Lincoln Electric POWER MIG SVM170-A Service Manual page 68

F-28
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)
FIGURE F.9 — PLUG J1 LOCATION ON CONTROL PC BOARD.
TEST PROCEDURE
NOTE: POLARITY MUST BE OBSERVED
FOR THESE TESTS.
Test for Correct Wire Drive Motor Armature
Voltage
1. Disconnect main input power to the
machine.
2. Open the side panels and remove the
tool tray using a 5/16 in. nutdriver.
TROUBLESHOOTING AND REPAIR
POWER MIG 255C
J6
J6
J5
J5
J3
J3
J8
J8
B
B
(4J1)
(4J1)
J1
J1
W
W
(2J1)
(2J1)
#206B #206B
(1J1) (1J1)
J4
J4
J2
J2
3. Locate plug J1 on the control PC board.
See Figure F.9.
4. Locate the following leads on plug J1:
LEAD
W
5. Connect the main power to the
machine.
#555
#555
(6J1)
(6J1)
#515B
#515B
(5J1)
(5J1)
PLUG
LOCATION
B 4J1
2J1
F-28