The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1893-10-17
WHY THE CARS MOVE
Some of the Mysteries of Electrical
LocOmotiOn Explained.
Tracing the Force from the Power
House to Its Application Under
the Hand of the MOtOrman.
Brooklyn Eagle.

to answer the question of motive power.
With a desire to know just how the car
was propelled the writer called on Mr.. ".
A. II. Bogardus secretary of the Brooklyn
City Railroad Company, with the question:
what makes the trolley car go and how
does it do it?''
81 suppose the best way TO answer that
question" said Mr.. Bogardus, lis TO begin
at the beginning We will take one Of the
company's three power stations, that To-
Gated at Fifty-second street, Bay Ridge.
This station when completed will have a
force of 1900 horse power. There are
twelve batteries Of boilers-two boilers
each. They are water tube boilers of 1000
horse power to each battery. Two of these
batteries will be in reserve to take the
place of any other battery in case of need.
The plant being on the water front re-
ceives it coal in barges at the DOCK from
which it is carried by elevators to pockets,
from which it is conveyed by chutes to the
front of each boiler. Each boiler carries
a pressure of 160 pounds of steam. which
drives the engines. There are eight cross
compound condensing Corliss engines of a
nominal capacity of 1000 horse power each,
but which can develop 1,500 horse power if
desired. Sea water is used for condensing
purposes. An economser is used with
which the feed water for the boiler is
heated to a high temperature by the ex-
haust heat on the way to the chimneys.
The engines are belted direct to a general
ing pulley wheel, on each end of the shaft
OF which is a clutch which makes 1t posi-
bic to run one. or two dynamos or electric
generators, from each engine. The gen
Grated current goes to a switch board
which regulates the amount of current
each generator is called to produce, and
SHOWS the amount put out and the in
tenslty or pressure of voltage. A generator
is a very liberal WORKER and would tear
ltseif TO pieces by keeping turning out
power until stopped, and 1t Is, therefore
necessary to have safety appliances viz
circuit branches and foiSes, in connection
with IT, which act as check valves On the
sWitcn board also are instruments showing
the amount of current on the feeders The
feeders are the large wires that are seen
on on the trolley poles or on the elevated
ROADS, ana are used to convey the current
from the power station to various points to
properly distribute the power The feeder
capIes are composed of a number of small
wires covered with weather-proof insuIa-
tion, ano are one and half inches out
slde diameter. 1t is better to make these
cables o. small wires twisted, on account
of fexibii,ty. 1t would he innossihIe 70
handle cable if it was one solid wire.
THE TROLLEY WIRE.
A naked trolley wire is hung over a line
or point between the rails of each track
This is hung on clips Ghe insulated ioinD
that connect it to the span wires which are
stretched from pole to pole The trolley
wire is insulated from the span wire. the
span wire is insulated from the poles and
the poles resting in cement beds are in
sulated in great degree from the ground
me feed wire comes from the switch
board and runs till it arrives at a section
or the road to which it is to furnish the
take the current off the feed wire as soon
as 1T left the power house we would be I'M
aele to obtain voltage at the extreme end
or the line. There is, therefore, one feed
wire to each district. When the feed wire
arrives at point it is intended to feed
smaller wires are splced on the feed wire
and are pulled out along the span wire and
connected with the trolley wire. These con
nccting wires are called mains. This con
untli enough mains are tapped to the
trolley wire 10 take from the feed wire all
the current the copper in the feeder viii
overload the feeders, and ii is therefore
necessary that the trolley wires be cut
into sections and insulated one section
from another TO prevent the electric cur
rent from running from one road to an
other. This acts as check or safeguard
aud should one section meet with an ac-
cldcnt it Is cut out, and the entire road
can be operated up TO that part. The pos
tive pole of the generator is connected
with the feeders through which the current
passes to the main wires, and then to the
trolley wire To the negative pole of the
generator is connected an overhead ground
wire to bring the current back TO the power
station. The overhead ground wire con-
meets with a timed copper wire laid under
ground between the rails. The rails when
laid are connected by bond wires-pieces
of timed copper wires-which are riveted
one end in each rail. These bonds are con-
nected to the supplementary wire in cen
the rail through the bond, the supple
mentary wires and the overhead ground
wire the circuit is complete to the negative
pole Of the DYNAMO ut the power house.
Now, while these connections are COM
plete, there IS no current unless the posi-
tive and negative poles are connected. This
connection is made through the motor car.
The motor that operates the car is sus-
pended on the axle of the wheels of the car,
| radius from the axle Is, at all times the
| same for the purpose of making the pinion
| (or small cog wheeD on the armiture shaft
exactly meet with the geer on the axle of
the wheel. The motor is the reverse of the
dynamo or generator. Whereas the dynamo
| generates electricity by the revolving of the
armiture, the motor reverses the current
and it is converted by the armiture of mo-
tor back into power. The electric motor is
| a revolving electro magnet, or rather a
| wheel or drum made of innumerable electro
magnets and the electric current passes
through the armiture in order to make it
revolVe certain segments are magnetized.
| If every segment magnetized at the
same time there would be no revolutions.
CONTROLLING THE CURRENT.
THE trolley wheel at the end of the pole
| on the top of the car is held in contact
| with the trolley wire by springs, which tend
| to force the pole in verticle position. The
| trolley stand, which holds the pole Is set
| on turning frame, which gives it the re-
volVng motion necessary to follow the troll
| ley wire in going around curves. The con-
| tact of the trolley wheel and wire must be
| constant and thorough. The trolley wheel
| is connected by a bearing with a wire which
| passes down the pole to the car roof, and
/ following a trouth or groove comes out to q
| switch under the bonnet in front of the car
over the motorman's head; from there il
| passes to the reverse end of the car through
| another switch over the conductors head
| IL then goes down and connects with the
| controlling device. The controlling device
| varies with manufacturers. There are sew
| eral different kinds in use on our roads
| One is known as the series parallel or null
| tiple controller. This be used only
Is also a controller known as the rheostat
| The rheostat is made of material which
| offers resistance to an electric current. Ii
| being known that certain materials alb
| solute insulatorS and that other materials
| are only fair conductors. The rheoStat is sc
| arranged that more or less of the reSistanc.
| conductor is inserted between the trolley
| wire and the motor. The less reSistanc,
| there is the more current will reach the mo-
| tor and the faster the car will travel and
| the controlling device, which the motor mar
| uses with his left hand, is connected with
| the rheostat for the purpose of regulating
! the contacts. The current after passing
| through the rheostat or controller pass a:
| through the motor; from the positive pol.
/ of the motor through the motor to the axle
| of the car, through the axle to the wheel
| 10 the rail, from the rail through the bono
A.. nd Nxir IN rhea