TM 5-3810-300-24&P-3
7.1.1 REGULATOR FOR BATTERY-CHARGING GENERATOR
turns of fine wire which, in series with a resistor, is
current winding. The series winding, consisting of a few
shunted across the generator at all times. The second
turns of heavy wire, is connected into the charging circuit
winding is a field current winding which is connected
so the full output of the generator passes through it. The
between the generator field circuit and ground whenever
field current winding is connected in series with the
the regulator contact points are closed. In addition to the
generator field circuit so the field current flows through it
core frame, armature and contact points, the unit has a
when the regulator contact points are closed.
spiral spring which holds the armature away from the
core so the two contact points are touching when the
The outward appearance of the current regulator is
voltage regulator is not operating.
similar to that of the voltage regulator.
Operation
Operation
When the generator voltage reaches the value for which
The magnetism produced by current flowing through the
the voltage regulator is adjusted, the combined magnetic
series winding overcomes the armature spring tension,
field produced by the shunt winding and the field current
and the contact points open when the current reaches
winding overcomes the armature spring tension, pulls the
the value for which the current regulator is adjusted.
armature down, and separates the voltage regulator
This inserts a resistance into the generator field circuit,
contact points. This introduces resistance into the
resulting in a drop in generator output. Immediately, the
generator field circuit so the generator field current and
magnetic field of the series winding is weakened, the
generator voltage are reduced. The lowering of the
contact points close, the generator output starts to
output of the generator causes the points to again close,
increase and the cycle is repeated. This action prevents
thereby removing the resistance and increasing the
the generator from exceeding its rated output.
generator output. The complete cycle, of opening and
closing of the points and the alternate inserting and
Therefore, when the load demand is heavy, generator
removing of the resistance in the generator field circuit, is
output will increase until it reaches the current value for
done rapidly, thus limiting the generator voltage to a
which the current regulator is set; then, the current
predetermined maximum value. With the generator
regulator will begin to operate and pre-regulate the
voltage limited, the generator supplies varying amounts
current output from the generator.
of current to meet the requirements of varying states of
battery charge and electrical loads.
After any check or adjustment of the voltage regulator, it
is necessary to polarize the generator before starting the
engine to assure correct polarity with respect to the
battery.
CURRENT REGULATOR
The current regulator contains two windings assembled
on one core, a series winding and a field
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