1973 DATSUN B110 Charging system

ENGINE
ElECTRICAL

SYSTEM

CHARGING
CIRCUIT

IGNITION

1

i
n

ITCH

r
B

i
i

vel

oU

ARMATURE

lip
J

l
t

lJ

FIEL

Df

e
I
I
3
2

I

u
P

5
0

IL
U
p

P
f

H
i

I

I

L

J

L
J

ALTERNATOR

VOL
TAGE

REGULATOR
The

charging
circuit

consists
of
the

battery
alternator

regulator
and

necessary
wiring
to
connect

these

parts
The

purpose
of
this

system
is
to
convert

mechanical

energy

from
the

engine
into

electrical

energy
which

is
used
to

operate
all

electrically
operated
units
and
to

keep
the

battery
fully
charged

When
the

ignition
switch
is

set
to
on

current
flows

from
the

battery
to

ground
through
the

ignition
switch

voltage

regulator
IG
terminal

primary
side
contact

point

PI

movable

contact

point
P2

voltage
regulator
F

terminal
alternator
F
terminal

field
coil
and
alternator

E

terminal
as
shown
in

Figure
EE
27

by
full

line
arrow

marks
Then

the
rotor
in
the
alternator
is
exited
On
the

other

hand
current
flows
from
the

battery
to

ground

through
the

ignition
switch

warning
lamp
voltage
regu

lator
L
terminal

lamp
side

contact

point
P4

movable
contact

point
PS
and

voltage

regulator
E

terminal
as
shown

by
dotted
line

arrow
marks
Then
the

warning
lamp
ligh
ts

When
the

alternator

begins
to

operate
three

phase

alternating
current
is

induced
in
the

armature
This

alternating
current
is

rectified

by
the

positive
and

negative

silicon

diodes
The

rectified
direct
current

output
reaches

the
alternator
A
and

E
terminals

On

the
other
hand
the
neutral

point
voltage
reaches

N
and
E

terminals

nearly
a

half
of
the

output

voltage
and

current
flows

from

voltage
regulator
N

terminal
to
E

terminal
or

ground
through
the
coil
VCI
as
shown
in

Figure
EE

28

by
the
dolled

line

arrow

marks
Then
the

coil
vc
I
is

excited
and
the

movable

contact

point
P5

comes
into
contact

with

voltage

winding
side
contact

point
P6
This
action

causes
to

turn
off
the

warning
lamp
and

complete
the

voltage

winding
circuit
as

shown

by
the
ullline
arrow
marks

When
the

alternator

speed
is
increased
or

the

voltage

starts
to
rise

excessively
the
movable
contact

point
P2

is

separated
from

the

primary
side
contact
P

1

by
the

magnetic
force
of

coil
V2

Therefore

register
RI
is

applied
into
the
field
circuit

and

output
voltage
is

decreased
As
the

outpu
t

voltage
is

decreased
the

movable

contact

point
P2

and

primary
side

contact
PI
comes

into

contact
once

again
and

the
alternator

voltage

increases

Thus
the

rapid
vibration

of
the

movable

contact

point
P2
maintains
an

alternator

output

voltage
to
constant

When
the

alternator

speed
is

further
increased
or
the

voltage
starts
to
rise

excessively
the

movable
contact

point

P2

comes
into
contact
with

secondary
side

contact

point
finally
Then
the

field
current
is
shut
off
and

alternator

output
voltage
is
decreased

immediately
This

action

causes
to

separate
movable
contact
P2
from

secondary
contact
P3

Thus
the

rapid
vibration
of
the

movable
contact

point
P2
or

breaking
and

completing

the
field
circuit
maintains
an
alternator

output
voltage
to

constant

j

T
SA

TIERY

I

l

e

7

Fig
EE
27

ChaTging
ciTcuit
1

EE
15