Wire Drive Motor And Tachometer Feedback Test - Lincoln Electric POWER MIG SVM165-A Service Manual

F-28
WIRE DRIVE MOTOR AND TACHOMETER FEEDBACK TEST (continued)
FIGURE F. 8 – PLUG J83 AND J84 LOCATIONS ON FEEDER BOARD
G3884
J83
J84
TEST PROCEDURE
NOTE: POLARITY MUST BE OBSERVED FOR
THESE TESTS.
TEST FOR CORRECT WIRE DRIVE MOTOR ARMA-
TURE VOLTAGE
1. Disconnect main input power to the machine.
2. Open the side panels and remove the tool tray
using a 5/16" nut Driver.
3. Locate the following leads on plug J83:
4. Locate leads 831(black) and 832(white) on plug
J83.
TROUBLESHOOTING & REPAIR
B
MOTOR / GEARBOX
2.6 VDC @ 50 IN/MIN
27.4 VDC @ 700 IN/MIN
8 SECOND AVERAGE CURRENT
LIMIT = 3.5A
(LIMIT IS SOFTWARE SET)
FROM LEAD TO LEAD
831 + 832 -
(1J83) (2J83)
POWER MIG 350MP
1
2
PWM CONTROLLED
6.5 VDC WHEN GAS
LOCATED ON
FLOWING COIL
CASE BACK
MEASURES 21 OHMS
12 VDC CO IL
W
ACCESS THIS CONNECTOR
BY REMOVING THE WIRE
TACH DRIVE ASSEMBLY
R
R 1
U
U 2
B
B 3
4
J84
844 847
832
831
841
5. Connect the main power to the machine.
7. Make the following voltage tests. From the table
below.
8. Carefully insert the meter probes into the back of
each Molex plug pin cavity to perform the test.
9. Turn the machine ON and pull the gun trigger to
conduct this voltage test.
EXPECTED VOLTAGE
2.5-27 VDC
(varies depending
on wire feed speed)
F-28
TOROID
MOTOR +
1J83
831
MOTOR -
832 2J83
GAS SOLENOID +
833 3J83
GAS SOLENOID -
4J83
834
TOROID
5VDC TACH SUPPLY
841 1J84
TACH SIGNAL
847 7J84
TACH COM
4J84
844
MEASURE B TO U
120 Hz @ 50 IN/MIN
1.6 kHz@700 IN/MIN
J83