Lincoln Electric NA-3 Service Manual page 79

F-14
Troubleshooting Guide –
of specified components and when troubleshooting specific circuits.
PROBLEMS
(SYMPTOMS)
The welding does not stop when the
"Stop" switch is pressed.
The burnback time cannot be set
properly.
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 AND REPAIR
See the Wiring Diagrams Section for location
POSSIBLE AREAS OF
MISADJUSTMENT(S)
FUNCTION PROBLEMS (Continued)
1. If a crater board is installed,
remove and replace with the
jumper plug. If the problem is
resolved, the crater board may
be faulty.
1. The logic board may be faulty.
CAUTION
NA-3 AND NA-4
Observe Safety Guidelines
detailed at the beginning of this manual.
RECOMMENDED
COURSE OF ACTION
1. While pressing the "Stop"
switch, observe light 2C on the
logic board. If light 2C is lit,
the logic board may be faulty.
2. If light 2C does not light when
the "Stop" switch is pressed,
the switch or associated leads
may be faulty. See wiring
diagram.
1. Replace the logic board.
F-14