The arc is unstable and or “hunting, Troubleshooting and repair, Caution – Lincoln Electric POWER MIG SVM157-A User Manual
Page 43: Troubleshooting guide
TROUBLESHOOTING AND REPAIR
Observe Safety Guidelines
detailed in the beginning of this manual.
Troubleshooting Guide –
See Wiring Diagrams for location of specified
components and for troubleshooting of specific circuits.
F-9
F-9
POWER MIG 200
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the
Lincoln Electric Service Department for technical troubleshooting assistance before you proceed. Call 1-800-833-9353
CAUTION
WELDING PROBLEMS
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
Poor arc striking with electrode
sticking or blasting off.
The arc is unstable and or “hunting”
1. Make sure the settings for wire
feed speed and voltage are cor-
rect for the process being used.
2. Make certain the gas shielding is
correct for the process being
used.
3. Make sure the machine’s recon-
nect panel is configured properly
for the input voltage being
applied.
1. Check for a worn or melted con-
tact tip.
2. Check for loose or faulty connec-
tions on the work and gun cables.
3. Make sure the electrode polarity
is correct for the welding process
being used.
4. Check for rusted or dirty electrode
wire.
5. Make sure the machine’s settings
and shielding gas are correct for
the process being used .
1. The output capacitors may be faulty.
Check for loose connections at the
capacitors. Also check for leaky
capacitors. Replace if necessary.
WARNING: The liquid electrolyte in
these capacitors is toxic. Avoid con-
tact with any portion of your body.
2. Perform the Output Diode Rectifier
1. Check for loose or faulty connections
at the output terminals, choke, output
capacitors, output selector switch,
output contactor, and all heavy cur-
rent carrying leads. See the wiring
diagram.
2. Check the output selector switch for
proper operation and good connec-
tions.
3. The output capacitors may be faulty.
Check for loose connections at the
capacitors. Also check for leaky
capacitors. Replace if necessary.
WARNING: The liquid electrolyte in
these capacitors is toxic. Avoid con-
tact with any portion of your body.
4. Perform the Output Bridge Rectifier