The Washington herald. [volume] (Washington, D.C.) 1906-1939, 1921-06-19
DIAGRAM OF WIRES
CLEARSAWAYMANY
KNOTTY PROBLEMS
First Difficulties Detected
By Close Watch on
Meter.
NEEDS QUICK ACTION
Frequent Inspection of All
Wires Helps Keep Car
In Order.
NEEDS QUICK ACTION

lighting system is something tnat
fills the soul of the average car
owner with dread. Yet a careful
look at the wiring diagram Of his
car will serve to unravel most
difficulties. especially IL he under
stands a few basic principles.
which we purpose explaining in
this story.
The electric starting and light
ing system of the car usually con-
sists of a generator and starting
motor, either separate or included
in a single unit: a storage battery
which is charged BY the genera
tor and then feeds its current to
the starting motor and to the
lamps. Then there is cutout
which connects and disconnects
the generator to or from the bat
terry at slow engine speeds. and
there is also a device to regulate
the charging rate to conform to
the service usually demanded of
the car. These with various
wires. switches. lamps. etc. COM
plete the system.
To begin with, there is mounted
on the dash Of the modern car a
meter of some type to register the
charge and discharge of the bat
terry, so that the driver can tell
how the starting and lighting
he
starting pedal is depressed the
meter begins to register discharge
because the battery is being
drawn upon for current to turn
the. starting motor over. Some
times the meter gets out Of order.
When the motor is not running
and when the lights are not burn
ing the hand of the meter should
register zero. If it does not so
register the hand is bent or the
magnet of the instrument may be
weak or the return spring may
not be strong enough. II the
error is more than a trihing one
the meter should be inspected in
ternally. vibration and excessive
voltage sometimes cause derange-
ment in these meters, and in this
case the car owner had better
take the instrument to the service
station.
Wear In Bearings.
1t is not often that mechanical
troubles afhict the starting and
lighting system. Wear in the
bearings of the generator and
starting motor is the commonest
mechanical ill. Sometimes there
is trouble in the linkage or in the
gearing and in the mechanical
governor. With these troubles
the car owner can cope just as
easily as those in other parts Of
the mechanism.
Electrical troubles obviously are
among the commonest that occur
in this system and they are most
ly caused by open circuits or
shorts. In the former case there
will be no flow of current at all,
while in the latter the flow will
be in the wrong direction. where
by the actual work of the system
is sighted. as when one uncovered
wire touches another on a different
circuit
Need of Inspection
II is necessary to inspect the
entire wiring system at frequent
intervals, because open circuits
and shorts are likely to occur at
any time. The chatting through OF
the insulation of a wire is enough
to prevent the current from flow
ing to the place where it is need
ed Constant vigilance is the price
Of starting and lighting ethciency'
There are two methods of run
ming the wires from the battery to
the lamps, etc, known respective
ly as single and double wiring.
In the double wiring system two
wires are used, one to carry the
current to its place, where it is
needed, and another to bring it
back to the battery. In the sin
gle wire system one wire carries
the current out. while the return
is accomplished through the metal
of the cars frame. II the wire
of a single wire system is stripped
of its insulation and touches the
metal of the car a short circuit
is established and the part served
by that wire will not operate at
all: if il is lamp it will not
burn. In the two wire system a
short does not form so easily. as
two wires must be out of business
to cause it.
Trouble In Terminals
The terminals are source Of
great trouble in this system. One
poor terminal connection may put
the whole system out of order. or
1t may simply prevent one of the
units working properly. In case
of trouble inspect these parts.
II the starting motor does not