Lincoln Electric CV-655 - Manual (Page 25)

CV-655
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
E-2 TROUBLESHOOTING E-2
Observe all Safety Guidelines detailed througout this manual
PROBLEMS
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
Input contactor (CR1) chatters.
Machine input contactor does not
operate.
Machine input contactor operates,
but no output when trying to weld.
1. Faulty input contactor (CR1).
2. Low line voltage.
1. Make sure the proper three-
phase input power is applied to
the CV655 machine.
2. The input contactor may be
faulty.
3. The power switch (SW1) may be
faulty.
4. The pilot transformer may be
faulty.
1. Electrode or work cables may be
loose or broken.
2. Firing P.C. board is not connected
or is faulty. See PC board LED
information.
4. Trigger circuit may not be working.
Place Output Terminals Switch to
the ON position, or place a jumper
wire across #2 and #4 on the ter-
minal strip. LED 6 on the control
PC board should go ON. If it does
not light check for opens in the #2
and #4 circuit. See wiring dia-
gram. If LED 6 does light the con-
trol board may be faulty.
5. If the thermal protection light is
ON the machine is overheated.
The choke or secondary ther-
mostats may be open. Make
sure the fan is operating and
remove the cause of the over-
heating problem. See PC board
LED information.
If all recommended possible areas
of misadjustments have been
checked and the problem persists,
contact your local Lincoln
Authorized Field Service Facility.