Lincoln Electric IM904 Welder User Manual


 
E-4
TROUBLESHOOTING
E-4
INVERTEC STT II (CE)
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
Observe Safety Guidelines detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
No output or reduced output the first
time power is applied to the
machine.
Machine loses output while welding.
The thermal indicator light is lit.
Normal welding output returns after
about 10 minutes.
Machine has low OCV, and loses
output while attempting to weld.
POSSIBLE
CAUSE
1. Check input voltages, fuses and
input voltage reconnect proce-
dures. See Installation section.
2. If high input voltage (380VAC or
higher) is applied, the capacitors
may need conditioning. Let the
unloaded machine idle for 30
minutes.
1. Check to make sure the fans are
running and operating correctly.
2. Welding application may exceed
recommended duty cycle.
3. Dirt and dust may have clogged
the cooling channels. Blow out
unit with clean, dry compressed
air.
4. Air intake and exhaust louvers
may be blocked due to inade-
quate clearance around machine.
1. Check for faulty connection on
plug J1 on Control Board and
plug J1 on Current Sense Board.
2. Check for faulty Current Sense
Board.
RECOMMENDED
COURSE OF ACTION
If all recommended possible areas
of misadjustment have been
checked and the problem persists,
Contact your local Lincoln
Authorized Field Service
Facility.
OUTPUT PROBLEMS