7.1.1 Battery-Charging Generator Regulator
DETROIT DIESEL 53
Operation
CONTROL RELAY
When the ignition switch is "OFF", the contact points are
held apart by the tension of a spiral spring acting on the
In addition to a circuit breaker and a voltage regulator.
armature. When the ignition switch is turned "ON",
the three-unit regulator has a control relay unit. This
battery current flows through the control relay winding to
unit has a core with a single shunt winding connected
ground. The magnetic field produced by the winding
from the "SW" terminal of the regulator to ground. The
overcomes the armature spring tension and pulls the
winding and core are assembled into a frame. A flat
armature down causing the contact points to close. This
steel armature supporting the upper one of two relay
completes the circuit to ground for the circuit breaker
contacts is attached to the frame by a hinge and is
relay winding so that it can operate when the D.C.
centered above the core. The lower contact point is
voltage from the power rectifier reaches the value for
supported by a detachable contact support insulated
which the circuit breaker relay is adjusted. The control
from the frame. An armature stop is assembled above
relay contact points remain closed until the ignition
the upper contact.
switch is turned "OFF".
TRANSISTORIZED AND TRANSISTOR REGULATORS
a vibrating voltage regulator unit and a field relay unit.
In addition to the standard regulator. there are two other
The other is a transistor regulator which contains no
types of regulators being used with the self-rectifying
moving parts and is used with a separately mounted
A.C. generators in the battery-charging circuit. One Is a
field relay.
transistorized regulator which contains
TRANSISTORIZED REGULATOR
damage from transient voltages which may appear in
The transistorized regulator (Fig. 3). for use on a
the system.
negative ground circuit. contains a vibrating voltage
regulator unit and a field relay unit. The regulator uses
Certain transistorized regulators are equipped with a
a single transistor and two diodes. The transistor works
choke coil to permit the installation of a capacitor
In conjunction with the conventional voltage unit having
between the regulator and the "BAT" terminal on
a vibrating contact point to limit the generator voltage to
installations experiencing radio interference.
The
a preset value. A field discharge diode reduces arcing
capacitor suppresses the radio noise and the choke coil
at the voltage regulator contacts by dissipating the
energy created in the generator field windings when the
contacts separate.
A suppression diode prevents
Fig. 3. - Transistorized Regulator
1971 General Motors Corp.
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