Lincoln Electric SHIELD-ARC 400AS-50, Руководство по эксплуатации

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IMA 554C Shield-Arc 400AS-50 Page 11
TROUBLE CAUSE WHAT TO DO
Machine starts, but has
the following faults:
continued: Short circuit in armature (7A). Locate fault using growler and repair or
(2 segments burnt in 4 locations 90° apart). replace
Field rheostat may be making poor contact and Inspect rheostat. Clean out and if necessary
overheating (9). increase finger tension on contact arm
by bending arm.
Field circuit may have variable resistance connections Check field current with ammeter to
or intermittent open circuit, due to loose connections or discover varying current. This applies to
broken wires (17), (8), (9) or (9A). both the main generator and alternator.
Current control brushholder support stud and mating If brushholder internal contact surface is
contact surfaces may be dirty or pitted and burned pitted and burned, replace the
(5A). brushholder and support stud. If the
contact tact surface is dirty, clean off the
brushholder stud and internal contact
surface. Apply mixture of three parts
silicone grease and one part zinc
powder (by weight) to stud.
Current control brushholder contact springs may be Inspect. Replace needed parts. Clean
worn out or missing. Contact surface may be dirty, internal contact surface of control device.
rough or pitted (5A). Do not Iubricate. Smooth up roughened
surface.
Current-adjusting mechanism may not be operating Check for loose or missing set screw in
properly (5A). control handles.
Engine speed low. Check nameplate for desired speed and
reset. (Refer engine instruction manual.)
Wrong grade of brushes may have been installed on Fit correct Lincoln brushes
generator (7).
Welding is loud and Series field (5) and armature circuit may be open Check circuit with voltmeter
spatters excessively circuited (7A).
Current setting may be too high. Check setting and current output with
ammeter
Polarity may be wrong. Check polarity. Try reversing polarity or
try an electrode of the opposite polarity
Maximum welding Open in series coil (5). Repair or replace
output all the time
Battery not charging Faulty battery charge alternator (22) Repair or replace
Faulty meter (14) Repair or replace meter
Battery may be fully charged.
Battery over-charging Faulty battery charge alternator (22). Repair or replace
Auxiliary power fails Capacitors faulty (13). Replace capacitors
under load
Welding current too Current control shaft and handle (5) may have turned With current control against the
great or too small slightly in the insulated bushing of the current control minimum stop, set the pointer to within
ompared to indication brushholder, caused by turning handle too hard against 3mm of last scale division.
on dial. one of the stops.
Alternator low causing low output compared Check for faulty rotor circuits
to dial indication.
Current control set to minimum and welder output so Check to see that the series field is
great that the engine stalls when arc is struck. properly connected & not shorted.
Engine running at incorrect speed. Set welder controls for maximum output
and weld. Then, while welding, check
engine R.P.M. The engine should be
running at full load speed. If indicator
shows a significant difference, consult
your engine instruction manual.
Welding output ok., but Aux power circuit breaker tripped. Reset
no auxiliary output. Broken wires. Repair or replace
Open circuit in auxiliary power (18) windings Repair or replace stator
TROUBLESHOOTING (Cont)