Electrical DATSUN 210 1979 User Guide

REMOVAL
AND

INSTALLATION

Disconnect

battery
ground
cable

Disconnect
harness

connector
and

battery
cable

at

magnetic
switch

2
Remove

bolts

securing
starting

motor
to
transmission

case
Pull

start

iog
motor

forward
and

remove
it

3
Inst
1I

starting
motor
in

reverse

order
of

removal

DISASSEMBLY

NON
REDUCTION
GEAR

TYPE

I
Disconnect

connecting
plate
from

M

terminal
of

magnetic
switch
Re

move
two

screws

securing
magnetic

switch
and
remove

magnetic
switch

assembly

2
Remove

dust
cover
E

ring
and

thrust
washer
s

EE311
@@

O

Fig
EE

8
Removing
DUll
Cover

E

ring
and
ThrUJJt

Washer

3
Remove
two
screws

securing

brush
holder

assembly

EE318

Fig
EE

9
Removing
Bru
h
Hold

Setacrews
Engine
Electrical

ystem

4
Remove
two
ihrough
bolts
and

rear
cover

5
Remove

brushes
from
their

hold

er

by
moving
each
brush

spring
away

from
brush
with
a
hook

Remove

brush
holder

6
Remove

yoke
assembly
and
with

draw

armature
assembly
and
shift

lever

7
Remove

pinion
stopper
located
at

the
end
of
armature
shaft
To
remove

stopper
first
move

stopper
toward

pinion
and
after

removing
stopper
clip

remove

stopper
with

overruniling

clutch
assembly
from
armature
shaft

EE271

Fig
EE

lg
Rf

moving
Pinion

Stopper

REDUCTION
GEAR
TYPE

1

Disconnect

connecting
plate
from

M
terminal
of

magnetic
switch
Re

move
two
screws

securing
magnetic

switch
and
remove

magnetic
switch

assembly

Note

Torsion

spring
can
be

pulled
off

magnetic
switch

2
Remove

through
baIts
and
rea

cover

Note

Rear
cover
can
be

pried
off
with

a
f1at
blade
screwdriver
inserted
be

tween
it

and

yoke
Be

careful
not

to
damage

packing
while

removing

reaf
cover

3
Remove

yoke
armature
and

brush
holder
as

an
assembly
from

center

housing

CAUTION

When

removing
be
careful
not
to

knock
brush
commutator
or
coil

against
any
adjacent
part

EE
6
o

7

EE615

Fig
EE
ll

Removing
Yo
and

Armature

4
To

remove
brush
holders

proceed

as
follows

I
Remove

brush
on

positive
side

from
its
holder

Note
Brush
on

positive
side
differs
in

that
it
is
isolated
from
brush
holder

and
its

lead
wire
is
connected
to

field
coil

2

Carefully
lifting
brush
on

nega

tive
side

away
from
commutator
sur

face
remove
it

from
brush
holder

EE616

Fig
EE
12

Removing
Br
h

5
Remove
bolts

securing
center

housing
to

gear
case
and
detach
center

housing

6
Remove

pinion

gear

CLEANING
AND

INSPECTION

Clean

all
disassembled

parts
but
do

not
use

grease
dissolving
solvents
for

cleaning
overrunning
clutch
armature

assembly
magnetic
switch

assembly

and
field
coils
since
such
a

solvent

would
dissolve

grease
packed
in
clutch

mechanism
and
would

damage
coils
or

other
insulators

Check
them
for
excessive

damage

or
wear
and

replace
if

necessary

TERMINAL

Check
terminal
for

damage
and

wear
and

replace
magnetic
switch

assembly
if

necessary

FIELD
COIL

Check
field
coil
for
insulation
If

the
insulation
of
oil
is

damaged
or

worn
it
should
be

replaced

Testing
field
coil
for

continuity

Connect
the

probe
of
a
circuit

tester
or
an
ohmmeter
to
field
coil

two

positive
terminal
of

positive
brush

holder

If
tester
shows
no

continuity
field

circuit

or
coil
is

open

Replace
it

Fig
EE

13

Testing
Field
Coil

for
Continuity

Testing
field

coli
for

ground

Place
one

probe
of
circuit
tester

onto
yoke
and
the
other

of
to
field

coil
lead

positive
terminal

If

very
little
resistance
is

read
field

coil
is

grounded

Replace
it

