Lincoln Electric LN-8 SVM132-A Service Manual page 55

F-5
Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
The wire feeds when the gun trig-
ger is activated but there is no arc
voltage.
The wire continues to feed with the
gun trigger open, and the wire is
electrically "hot". The interlock
switch is in the "off" position.
With the interlock switch (S2) in the
"ON" postion, the wire feed stops
when the gun trigger is released.
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 1-800-833-9353.
TROUBLESHOOTING AND REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
FUNCTION PROBLEMS (Continued)
1. Check the welding cables for
loose or faulty connections.
2. Put a jumper wire from #2 to #4
on the power source terminal
strip. (machines with 14 pin
amphenols pin C to pin D). If the
arc voltage is not present at the
output terminals, the power
source is faulty. If the arc volt-
age IS present, the problem is in
the wire feeder or control cable.
3. Check the continuity of leads #2
and #4 through the control cable.
Replace if "open".
4. The welding gun may be faulty.
Check or replace.
1. Disconnect the gun trigger cable.
If the problem is solved, the gun
trigger or cable is faulty. Repair
or replace.
1. Check leads #529 and #528 for
loose or faulty connections
between the 2CR reed switch
and the control board and motor
thermal circuit breaker. See
wiring diagram.
CAUTION
RECOMMENDED
COURSE OF ACTION
1. The 1CR relay, located on the
power board, may be faulty.
Check or replace. Note: The
relay may operate but the indi-
vidual contacts may not be func-
tioning properly.
2. If a burnback kit is installed,
remove and install the jumper
plug. If the problem is solved,
the burnback kit is faulty.
3. Check the #2 and #4 leads in the
LN-8 wiring harness for loose or
faulty connections. See wiring
diagram.
1. The 1CR relay may be stuck
closed. Perform the 1CR Relay
Test.
2. Check the relay board. Replace
if faulty.
1. The 2CR reed switch may be
faulty. Check to see if it closes
when welding.
2. Check the interlock switch (S2)
for proper operation.
3. Check the continuity (zero ohms)
of leads #523 and #536 between
the interlock switch (S2) and the
relay board. See wiring diagram.
4. The relay board may be faulty.
LN-8
F-5