Troubleshooting & repair, Chopper module function test (continued) – Lincoln Electric VANTAGE 400 User Manual
Page 111
CHOPPER MODULE FUNCTION TEST (CONTINUED)
TEST PROCEDURE (CONTINUED)
13. If about 58 VDC is present at chopper module
terminals B2+ to B3-, and B5+ to B6-, but not
at the output terminals, there is a problem
between the chopper module and one of the
output terminals. Check for damaged conduc-
tors or faulty connections, on leads W7, W8,
W9, and W10. Also check the shunt, the
choke, and the connections at the back of the
output terminals. See the wiring diagram.
14. If the voltage at terminals B2+ to B3-, and B5+
to B6- of the Chopper module is significantly
higher than 58 VDC, check for an open R4
load resistor. See the Control Inner-
Connection diagram. Also check for damaged
conductors or faulty connections at leads #302
and #302. See wiring diagram.
15. If the voltage at terminals B2+ to B3-, and B5+
to B6- of the chopper module is very low, or not
present, use the frequency counter to check
for the presents of a 20 kHZ PWM signal
between leads #23 +and #25-, where they con-
nect to the chopper module PC board.
16. If the 20 kHz signal is present, the chopper
module is defective. Replace.
17. If the 20 kHz signal is not present, perform the
Weld Control Board PWM Gate Signal Test.
18. If the weld control board is producing a PWM
gate signal, check th e#23 and #25 leads for
damaged conductors and faulty connections
between the control PC board and the chopper
module.
19. If testing is complete, Perform the Case Cover
Replacement procedure.
TROUBLESHOOTING & REPAIR
F-63
F-63
VANTAGE® 400