I

EE017

Fig
EE
14

Testing
Field
Coil

for
Ground
Engine
Electrical

System

BRUSHES
AND
BRUSH

LEAD
WIRE

Check
the
surface
condition
of

brush
contact
and
wear
of
brush
If
a

loose

contact
is
found
it
should
be

replaced

If
brush
is

worn
so
that
its
length
is

less
than

specified
value

replace

Minimum

length
of
brush

Non
reduction

gear
type

12
mm
0
47
in

Reduction

gear
type

11
mm
0
43
in

Check
the
connection

of
lead

clip

and
lead
wire

Check
brush
holders
and

spring
clip

to
see
if

they
are
not
deformed
or

bent
and
will

properly
hold
brushes

against
the
commutator

If

brushes
or
brush
holders
are

dirty
they
should
be
cleaned

BRUSH
SPRING
TENSION

Check
brush

spring
tension

by
a

spring
scale

as
shown
in

Fig
EE
l
5

If
it
is

faulty
replace
it

Spring
tension

Non
reduction

geaf
type

1
4
to
1
8

kg
3
1
to
4
0
Ib

Reduction

gear
type

1
6
to

2
0

kg
3
5
to
4
4
Ib

I

r

4
1

0
5

to
0
8
rom

O

iO

Correct

EE
7
ARMATURE
ASSEMBLY

Check
external

appearance
of

arma

ture
and

oommutator

I

Inspect
commutator
If
the

sur

face
of
commutator
is

rough
it
must

be
sanded

lightly
with
No
500

sand

paper
If

the

depth
of

insulating
mica

is

less
than
0
2
mm
0
008
in
from

commutator
surface

insulating
mica

should
also
be
undercut

so
that
its

depth
is
0
5

to
0

8
mm
0

020
to

0
031
in

The

wear
limit
of
commutator
dia

meter
is
I

mm
0
04
in
If
the

diameter
of
commutator

is
less
than

specified
value

replace
armature

assembly

Diameter
limit

Non
reduction

gear
type

32

mm
1
26
in

Reduction

gear
type

29
mm
1
14

in

I
@

EE018

Fig
EE

15
Inspecting
Bnah

Spring

Tension

c

I

File

Commutator

nt

I

1

11
Mica

Incorrect

EE021

Fig
EE
16

Undercutting
Imulating
Mica

2

Inspect
silldered
conneetibn
of

armature

lead
and

commutator
If

loose
connection
is
found

solder
it

using
resin
flux

3
Armature
test

for

ground

Using
a

circuit
tester

place
one
test

probe
onto
armature
core
or
shaft
and

other
onto
each

commutator
bar

If
tester

shows

continuity
armature

is

grounded
and
must
be

replaced

L
L

I

EE022

F
EE
17

Teating
Armature

for

Ground

4
Check

armature
for
short

by
plac

ing
it
on

armature
tester

growler

with
a

piece
of
iron

over
arma
t
ure

core

rotating
armature
If
the

plate

vibrates
armature
is

shorted

jeBel

EE023

Fig
EE

18

Testing
Armature
or

Short

5

Check
armature
for

continuity
by

placing
probes
of
tester
on
two

seg

ments
side

by
side
If
tester
shows
no

continuity
the
circuit

is

open

OVERRUNNING
CLUTCH

ASSEMBLY

Inspect
pinion
assembly
and
screw

sleeve
or

reduction

gear
Screw
sleeve

must
slide

freely
along
armature
shaft

splines
or

pinion

gear
shaft
must
slide

freely
through
reduction

gear
If

dam

age
is
found
or
resistance

except
nor

mal
resistance
due
to

spring
felt

when

sliding
it

must
be

repaired

Inspect

pinion
teeth
If
excessive

rubbing
is

found
on

teeth

replace
Flywheel
ring

gear
also
must
be

inspected
Engine
Electrical

System

@

ll

EE278

Fig
EE
19

Overrunning
Clutch

Assembly

1
Pinion

gear

2

Reduction

gear

EE617

Fig
EE
20
Pinion
and

Reduction

Gear

Overrunni11C
Clutch

AS5em

bly

BRUSH
HOLDER
TEST

FOR

GROUND

Using
a

circuit
tester

place
one
test

probe
onto

negative
side
of
brush

holder
and
another
onto

positive
side

If

tester
shows

continuity
brush
hold

er

is
shorted
to

ground
Replace
brush

holder

EE025

Fig
EE

21

Testing
Brush

for

Ground

BEARING
METAL

Non
reduction

gear
type

spect
bearing
metal
for

wear
