Lincoln Electric NA-5N Service Manual page 70

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Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
At the end of the weld the crater light
does NOT light.
At the end of the weld the crater
timer does not time out. The unit
stays in the crater mode.
No burnback/retract occurs at the
end of the weld.
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 216-383-2531 or 1-800-833-9353.
TROUBLESHOOTING & REPAIR
POSSIBLE AREAS OF
MISADJUSTMENTS(S)
MODE FUNCTION PROBLEMS
1. Make sure the crater option is
installed properly in the NA-5.
2. Make sure the crater timer is set
for a time greater than zero sec-
onds.
3. The crater option and or timer
board may be faulty. Replace.
4. The logic board may be faulty.
1. Replace the crater option board
with the jumper plug. Set the
burnback timer for any time
greater than zero seconds. If the
unit then stops after the weld and
burnback time, the crater timer
board may be faulty. Replace.
2. If the unit does not stop the pro-
cedure board may be faulty.
1. Make sure the burnback timer is
set for a time greater than zero
ohms.
2. Be sure the jumper leads or dip
switches on the logic board are
comfigured correctly for the burn-
back/retract desired. See wiring
diagram.
3. The burnback timer module may
be faulty. Replace.
4. The procedure board may be
faulty.
CAUTION
NA-5
RECOMMENDED
COURSE OF ACTION
1. Check the lead harness between
the crater boards and the proce-
dure board for loose or faulty con-
nections. See wiring diagram.
1. Check the lead harness between
the crater boards and the proce-
dure board for loose or faulty con-
nections. See wiring diagram.
1. Check the lead harness between
the burnback module and the pro-
cedure board for loose or faulty
connections.
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