Lincoln Electric IDEALARC DC-1500 Service Manual page 60

F-26
FIRING BOARD TEST PROCEDURE (continued)
L 9 L 6 L 5
1 2 P I N G 1 5 8 7 - 1 L 8 L 7 L 1 L 3 L 4 9 P I N L 2
G1587-1
TEST PROCEDURE FOR NORMAL
FIRING BOARD OPERATION
1. Disconnect main AC input power to the
machine.
2. Remove the top left case side. Locate the
Firing Board. See Figure F.7.
3. Visually inspect the Firing Board for loose or
faulty connections.
4. Reconnect the input power and turn the
DC-1500 on.
5. Locate LEDs 7, 8, and 9 on the Firing Board.
See Figure F.6. Each LED should be ON and
equally bright. Refer to next page to check
LED operation.
6. Connect a jumper wire from terminal #2 to ter-
minal #4 on the terminal strip. These can be
accessed through the Front Panel Assembly
door. See Figure F.6.
TROUBLESHOOTING AND REPAIR
FIGURE F.6 – FIRING BOARD
L7
12 PIN
L8
L9
IDEALARC® DC-1500
L2
L1
9 PIN
L3
L4
L5
L6
WARNING
JUMPERING LEADS 2 AND 4 ELECTRICALLY
ENERGIZES MACHINE'S OUTPUT TERMI-
NALS. DO NOT TOUCH ELECTRICALLY HOT
COMPONENTS.
_______________________________________________
7. Locate LEDs 1 thru 6. Each LED should glow
with equal brightness. See Figure F.6.
NOTE: LEDs 1 through 6 indicate that the gate fir-
ing signals are being generated to send to
each of the output SCRs.
8. Set the output control switch (SW4) in the
"Output Control at DC-1500" position.
9. Set the welding mode switch (SW5) in either of
the "CV" positions.
F-26