or

side

play
If
the
clearance
between

bearing
metal
and
armature
shaft
is

more
than
0
2
mm

0
008
in

replace

metal

EE

8
BAI
L

BEARING

Reduction

gear
type

Holding
outer
race
with

finger

rotate

bearing
to
see
if
there
is

any

play
or
bind
If

necessary
replace

bearing

MAGNETic

SWITCH

ASSEMBLY

I

Using
a
circuit
tester

check
con

tinuity
between
S

terminal
of

mag

netic
switch
and

switch

body
metal

If

continuity
does
not
exist

shunt
coil
is

opened

Replace
switch

assembly

2
In
the

same
manner
as
above

check

continuity
between
terminals

S
and
M

If

continuity
does
not

exist
series
coil
is

opened

Replace
switch

assembly

ASSEMBLY

Reassemble

starting
motor
in
re

verse

sequence
of

disassembly

When

assembling
be
sure
to

apply

grease
to

gear
case

and
rear
cover

bearing
metal
and

apply
oil

lightly
to

pinion

TEST

PERFORMANCE
TEST

Starter
motor
should
be

subjected

to
a
no
load
test
whenever
it

has

been

overhauled

to
ensure
that

its

perfo
rmance
will
be

satisfactory
when

installed
on

engine
Starter
motor

should
also
be

subjected
to
the
test

when
the

cause
of
abnormal

operation

is

to
be
determined
A
brief
outline
of

the
test
is

given
below

No

loadtest

Connect

starting
motor
in
series

willi

specified
12
volts

battery
and

an
ammeter

capable
of

indicating

1

000

amperes

Specified
current
draw
and
rev6lu

tion
in
this
test
are
shown
in

Sp
ci

Cications

Starting
motor

S

DIAGNOSES
OF
TEST

I
Low

speed
with
no
load
and

high

current
draw

may
result
from
the

following

I
Tight
dirty
or
worn

bearings

2
Bent

armature
shaft
or

loosened

field

probe

3
Shorted
armature

Check
armature
further

4
A

grounded
armature
or
field

a
Remove

input
terminal

b
Raise
two

negative
side
brushes

from
commutator

c

Using
a
circuit

tester

place
one

probe
onto

input
terminal
and
the

other

onto

yoke

d
If

tester
indicates

continuity

raise

the
other
two
brushes
and
check

field

and
armature

separately
to
deter

mine

whether
field
or

armature
is

grounded

2
Failure
to

operate
with

high
cur

rent

draw
may
be

caused

by
the

following

I
A

grounded
or

open
field
coil

Inspect
the
connection
and

trace

circuit

with
a
circuit
tester

2
Armature
coil
does
not

operate

Inspect
commutator
for
excessive

burning
In
this

case
arc

may
occur
on

damaged
commutator
when
motor
is

operated
with
no
load

3

Burned
out

commutator
bar

Weak

brush

spring
tension
broken
Engine
Electrical

System

Switch

Battery

Vultmeter
Ammeter

EE738

Fig
EE

22
No
load

Testing

brush

spring
rubber
bush
thrust
out

of
mica

in

commuta
tor
or
a

loose

contact
between
brush
and

conunuta

tor
would
cause
commutator
bar

to

burn

3
Low
current

draw
and
low

no

load

speed
would

cause

high
internal

resistance
due
to
loose

connections

damaged
leads

dirty
commutator
and

causes
listed
on
item
2
3

MAGNETIC

SWITCH

ASSEMBLY
TEST

Switch

2

1
6

11

p
IB
b

I

Battery
Starter
motor

EE351

Fig
EE

23
Circuit

of
Magnetic

Switch

Assembly
Test

If
the

starting
motor

check
is

OK
check

magnetic
switch
assem

bly
Connect

cables
between

negative

battery
terminal

and
start

ing
motor
M

terminal

positive

battery
terminal

and

starting
motor

8
terminal

connecting
a

switch
in

series

as
shown
above

EE
9
Non
reduction

gear
type

With
the
switch

on

push
pinion

back
to
remove
all

slack
and
measure

the
clearance
between

pinion

front

edge
and

pinion
stopper

Clearance
L

0
3

to
2
5
mm

0
012
to
0

098
