Section IV. TROUBLESHOOTING
40. General
This section provides information useful in diagnosing and correcting unsatisfactory operature or failure of the
welding machine and its components. Each trouble symptom stated is followed by a list of probable causes of trouble.
The possible remedy recommended is described opposite the probable cause. Any trouble beyond the scope of
organizational maintenance shall be reported to direct support maintenance.
41. Welder Will Not Start (Starter Not Operating)
Probable cause
Possible remedy
Power circuit dead .....................................................................................Check voltage.
Broken power lead .....................................................................................Replace or repair.
Wrong voltage ...........................................................................................Check nameplate against power supply.
Incorrect connections to starter ..................................................................Check connections against wiring diagram (fig. 4).
Open power switch ....................................................................................Close switch.
Blown power source fuses..........................................................................Replace (refer to wiring data table 1).
Overload relay tripped ...............................................................................Allow welding machine to cool.
Remove cause of
overload.
Open circuit to starter button......................................................................Check connections against wiring diagram (fig. 4).
Mechanical obstruction on starter...............................................................Remove obstructions.
42. Starter Chatters
Probable cause
Possible remedy
Line leads too small ...................................................................................Install larger leads (refer to wiring data table 1).
Power supply inadequate ...........................................................................Report to proper authority.
Low line voltage .........................................................................................Report to proper authority.
Sticky operation .........................................................................................Replace starter (para 66).
43. Welder Will Not Start
Probable cause
Possible remedy
Wrong motor connections to starter ...........................................................Check connections against wiring diagram (fig. 4).
Wrong supply voltage ................................................................................Check nameplate and connections against power supply.
Report to proper authority.
Rotor stuck ................................................................................................Try turning by hand.
Power source line circuit single-phased......................................................Replace fuse. Report open line to proper authority.
Poor motor connections to starter .............................................................Tighten connections.
44. Starter Operates and Blows Fuse
Probable cause
Possible remedy
Power source fuse size too small ...............................................................Refer to wiring data table 1 for recommended fuse size.
Short circuit in motor connections ..............................................................Check starter and motor leads insulation for ground.
45. Welder Starts but Will Not Deliver Welding Current
Probable cause
Possible remedy
Wrong direction of rotation.........................................................................Refer to paragraph 26.
Brushes worn or missing; brush springs broken or .....................................Check that all brushes bear on commutator with sufficient
missing.
Brush connections loose ............................................................................Tighten connections (para 56).
Open field circuit........................................................................................Check connection to rheostat and to excitation brush studs
(fig. 56).
Welding terminal shorted ...........................................................................Electrode holder or welding cable may be grounded.
Brushes binding in holder...........................................................................Remove obstruction (para 57).
AGO 8244A
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