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13-20
GROUP
13-CHARGING SYSTEM
mounted inside the slip ring end
head on the ACR type alternator,
while on the AC type alternator the
remote voltage regulator is mounted
on the fender
apron.
In effect its action is similar to
that of the vibrating contact type
of voltage regulator, but
switchin~
of
the field circuit is achieved by tran-
sistors instead of vibrating
contacts.
No cut-out is required since the diodes
incorporated in the alternator prevent
reverse currents from
flowing.
No
current regulator is required as the
inherent self regulating properties of
the alternator limit the output current
to a safe
value.
Design features include tempera-
ture compensation without the use of
a thermistor, radio frequency inter-
ference
suppression,
requires no ad-
justment in service.
The voltage regulator and alter-
nator are isolated from the battery
when the engine is stationary by
means of the ignition switch.
OPERATION
With the ignition switch turned
on and the engine running (Fig.
24),
the flow of current through the ro-
tor
field
coil energises
the twelve
pole rotating electro
magnet.
The
rotation of the energised rotor unit
induces an A.C. voltage in the three
phase rotor winding which is con-
verted into
D.C.
by the aix diode
rectifiers and conducted to
the
+
output
terminal
The rectifiers, which only
conduct
in one direction, prevent the- battery
which is 'directly and permanently
connected to the alternator output
terminal, from discharging through
the alternator.
This characteristic
of the rectifiers eliminates the need
for a cut-out relay, BUT IT IS
ESSENTIAL THAT
THE
BAT-
TERY MUST ALWAYS BE CON-
NECTED WITH THE
NEGATIVE
TERMINAL TO
GROUND. FAIL-
URE TO CONNECT A
BATTERY
WITH THE CORRECT POLARITY
EJ
REMOVAL AND INSTALLATION
REMOVAL
&
INSTALLATION
REMOVAL
1.
Disconnect the battery ground
cable.
2. Loosen the alternator mount-
ing bolts and remove the adjust-
ment arm to alternator
bolt.
(Bet-
ter access to these may be possible
with the vehicle raised)
.
3. Disengage the alternator belt.
Remove
the
alternator
mounting
bolt, disconnect the
alterna
tor wir-
ing
harness
a
nd
remove
the
alter-
nator.
INSTALLATION
1.
Attach
the
alternator
wiring
harness. Position the alternator to
the
~ngine,
and install the alternator
mounting
bolt finger-tight.
EJ
MAJOR REPAIR OPERATION
DISMANTLING THE ALTERNATOR
1.
Mark both end housings and
the stator with a scribe mark.
2. Withdraw the three through
bolts.
3. Separate the drive end head
and rotor sub-assembly from the slip
ring end head and stator sub-assembly.
Do not loose the wave washer from
the slip ring end head bearing
recess.
4.
Using a pair of long nose pliers
as a heat sink on the stator wire
quickly unsolder the stator leads
from the terminal strips on the recti-
fier pack and remove the stator
from the slip ring end head.
5.
Remove the two rectifier pack
attaching nuts, spring and flat washers.
Remove the brush gear attaching
screw.
Remove the voltage regulator
attaching screws (ACR models
only).
The rectifier pack, brush gear and
voltage regulator (ACR models only)
may now be removed as an
assembly.
NOTE: The rectifier pack may now
be tested as detailed on Page 11 of
Part 1 and if further dismantling is
necessary proceed .as follows.
6.
ACR models
only, unsolder
the regulator leads at the brush
gear.
7. Unsolder field diode connec-
tions on brush
gear
terminal.
NOTE:
It
is important this unsolder-
ing operation be carried out as quickly
as possible as excessive
heat
trans-
ference from the soldering iron to the
brush box moulding could warp the
moulding and.result in restricting
the
free movement of the brushes. This
also applies when soldering on the
field diode connections during re-
assembly of the alternator.
8.
Using a pair of long nose pliers
as a heat sink grip each of the semi-
conductor wiring terminations in turn
WI LL DAMAGE THE ALTERNA-
TOR
AND REGULATOR.
DIS-
CONN ECT ONE VEHICLE BAT-
TERY LEAD WHEN USING A
QUICK CHARGER.
Portion of the output current is fed
through the field diodes to the voltage
regulator. From the regulator this current
goes to ground via the field windings.
As the speed of the rotor in-
creases, the induced voltage in the
stator
winding increases, causing
more current to flow to satisfy the
load equirements. However, the in-
ductive
reactance
of
the
stator
winding provides an automatic up-
per limit on the current output of
the alternator.
The function of the voltage limi-
ter is to control the output voltage
of the Alternator to meet the needa
of
the
vehicle
electrical system
which it accomplishes by controll-
ing the flow of current in the rotor
field coil.
2.
Install the adjustment arm to
a lternator bolt.
3. Adjust the belt tension using
tool T63L-8620-A
.
Apply pressure
on
the
alternator
front
housing
<'nly,
when
tightening
the
belt.
Tighten the adjusting arm bolts
and the mounting
bolt.
4.
Lower the car and connect the
battery ground cable.
and unsolder the three wires from
each, this will separate the Positive,
Negative
and field diode heat sinks.
NOTES:
(a) Field diode assembly consisting
of three field diodes and insulated
moulding
is serviced as one unit.
(b
)Positive and Negative heat sinks
are serviced separately as complete
units, each unit comprising three
diodes and heat sink.
( c) The rectifier insulators and heat
sink separators are serviced as a com-
plete kit.
For electrical tests on the com-
ponents refer to pages 10 and 11 of
part one of this group.
ASSEMBLY
1. Reassemble the rectifier assem-
bly placing the four insulation pieces
and
the Positive male Lucar in original
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