in

EE644

Fig
EE
24

Measuring
Clearance

l

Reduction

gear
type

Compare
difference
2
in

height

of

pinion
when
it
is

pushed
out

with

magnetic
switch
energized
and
when
it

is

pulled
out

by
hand
until
it
touches

stopper

Difference

L

0
3

to
1
5

mm

0
012
to
0
059
in

Pull

out

by

hand
until

pinion
stops
Push
out

1

1

n

11

r

L

Difference
EE688

Fig
EE
25

Measuri
g
Difference
L

If

necessary

adjust
it

by

changing

or

adding

adjusting
washer
s

Adjust

ing
washers
are
available

into

two

different
sizes
0
5

mm
0

020
in
and

0

8
mm
0
031

in

The

charging
circuit
consists
of
a

battery
an

alternator

incorporating
an

IC

voltage
regulator
and

wiring
that

connects
these

parts

The

purpose
of

this

system
is
to

convert
mec
hanka

energy
from
the

engine
into
electrical

energy
which
is

used
to

operate
all

electrically
operat

ed
units
and
to

keep
the

battery

fully

charged

With
the

ignition
switch
in
ON
the

circuit
between

transistor
uTr

I
of
the

lC

voltage
regulator
and

ground
is

closed
Current
from
the

battery
then

flows

along
the
route

shown

by
the

arrOW
in

Fig
EE
26

turning
on
the

charge

warning
lamp
and

flowing
on

through
terminal
L

to
excite
the

rotor

When
the
alternator

begins
to

oper

ate
three

phase
alternating
current
is
ngine
Elect
ical

System

CHARGING
CIRCUIT

indicated

in
the
stator

coil
This
alter

nating
current
is

rectified

by
the

posi

tive
and

negative
silicon

diodes

When
the

voltage
at
terminal
8
is

higher
than

battery
voltage
current

produced
at
the

stator
flows

to
re

charge
the

battery
While
the

battery
is

being
re

charged
the

voltage
at
termi

nal
L

is

equal
to
that
of
terminal

8
At
this

point
there
is
no

voltage

differential
on
either
side
of
the

charge

warning
lamp
which
causes
the

charge

warning
lamp
to
turn
off
In

other

words
current
does

not
flow
from
the

battery
to
terminal
L

Accordingly

current
flow

through
the
rotor
as

shown
in

Fig
EE
27

is
taken
over

by

current

produced
at
the
stator
The

circuit
between
terminal
F
and

Tr
is

then
closed
See

Fig
EE
27

The
IC

voltage
regulator
monitors
generating
voltage
to
be

applied
to
the

battery
at
terminal
S
When
current

exceeds
the

specified
value
it
then

flows

through
the
zener
diode
ZD

closing
the

circ
it

consisting
of

transis

tor
Tr
and
resistor

R1
At
this

point
current
neither
flows

through

transistor
Tr

I
to

ground
nor
to
the

rotor

thereby

reducing
the

voltage

generated
at
the

stator
See

Fig

EE
28

When

voltage
generated
at
terminal

S
is

reduced
to
the

specified
value

transistor

allows
current
to
flow

through
the

rotor

increasing
the

generating
voltage

In

this
manner

output
voltage
from

the
alternator
does

not
rise
above
the

specified
value

by
the
ON
OFF

opera

tion

of
the

rotor
coil

through
the
IC

voltage
regulator

16

L

R
l
I

01
0

ls

CHARGE
LAMP

J
011

L

e
0

u

a

M
e

i
J

0

io
o
IGNITION

a

0

09

SWITC1
R2

El1
STATOR
COIL

04
0
R

F

1
BATTERY

8

ZD

ALTERNATOR

7
I

1
AJ

TI
3

IC
VOLTAGE
REGULATOR
Aa

E

1

7

EE760

Fig
EE
26

Simplified
Charging
Circuit
Initial
excitation

current

EE
10

J

o

u

o

ll

ALTERNATOR

nJn
l

0
0
Engine
Electrical

System

F
00IB

RJ
1

1s

0111
CHARGE
LAMP

rt
ei

tOlD

11

1
IGNITION

SWITC1
R2
i
I
oJor

EB

R

BATTERY
f

3

07

09

0
4
0

1
8

r

I
G
XiJ

Tts
R
o

s
o

E

1

J

IC

VOLTAGE
REGULATOR

Fig
EE

27

Simplified
Charging
Circ14it
When

battery
voltage
is
lower
than

regulating

voltage
