Dodge 50 Starter / Alternator / Dynamo

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Alternator
MODELS
ACS, 11 AC, 15ACR, 17ACR, 18ACR,
23ACR, AH 5/45, A133/55, LR135-111,
LR135-113, LR135-114, LR150-160, A1 27
and OAR.

General
These are driven by the engine in the same manner as
a D.C. Generator, namely, belt driven from the crank-
shaft pulley, but the advantage lies in their ability to
provide higher maximum output at lower speeds, to
cope with increased electrical load demanded by
modern equipment and decreased road speeds owing
to increased density of traffic, especially in built up
areas. They are also much lighter in weight, output for
output.

As opposed to the DC Generator in which the armature
windings rotate inside a stationary field system, the
alternator has a rotating field system inside a stationary
generating winding. When the rotor rotates inside the
stator, the output produced is alternating current (AC).
This is unsuitable for charging the battery which re-
quires direct current (DC), so it is rectified by means
of diodes which convert it to uni-directional flow to the
battery.

The alternator voltage output is maintained within close
limits by means of a control box which is fully tran-
sistorised and functions as a fast switch.

The alternator charging system will normally require
very little attention, but it should be kept free from
build-up of dirt, and a check made if it fails to keep the
battery charged.

a) Regularly inspect the driving belts for wear and
correct tension. It is important to ensure that all
belts on a multiple belt drive have equal tension
and are each carrying their share of the load. Slack
belts will wear rapidly and cause slip which will
not drive the alternator at the required speed.
Drive belts which are too tight impose severe side
thrust on the alternator bearings and shorten their
life. Periodically ensure that the alternator is
correctly aligned to the drive.

b) Do not replace faulty belts individually in a multi-
belt system. A complete matched set of drive belts
must always be used.

c) Keep the alternator clean with a cloth moistened in
kerosene or cleaning fluids. Ensure that ventilation
slots and air spaces are clear and unobstructed.

d) Remove any dirt accumulated on the regulator/
control box housing, and ensure that cooling air
can pass freely over the casing.

e) DO NOT "flash" connections to check for current
flow. No matter how brief the contact the tran-
sistors may be ruined.

Precautions
As previously described the diodes in the alternator
function as one-way valves and the transistors in the
regulator/control box operate as fast switches. Both are
accurate and sensitive.

They do not wear out and cannot be adjusted, but because
they are sensitive to voltage changes and high temperature,
the precautions are vital to prevent them from being destroyed.

a) DO NOT disconnect the battery whilst the engine is
running. This will cause a voltage surge in the
alternator charging system that will immediately
ruin the diodes or transistors.

b) DO NOT disconnect a lead without first stopping
the engine and turrung all electrical switches to
the off position.

c) DO NOT cause a short circuit by connecting leads
to incorrect terminals. Always identify a lead to its
correct terminal. A short circuit or wrong con-
nection giving reverse polarity will immediately
and permanently ruin transistors or diodes.

d) DO NOT connect a battery into the system without
checking for correct polarity and voltage.
Fault Finding on ACS

The AC 5 alternator is so designed that a flow of
current indicated either by the extinguishing of the
warning light, or as shown on the ammeter, is sufficient
evidence that the system is in proper working order.
Therefore, no open circuit, voltage or current output
checks should be performed on the installation
UN LESS-

a) The warning light fails to illuminate when the
generator is stationary, and the switch is closed OR
fails to become extinguished when the alternator is
running.
b) No charging current is shown on ammeter.
c) The battery is flat.
d) The battery is "boiling", indicating loss of voltage
control.
If any of the above symptoms occur, the procedure in-
dicated below and next should be followed.

a) Connect a good quality moving coil voltmeter 0-50
volts range across the battery or regulator negative terminal,

and one of the three positive terminals
marked LO, MED, HI. Disconnect alternator output
terminal. Fit a good quality moving coil 0 - 100 amp
ammeter in series with the alternator terminal and
output lead. The battery should be in a charged
condition. Continue