Lincoln Electric RED-D-ARC DX450 Service Manual page 52

F-8
Observe Safety Guidelines detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
The machine will weld but the
welding arc is "COLD". The
engine runs normally and the aux-
iliary power is normal.
(continued)
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)
OUTPUT PROBLEMS
CAUTION
If the maximum weld output can-
not be obtained, check for dam-
aged conductors and lose or dam-
aged connections at the large cur-
rent carrying conductors that con-
nect the stator, output rectifier,
chopper modules, choke, shunt,
and output terminals. See the
Wiring Diagram.
If all these connections are good
perform the following:
Rotor Voltage Test
Stator Voltage Test
Output Rectifier Test
Chopper Module Resistance
Test
Control Potentiometer and
Mode Resistance Test
Remote Receptacle Resistance
Test
Replace the Control P.C. Board.
DX450
RECOMMENDED
COURSE OF ACTION
F-8