EE761

I

h
it

r

f

1
0
0
J

o

U

ll

o

I

o

cr

ALTERNATOR
m
l

01

03

1

X
RJ
16

I

1s

OIlI

r
CHARGE
LAMP

L

l

@
R2
IGNITION

SWITCH1
w

Lp

R
l
Q7

BATTERY

T

8

T
F
i
R

j

JZO

RS

E

J

7

Ie

VOLTAGE
REGULATOR

EE762

Fig
EE
28

Simplified
Cluzrging
Circuit

When

battery

voltage
i

higher
than

regulating

voltage

EE
11

FUSIBLE
LINK

FUSIBLE
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ALTERNATOR

lE
Ie

VOLTAGE

REGULATOR

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IGNITION

WR
SWITCH

BW

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AUTO

CHOKE

RELAY
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VR

1

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mID

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FUSE

BLOCK

CHARGE

WARNING

LAMP

5J

BL

Note

@

V

@
California
models

Non
Qilifomo
18
models

FU
models

Fig
EE
29
Circuit
Dinrswr
EE742

mofCIuJ

Tg
ng
Sy
t
m

EE
12

DESCRIPTION

The
alternator

incorporates
an
Ie

voltage
regulator
which
maintains
volt

age
within
the

specified
range
and

prevents

output
voltage
from

rising

higher
than
the

specified
value

Except

for
the
Ie
circuit

alternator

parts
are

essentially
the

same
as
those
of

the

conventional

type
alternator

Service

procedures
outlined
in

this

section
are
restricted
to
information

on

other
than
the

voltage
regulator

In
the

alternator
a

magnetic
field
is

CD
Engine
Electrical

System

ALTERNATOR

produced

by
the
rotor
which
consists

of

alternator
shaft
field
coil

pole

pieces
and

slip

rings
The

slip
rings

pressed
in
the

shaft
conduct

only
a

small

field
current

Output
current
is

generated
in
the
armature
coils
located

in
the
stator
The
stator
has
three

windings
and

generates
three

phase

alternating
current
Silicon
diodes
act

like
a

one

way
valve
for

electricity
so

that

charging
current

passes
easily
but

reverse
current
is
shut
out

In
this
alternator

pack
type
silicon
diodes
are
used

as
main
diodes

Nine

diodes
three

negative
three

positive
and
three

sub
diodes
are

installed
in

positive
and

negative
plates

as
an

assembly

These

diodes
are
direct

soldered
at

their

tips
and

constructed
with

posi

tive
and

negative
conjunction

They
are
mounted
on
the
two

plates
which
combine
the

function
of

heat

dissipating
plate
and

positive

negative
terminals
and
are

light
in

weight
and

easy
to

service

EE13
1

Pulley
assem
bly

2
Front
cover

3
Front

bearing

4
Rotor

Qj
5
Rear

bearing

6
Stator

7

Diode
Set

plate

assembly

8
Brush

assembly

9
Ie

voltage
regulator

10
Rear
cover

11

Through
bolt

EE647

Fig
EE
30
Alternator

REMOVAL

1

Disconnect

battery

negative

cable

2

Disconnect
two

lead
wires
and

oonnector
from
alternator

3

Loosen

adjusting
bolt

4

Remove
alternator
drive

belt

5

Remove

parts
associated
with

alternator
from

engine

6
Remove
alternator

from
car

DISASSEMBLY

I
Remove

through
bolts

Separate

front
cover
with
rotor

from
rear
cover

with
stator

by
lightly

tapping
front

bracket
with
a

wooden
mallet

rnJ

J

i

EE525

Separating
Front

COI
T

Fig
EE

31

2

Place
rear
cover
side
of

rotor
in
a

vise

with
soft

jaw
and

remove

pulley

nuts
Then
remove

pulley
and
fan

from
rotor
shaft

3

Remove

setscrews
from

bearing

retainer
and

separate
rotor
from
front

EE526

Fig
EE
32

Removing

Pulley
and
Fan

tr

s

0
27

Fig
EE
33
Removing
Rotor
Engine
Electrical

System

4
Pull

rear

bearfug
off
rotor

assem

bly
with
a

bearing
puller
or

press

