Troubleshooting & repair – Lincoln Electric INVERTEC SVM101-B User Manual

Page 72

V300-I

TROUBLESHOOTING & REPAIR

11. If 15 VDC is present at step 7, test Capacitor volt-

ages using leads shown in Figure F.19.

If voltage does not match table, check reconnect
switches for proper operation and proper position
for voltage applied. Perform Capacitor Balance
Tests.

F-42

FIG. F.19 - OVERVOLTAGE PROTECTION DC TRIGGER CIRCUIT

OVERVOLTAGE PROTECTION DC TRIGGER CIRCUIT TEST (cont.)

THESE LEADS
ARE USED FOR
MONITORING
CAPACITOR
VOLTAGES

SEE TABLE 1
BELOW

#311

#313

1J8

3J8

TABLE 1:INPUT VOLTS FOR
460 VOLTS AC

LEADS

NORMAL

52-53

51-53

14-53

14-52

325 VDC

14-15 VDC

315 VDC

OPTOCOUPLER
DEPENDENT ON
PROTECTION BOARD

IF AC TRIGGER
CIRCUIT IS GOOD,
#301 LEAD
IS TAKEN TO
CIRCUIT COMMON
#275D

POWER
BOARD

CONTROL
BOARD

+15 VDC

4J1

5J1

6J6

1J6

1J14

2J14

PROTECTION
BOARD

#302

#275D

(+)

(-)

#301

#305