E-5
TROUBLESHOOTING
E-5
SQUARE WAVE TIG 275
Observe all Safety Guidelines detailed throughout this manual
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.
CAUTION
TIG WELDING TROUBLE
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENTS(S)
RECOMMENDED
COURSE OF ACTION
Machine does not respond (no gas
flow, no high frequency, no open cir-
cuit voltage) when Arc Start Switch
or Amptrol is pressed. Thermal light
is not lit.
No gas or water flow (with optional
water solenoid) when Arc Start
Switch or Amptrol is pressed in the
TIG Weld Mode.
No High Frequency.
1. Defective Arc Start Switch or
Amptrol. Check for continuity
between pins D and E on cable
connector when Arc Start Switch
or Amptrol is pressed.
2. The Control PC Board may be
faulty. See PC Board
Troubleshooting Procedures.
1. Gas supply is empty or not turned
on.
2. Pinched, disconnected, or leaking
gas or water hose.
3. Gas and/or water lines or sole-
noids are blocked with dirt. Clean
out and use filters to prevent reoc-
currence.
4. Defective gas and/or water sole-
noid. Check and replace.
5. The Control PC Board may be
faulty. See PC Board
Troubleshooting Procedures.
1. Spark gap is too large. Reset gap
per Periodic Maintenance Section
instructions.
2. Check gas solenoid operation. If it
is not working, check 115V circuit
from Main Transformer (T1).
Check Fuse (F1) on European
models only.
3. Defective high voltage transformer
(T2). Check and replace.
4. One or more of the following
components may be open: R5 or
C6. Check and replace.
5. The Control PC Board may be
faulty. See PC Board
Troubleshooting Procedures.
Contact your Local Lincoln Authorized
Field Service Facility for technical
troubleshooting assistance.
