El Paso herald. (El Paso, Tex.) 1901-1931, 1912-12-27
As To Electricity
Explanation of Some of the Things
That the Average Individual
Does Not Know.
. LECTRICITY is a IA more defi- /


! - power. The public has learned
from constant repetition that about 30
| percent of the energy liberated Oy
| burning coal 10 run a steam engine
/ is wasted. In an electrical machine,
] the waste is far less and the amount
/ Of energy that IS generated can be
1 measured far more accurately.
Electric generators are machines to
| transform mechanical power into cleo
/ tricaI power. In other words. they
! generate electric current when driven
] by mechanical power. They are run
/ by steam engines, turbines. gas en-
! glneS or some ether form of mechanl-
! cal power called prime movers" The
! generator is constructed to transform
/ the amount of mechanical power that
/ the prime mover running it supplies.
| A generator run by a 10 horse power
/ engine, for instance, will transform 10
horse power of energy, less a small
percentage (about 10 percent) lost in
/ the process. Electrical engineers
| don't usually say that a generator
transforms 10 horse power. Their
measure of energy cor power) is the
kilOwatt, which is equal to one and
third horse power. So they say that
the generator transforms seven and
half kilowatts, which is the equivalent
change In nomenclature be any more
confusing than to say that one inch
is equal to two and a half centimeters?
Electricity Is Simple.
Mention the action of electric cur
rent to a neOphyte, and he Immediately
assumes a look of blank perplexity.
Yet the fundamental facts about cleo
trio current are extremely simple. An
electric current will not move unless
1t can move in a complete circuit and
get back where II came from. This
is why it is safer Tor a man handling
an electric current to work with one
hand behind his back He is then not
likely to touch 1t in two places and
thus complete circuit through him
self An electric current acts physical
~ like one continuous piece of ma
terial, such as a hoop or an endless
chain, one part of which, win not
move unless the whole of it moves
You cannot revOlve one part Of a
hoop without revolving the whole hoop.
You cannot move one part of an
endless chain without moving the
whole chain In telegraphing from
New York to Chicago, the action OF
electric current is precisely similar to
what ii would be if you had a long
chain reaching this distance and back,
and you pulled upon it Internationally
to make the dots and dashes. Only,
instead of pulling on the chain, you
break and Close the electric curcuit.
This can be done at any point along
the line, and the effect is apparent at
any other place or at any number of
places simultaneously Sometimes
the return part OF the chain is Oy
a second electric wire, and sometimes
the return is made through the earth.
When the circuit is broken at any
point on the line the current stops
everywhere, to start again when the
break is closed.
How the Current Knows.
But how does the current in New
York know that the circuit is broken
in ChicagO2 This brings US to one OF
the really remarkable fact about cleo
trio current It travels at the rate of
mil
speak, 'See ahead" this distance, when
Is longer than any electric circuit
that has ever been used. So an cleo
trio current stops in less than sec
ond if the circuit is broken anywhere
within 100000 miles OF where the cur
rent is generated.
That an electric generator of 10
horse power capacity run by a 10 horse
power engine will transform 10 horse
power of mechanical energy into 10
horse power, or seven and a half kilO-
watts, of electricity with practically no
less, IS true of a direct current gener-
ator' but in an alternating current
generator larger carrying capacity is
required for the following reason:
Electric power is the product of the
volume of current (amperes) and the
pressure at which it flows (vOIts)
Just as the energy with which water
flows out of a pipe is the result of
the volume of water and the pressure
at which it is flowing. The product
Of the amperes and volts is called
watts. When the product is 1000 C0G
volts ty 10 ampercs, or 10 volts BY
100 amperes, for instance) it is called
one kilOwatt.
An Alternating Current.
In an alternating current machine !
the amperes and volts reverse their
direction with marvellous raDiditv- but
not always at the same instant The
ampereS may arrive at a motor which
IS being run by the generator slight
" before the volts or pressure. In
tnat case, the amperes with no voltage |
behind them are idle and do not pro- |
duce any power. Put the generator,
the motors and the transmission lines I
IN fact all parts of the system, have /
to be made large enough to carry all /
companied by volts and therefore 1
produce power or not. The idea can be !
best expressed by a smile. Imagine /
a man in business on borrowed capi- |
IaI, VINO expects to make a certain /
percentage a year on the commodity /
he sells, providing he sells it promptly. /
SuppoSing he cannot sell it promptly
he has to pay interest on the capital |
invested in his stock This cuts down !
his net profits. The failure of the 1
pressure CvOlts) to reach the motor at |
the same time as the volume of cur 4
rent (amperes) cuts down the amount J
Of power delivered by the machine in (
precisely the same way as the slow !
sales cut down the profits of the bust /
ness man.
If Volts Are Wrong.
II the volts cUun5 a little bit later J
or earlier than the amperes so that !
20 percent of the amperes are not &C (
cOmpanied by volts this reduction is 1
20 percent and the machine, or sys- !
tenn, is said to have only so percent |
power factor. Therefore a generator |
with so percent power factor would /
have to be big enough to transmit /
the current corresponding to u IL |
horse power in order to transform all /
the power from 10 horse power en- |
CINE. Twenty percent of the u - |
horse power capacity, or 2 1-2 horse /
power, is idle capacity. The remaining |
10 horse power are transformed. and |
the generator, by being built large |
enough to transmit u IL horse power, |
succeeds in transmitting the full OUT |
put of the engine running ito horse |
power.
HISTORIC ALE HOUSE TO