Lincoln Electric IM526-B Welding System User Manual


 
16
TEST PROCEDURES
Step
1A
1B
2
3A
3B
Next
Test
Step
1B
2
3A
3B
4
and
5
Test
Output pilot circuit
(set S4 on)
Protection PC
board output (set
S4 on)
Static capacitor
balance (set S4
off)
380 VAC input
and higher test
Dynamic capaci-
tor balance (set
S4 on)
380 VAC input
and higher test
Repair Action
Replace Power
and Control PC
Boards
Replace
Protection PC
Board
Check
223A to 210
302 (pos) to 275D (neg)
313 (neg) to 311 (pos)
Compare voltage across
terminals 9 & 12 of each
Switch PC Board.
575 VAC -- 407 VDC
460 VAC -- 325 VDC
440 VAC -- 311 VDC
415 VAC -- 293 VDC
380 VAC -- 269 VDC
575 VAC only - compare
voltage across 9A & 13
and 13 & 12A; then, 9B &
15 and 15 & 12B
Connect as in step 3A.
Same voltages as above.
Test
Result
24 VAC
0 VAC
15 VDC
0 VDC
<1 VDC
>5 VDC
<25 VDC
difference
between
readings
>25 VDC
difference
<25 VDC
>25 VDC
Conclusion
Fan thermostat, choke
thermostat, T1 trans-
former and S4 all OK.
Check above compo-
nents.
T1 and 15V power sup-
ply OK.
Check T1 and Power PC
Board.
Protection PC Board OK
C1, C2, R1, R9 - OK
(575 VAC machine C14,
C15 - OK)
Check above compo-
nents.
OK
Power PC Board or
Switch PC Boards are
damaged.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, con-
tact your local Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION