Lincoln Electric NA-5N Service Manual page 62

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Observe all Safety Guidelines detailed throughout this manual
PROBLEMS
(SYMPTOMS)
NA-5 units above code 8300 with
"cold starting".
The wire feeds up instead of down
when the start button is pressed.
The wire inches up and down prop-
erly.
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)
WIRE FEEDING PROBLEMS
1. Make sure the electrode wire is
fed into the welding tip.
2. Check the 1/8 amp fuse on the
voltage board. Replace if faulty.
3. Make sure electrode polarity is
correct and the same as the #67
and #21 leads at terminal strip
(TS1). See wiring diagram.
4. Make sure the welding power
source is producing welding arc
voltage.
CAUTION
NA-5
RECOMMENDED
COURSE OF ACTION
1. Jumper the #2 and #4 leads at
the Lincoln CV power source.
Open circuit voltage should be
present at both the power source
and at the ACTUAL voltmeter
reading on the NA-5. If open cir-
cuit voltage is present at the
power source but NOT at the NA-
5 ACTUAL voltmeter reading per-
form the #21-#67 External resis-
tance Test.
2. With the start button pressed light
7K should be lit. If it is not the
logic board may be faulty.
3. Check contactor relay 3CR.
Leads #2 and #4 are closed by
relay 3CR. Make sure the relay is
functiioning properly.
4. Check the control cable between
the power source and the NA-5
control unit. See wiring diagram.
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