Lincoln Electric Fleet 650 Service Manual page 55

LINCOLN ELECTRIC
The shunt used in this machine will produce 50 millivolts at a load of 400 amps or 8 amps per
millivolt.
To calculate the correct millivolt signal for a given load, you divide the number of amps displayed on
the ammeter by 8.
Example: If your ammeter reads 75, (75/8= 9.4). If the shunt is working correctly and the wiring
between the shunt and the weld control board is in good condition, the meter connected at the
weld control board should be reading about 9.4 millivolts.
13. If the millivolt reading is incorrect, check the wiring between the shunt and the weld control board
for damage, grounds and faulty connections. If the wiring is good, the shunt and lead assembly is
faulty and should be replaced.
14. Perform the Case Cover Replacement Procedure.
Figure F.20 – Weld control board plug locations
Fleet™ 650 Service Manual
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