Lincoln Electric SVM188-A Service Manual page 60

F-20
1
2 (256)
(291) 8
J2
(290) 7
5 (231)
(255) 6
J3
1 (210)
(222)12
1
LED2
J1
PROCEDURE
WARNING
ELECTRIC SHOCK
• Do not touch electrically hot parts.
1. Turn the POWER Switch ON. LEDs 1 and 3 should
turn ON.
2. If LED 1 does not come ON, but the Power Light
is ON, check for 120vac at J2 (pin 6 and pin 2).
See the Wiring Diagram.
• If the Power Light is not ON, perform the Control
Transformer Voltage Test and check the Power
Switch and associated wiring.
3. If LED 3 does not come ON but LED4 is ON, the
DC-600 has shut down due to over-current or a
fault in the control leads (75,76 & 77).
• Disconnect any control cables, welding leads or
jumpers from the terminal strips (TS1& TS2).
TROUBLESHOOTING AND REPAIR
CONTROL BOARD TEST (continued)
FIGURE F.7 CONTROL BOARD
LED3
LED1
LED4
LED6
can kill.
DC-600
LED5
DC600 CONTROL G3409-1
4. If the machine stays ON and all LEDs are correct,
the problem is external to the machine. If LED4 still
comes ON:
• Check the Output Studs and associated wiring for
a 'shorted' or 'grounded' condition.
• Check for grounds in the control circuit (Output
Control, Local/Remote Switch & TS1).
• Control Board may be defective.
NOTE: LED 4 should be OFF except in a "shutdown"
condition. If ON and machine is still function-
ing, replace the Control Board.
5. LED 5 indicates a signal to the Firing Board and
should vary in brilliance as the Output Control is
adjusted. If LED 5 is not ON or does not change:
• Make certain that LED 6 is ON. The Output
Terminal Switch the Local/Remote Switch must
be in "LOCAL" position and the Mode Switch in
CV. If switches are set properly and functional, the
Control Board may be defective.
6. LED 6 indicates a signal from the Firing Board that
the DC-600 is "triggered". If not ON, perform the
Internal Trigger Test.
F-20