Lincoln Electric 11141 Service Manual page 89

F-43
AUXILIARY TRANSFORMER TEST (continued)
OUTPUT LOAD CURRENT
300
250
200
150
100
8. Check the feedback voltage from the current
transducer using a resistive load bank and with
the POWER WAVE
Mode 200 is a constant current test mode.
This mode can be accessed using a wire feed-
er placed in mode 200 or a laptop computer
and the appropriate software. Apply the grid
load across the output of the POWER WAVE
355M/405M. Set machine output to 300 amps
and enable WELD TERMINALS. Adjust the
grid load to obtain 300 amps on the external
ammeter and check feedback voltages per
Table F.6.
A. Pin 1 (lead 801) to Pin 6 (lead 806) should
read 2.4 VDC (machine loaded to 300
amps).
9. If for any reason the machine cannot be loaded
to 300 amps, Table F.6. shows what feedback
voltage is produced at various current loads.
TROUBLESHOOTING AND REPAIR
TABLE F.6
355M/405M in mode 200.
®
POWER WAVE
EXPECTED TRANSDUCER FEEDBACK
VOLTAGE
10. If the correct supply voltages are applied to the
current transducer, and with the machine
loaded, the feedback voltage is missing or not
correct the current transducer may be faulty.
Before replacing the current transducer, check
the leads and plugs between the control board
(J8) and the current transducer (J90). See The
Wiring Diagram. For access to plug J90 and
®
the current transducer refer to: Current
Transducer Removal and Replacement
Procedure.
11. Remove input power to the POWER WAVE
355M/405M.
12. Replace the control box top and any cable ties
previously removed.
13. Install the case wraparound cover using the
5/16" nut driver.
® 355M/405M
F-43
2.4
2.0
1.6
1.2
0.8
®