General Description - Cadillac 1937 LaSalle VVI Information

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E L E C T R I C A L
General Description
T h e electrical systems of a l l 37-series cars are of
the same general arrangement a n d design, differ-
ing mainly i n the types of generator charging
circuits used. T h e batteries of the various series
are of the same type but differ in size a n d capacity.
G E N E R A T O R C I R C U I T
T w o types of generator circuits are used. O n e
type, employing a generator with a fixed 3rd
brush a n d a voltage regulator, is used o n series
37-50, 60 and 65 cars. T h e other circuit, of the
current controlled, voltage-regulated type, is
used on series 37-70, 75, 85 a n d 90 cars. Figures
6 a n d 7 of P l a t e 62 are diagrams of the t w o
circuits.
Generator—Series 37-50, 60 a n d 65
A D e l c o - R e m y generator M o d e l 918-C is used
on series 37-50, 60 a n d 65. T h i s generator has a
high charging rate which is controlled b y a
vibrating voltage regulator. T h e charging rate
of the generator is limited b y a non-adjustable
t h i r d brush a n d the voltage is controlled b y the
voltage regulator. Openings i n the rear of the
generator allow air to be drawn through the
generator to the front where it is expelled b y a
rotary fan which is a part of the generator pulley.
Voltage Regulator U n i t
T h e voltage regulator unit consists of a cutout
relay a n d v i b r a t i n g voltage regulator which are
mounted o n a metal base a n d covered b y a metal
cover to keep o u t dust, dirt, moisture, etc. T h i s
regulator assembly is mounted on the left hand
side of the engine side of the dash.
T h e purpose of the cutout relay is to break the
circuit between the battery a n d the generator when
the generator voltage is less than the battery
voltage i n order to prevent the battery from dis-
charging through the generator. In addition to
this, the relay controls the ammeter i n the instru-
ment cluster which indicates whether the generator
is charging or the battery discharging.
T h e v i b r a t i n g voltage regulator controls the
output of the generator. It decreases the charging
rate of the generator automatically when the
battery approaches a charged condition, b y
allowing a resistance to be cut into the field circuit
of the generator. W h e n the lights or other elec-
trical loads are turned on, the charging rate will
increase to take care of them, u p to the m a x i m u m
output o f the generator. T h e generator output,
therefore, is dependent upon the voltage setting of
the regulator, the connected load, and the condi-
tion of charge of the battery. A low output w i t h
a fully charged battery indicates that the regulator
is working properly.
Generator—Series 37-70, 75, 85 & 90
A D e l c o - R e m y generator, M o d e l 961-K, is used
on series 37-70 and 75. Series 37-85 a n d 90 uses
a M o d e l 9 3 3 - M generator, which is similar in
design but ventilated i n a different manner.
T h e generators used o n series 70 and 75 are
ventilated b y a stream of air being drawn through
from the back of the generator by a rotary fan
which is part of the generator pulley. T h e gener-
ator used on series 85 a n d 90 is ventilated by means
of an air horn which is located on the top of and
toward the front of the generator field frame, and
an outlet tube which is located at the rear bottom
of the field frame.
T h e generator on series 70 and 75 is belt driven
and is located i n the V of the engine.. T h e gener-
ator on series 85 a n d 90 is chain driven and is
located on the lower right hand side of the engine.
Aside from these differences, the generators used
on series 37-70, 75, 85 and 90 are essentially the
same. T h e y are k n o w n as "Peak L o a d " gener-
ators, having both current a n d voltage regulation.
Regulator U n i t
T h e D e l c o - R e m y regulators in the charging
circuit are made_ up of three separate units—a
cut-out relay, a current regulator, and a voltage
regulator. A l l of these units are mounted on a
single base and are enclosed b y a dust and moisture
proof metal cover. T h i s assembly is m6unted on
the left hand engine side of the dash (right hand
side on series 37-90).
T h e cut-out relay is similar to the conventional
cut-out relay except that the series windings are
heavier i n order to adequately carry the high
current output of the generator.
T h e central unit^of the regulator assembly is
the current regulator, which is composed of a
heavy winding in series w i t h the-generator charg-
ing circuit. T h e contact points are n o r m a l l y
held in a closed position due-to the tension of the
armature spring. W h e n the generator output
reaches a predetermined value, the magnetic pull
on the armature overcomes the spring tension and
the contact points open, inserting a high resistance
into the field circuit of the generator.
T h e voltage regulator u n i t is similar to the
current regulator except that one of the cores is
wound w i t h a large number of turns of small wire
connected between the ground and the "off" side
of the ignition switch. T h e current in this wind-
ing varies w i t h the battery voltage. Whenever
the battery voltage reaches a predetermined value,
the magnetic pull on the armature overcomes the
spring tension and the contact points open,