EE037

Fig
EE
34

Pressing
Out

Rear

Bearing

I

EO

Fig
EE

35
Pulling
Out
Rear

Bearing

5

When

removing
IC

regulator

only

proceed
as
follows

I

Using

soldering
iron

disconnect

wire

connecting
diode

set

plate
to

brush
at
brush

terminal

2

Remove

bolt

securing
diode
set

plate
to
rear
cover
side
face

3

Remove
nut

securing
battery

terminal
bolt

4

To
facilitate
removal

s1ighly
lift

stator

coil

together
with
diode
set

plate
from

re
r
cover
Then
remove

screw

connecting
diode
set

plate
with

brush

5

Separate
stator
coil
and
diode

together
with

rear
cover
and

remove

brush
and

IC

regulator

6
Disconnect
stator

coil
lead
wires

from
diode
terminals
with

a

soldering

iron

Remove

screws

securing
brush
re

move
stator
from

rear
cover

EE648

Fig
EE
36

Removing
Stator

Coil

EE
14
7

Disconnect
wire
from
diode
tor

minal
at
brush
terminal
with

soldering

iron

Remove

brush

assembly
with
IC

regulator
by
loosening
screws

8
Remove
diode

holder

by
loosen

ing
screws

acefii
li

E
E649

Fig
EE

37

Removing
Diode
Holder

INSPECTION
AND

REPAIR

ROTOR
INSPECTION

I

Continuity
test
of
rotor
coil

Apply
tester
between

slip

rings
of

rotor
If

there
is

no

continuity
field

coil
is

open

Replace
rotor

assembly

Fig
EE

38

Continuity
Test

of

Rotor
Coil

2

Ground
test
of
rotor
coil

Check

continuity
between

slip
ring

and

rotor
core
If

continuity
exists

replace
rotor

assembly
because
rotor

coil

or

slip
ring
may
be

grounded

EE532

Fig
EE
39
Te

ting
Rotor
Coil

for
Ground

INSPECTION
OF
STATOR

Continuity
test

Stator
is
normal
when
there
is

continuity
between
individual
stator

coil

terminals
When
there
is

no
conti

nuity
between
individual
terminals

cable
is

broken

Replace
stator

assembly

EE533

Fig
EE
40

Testing
Stator

for

Continuity

2

Ground
test

If
each
lead

wire
of
stator
coil

including
neutral
wire
is

not
conduc

tive
with
stator
core
condition
is

satisfactory
If
there
is

continuity

stator

coil
is

grounded

EE534

Fig
EE
41

Testing
Stator

for

Ground

INSPECTION
OF
DIODE

Perform
a

continuity
test
on
diodes

in

both
directions

using
an
ohmmeter

There
are
six
main

diodes
and
tluee

sub
diodes
attached
to
set

plate
Three

main
diodes
are
attached

to

positive

EEl
plate
and
three
others

to

negative

8
plate
Three
sub
diodes
are

attached

to
terminals

The

continuity
test
should
be

per

formed
on
each
diode
between

the

terminal
and

plate
Engine
Electrical

System

Conductive
direction

EE045

Main
diode

installed
on

8
plate

is
a

positive
diode
which
allows

cur

rent
to

flow
from
terminal
to

EEl
plate

only
In

other
words
current
does
not

flow
from

8
plate
to

terminal

1

plate

2

Terminal

Fig
EE
43

Impecting
Positive

Diode
EE046

2

Main
diode
installed
on

Gplate
is

a

negative
diode

which
allows
current

to
flow
from

Gplate
to
terminal

only

In

other
words
current
does
not
flow

from

terminal

toGplate

1

plate

2

Tenninal

Fig
EE
44

Impecting
Negatiue

Diode
EE047

EE
15
rp

m

1

plate

2

ptate

3
Diode

Fig
EE

42
Conductive
Direction

of
Diode

3
Correct
direction
of

current
flow

for
three
sub

diodes
is
shown
in

Fig

EE
4S

Direction
of

electric
current

EE650

Fig
EE
45

Sub
Diode

If

current
flows
in
both

positive

and

negative
directions
diode
is
short

circuited
If
current
flows
in
one

direc

tion

only
diode
is
in

good
condition

If
there
is
a

faulty
main

diode

replace

all
diodes
as
an
assembly
See

table

below
These
diodes
are
unservicea

ble