Lincoln Electric INVERTEC V300-PRO SVM105-B Service Manual page 67

F-37
OVERCURRENT PROTECTION CURRENT TRIGGER TEST (cont.)
J5
6. Turn main power OFF.
7. Perform Input Filter
Procedure detailed in this section.
Test resistance of the Black and White leads from
1J3 and 2J3 to the shunt. See Figure F.14.
a. If zero ohms resistance (continuity) is shown,
test is OK.
b. If resistance of any value is shown, check wire
and connections.
FIGURE F.15 - OVERCURRENT PROTECTION CURRENT TRIGGER CIRCUIT.
TROUBLESHOOTING & REPAIR
FIGURE F.14 - CONTROL BOARD TEST POINTS
CONTROL
G2527
Capacitor Discharge
302
6J1
CONTROL
BOARD
1J3
BLACK
L3
400 AMP
CHOKE
SHUNT
V300-PRO
J1
J4
J2
NOTE: On earlier codes the terminals on the shunt
leads were crimped but not soldered. Corrosion may
cause inaccurate current readings. Cleaning and sol-
dering the terminals to the leads may eliminate that
problem.
If tests for steps 5, 7, are OK and the machine contin-
ues to experience the problem, the Control Board
should be replaced.
275D
1J1
2J3
WHITE
F-37
2J3 (White)
J3
1J3 (Black)
(-) OUTPUT
TERMINAL