAUSE
If all recommended possible areas of
misadjustment have been checked
and the problem persists, Contact
your local Lincoln Authorized
Field Service Facility.
CAUTION
RECOMMENDED
COURSE OF ACTION
E-5