The welding arc is variable and sluggish, Troubleshooting & repair, Caution – Lincoln Electric IDEALARC SVM 122-A User Manual
Page 58
TROUBLESHOOTING & REPAIR
F-14
F-14
LINCOLN
®
ELECTRIC
IDEALARC DC-400
TROUBLESHOOTING GUIDE
Observe Safety Guidelines
detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
WELDING PROBLEMS
The Arc Force control (R5) has no
effect on the arc.
1. The Arc Force control is active
only in the Stick Mode.
2. The effect of the Arc Force con-
trol will be less noticeable at
high welding currents. Weld at
low currents (less than 150
amps) and check the Arc Force
control function.
1. Check the Arc Force control
potentiometer (R5) for correct
resistance and proper opera-
tion. Normal resistanace is
10,000 ohms.
2. Check the continuity of leads
#204, #208, and #209 from the
Arc Force control to the control
board.
3.
The control board may be
faulty. Replace.
The welding arc is variable and
sluggish.
1. Check the input voltage at the
DC-400, making sure the cor-
rect voltage and all three
phases are being applied to the
machine.
2. Make sure welding process is
correct for machine settings.
3. Check welding cables for loose
or faulty connections. Also
make sure cables are sized cor-
rectly for welding current.
1. Check the welding Mode switch
(S4), the microswitches, and the
associated wiring.
2. Perform the SCR/Diode Rec-
3. Perform the Main Transformer
4. The control board may be faulty.
Replace.
CAUTION
If for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-
tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call
216-383-2531 or 1-800-833-9353.