Lincoln Electric RANGER 3PHASE SVM207-A Service Manual page 48

F-10
Observe Safety Guidelines detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
The welding arc is "cold." Engine
runs normally (3700 RPM no load).
Auxiliary power is functioning nor-
mally.
Welding output is low with little
or no control. Auxiliary output is
also low.
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 1-888-935-3877.
TROUBLESHOOTING AND REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
WELDING PROBLEMS
1. Check for loose or faulty connec-
tions at the weld output terminals
and welding cable connections.
2. The welding cable may be too
long or coiled, causing an exces-
sive voltage drop.
1. Check the brushes for wear and
proper contact to the rotor slip
rings.
CAUTION
RANGER® 3 PHASE
RECOMMENDED
COURSE OF ACTION
1. Check for the correct open cir-
cuit voltage (OCV) at the welder
output terminals See
Machine Diagram. If the cor-
rect voltage is present at the
output terminals, then check for
loose connections on the heavy
current carrying leads inside the
RANGER® 8. See Wiring
Diagram.
2. If the OCV is low at the welder
output terminals, perform The
Engine Throttle Adjustment
Test.
3. Perform the Output Rectifier
Bridge Test.
4. Check for shorted or grounded
windings in the reactor and also
in the main stator. See Wiring
Diagram.
1. Make up a jumper to connect
the Field Test Point (FTP1) on
the PC Board to lead 219. The
connection can be made at the
board (J1,Pin5), or at the
Negative Exciter Brush. See
Figure F.4 and/or the Wiring
Diagram. If the output comes
up to full strength, the Control
Board is probably defective.
Replace.
2. Perform the Rotor Voltage
Test.
3. If Rotor Voltage Test is normal,
then preform the
Resistance Test.
4. If the Rotor Voltage Test is NOT
normal, perform the Auxiliary
and Field Winding Voltage
Test. The Printed Circuit Board
may be faulty. Replace
F-10
the
Rotor