Lincoln Electric IDEALARC DC-1500 Service Manual page 69

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CONTROL BOARD TEST PROCEDURE (continued)
IF LED 3 (24 VDC Internal Supply) does not
light when the Start Button is depressed (but
LED 1 does light).
The Fault Protection Relay (2CR) is not receiving
supply voltage (24 VDC) and the Input Contactor
(1CR) will not stay closed. Check to see if LED 4
lights or "flickers" when the Start Button is held in.
If LED 4 (Fault) lights,
1. There may be a "short" at the welder output
terminals or the remote control circuit (leads
#73, #74, # 75, #76 and #77) may be shorted
to the negative welding voltage. Check the
weld output terminals and associated leads
and also the remote control circuitry. See
wiring diagram.
2. If the above procedures do not reveal the prob-
lem, then the Control board may be faulty-
Replace.
TROUBLESHOOTING AND REPAIR
IDEALARC® DC-1500
IF LED 5 (Control Signal) does not light and
varies in brightness when #2 and #4 are
jumpered together, while the Output Control
Potentiometer is rotated .
The Control Board may be faulty- Replace.
NOTE: The Weld Mode Switch (SW5) must be in
the CV position and the Output Control
Switch (SW3) in the "Output Control at
DC-1500" position. Also check the Output
Control Potentiometer and associated cir-
cuitry.
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