Theory Of Operation - Lincoln Electric POWER-ARC 4000 SVM103-A Service Manual

E-1
ENGINE
MECHANICAL
ROTATION
ENGINE, EXCITATION, ROTOR
AND STATOR
A small DC voltage developed by the flywheel alterna-
tor in the Briggs & Stratton engine is fed to the rotat-
ing field coil in the rotor via a brush and slip ring con-
figuration. This excitation ("flashing") voltage
magnetizes the rotor lamination. The rotor is mechan-
ically coupled to the engine. The rotating magnet
induces a voltage in the stationary windings of the
main alternator (stator).
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
POWER-ARC 4000

THEORY OF OPERATION

FIGURE E.2 – ENGINE, ROTOR AND STATOR
ROTOR
SLIP
RINGS
CAPACITOR
RHEOSTAT
REACTOR
STATOR
ROTOR
STATOR
115 AND 230VAC
RECEPTACLES
BRIDGE
Three separate and isolated windings are incorporated
in the stator lamination assembly. Each winding set
has a different number of turns, producing different
magnitudes of AC output voltages. The three windings
are the weld winding, the auxiliary power winding and
the field feedback winding. The field feedback wind-
ing provides rotor current during machine operation.
The output of the PowerArc 4000 is dependent on two
criteria: the engine RPM and the amount of current in
the rotor winding.
OUTPUT
TERMINALS