Troubleshooting And Repair - Lincoln Electric POWER FEED 10M SINGLE/DUAL SVM172-A Service Manual

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TROUBLESHOOTING AND REPAIR

TEST PROCEDURE
1. Remove input power from the wire
feeder unit.
2. Using the 3/8 in. nut driver, remove the
cover from the wire feeder.
3. Locate plug J84 on the feedhead
board. Refer to Figure F.2. Do
NOT remove the plug from the
feedhead board.
4. Apply the correct input power (from the
Power Wave 455 control cable) to
the wire feeder unit and check for
approximately 5VDC from (red wire)
positive to (black wire) negative.
This is the supply voltage from
feedhead board to the tach
feedback unit. If the 5VDC is
missing or not correct, the feedhead
board may be faulty. Also check for
loose or faulty wires and
connections.
TACH FEEDBACK TEST
(continued)
FIGURE F.2 – TACH FEEDBACK TEST.
Black
RED
BLUE
J84
5. With the gun trigger activated and the
6. Remove input power from the wire
7. Install the wire feeder cover with the
POWER FEED 10M SINGLE/DUAL
WIRE FEED
CONTROL BD.
motor running, check the feedback
voltage at plug J84 (blue wire)
positive to (black wire) negative.
Normal feedback voltage is
approximately 2 VDC. If the correct
supply voltage is present and the
feedback voltage is mssing, the tach
unit may be faulty. With the motor
NOT running, the feedback voltage
may be either 0 or 2 VDC
depending upon where the motor
stopped.
feeder unit.
3/8 in. nut driver.
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