The Glasgow courier. [volume] (Glasgow, Mont.) 1913-current, 1917-04-13
kILOWATT U

klLOWAIT HOUKS.
A term which means nothing to
many householders using electricity
although it is the standard of cleo
trical measurement for selling cleo.
trio light and power.
"Kilowatt hours" are what the av.
erage consumer of electric energy
pays for when the bill is rendered
, each month, yet there are thousands
of h~ouseholders paying electric bills
who have no idea of what this sim.
pie unit of electrical measurement,
means. The reason for this is be-
cause the average man has no con
ception of how it is possible to meas.
ure a power which has no finite di-
mansions, and which nc physicist has
ever defined in an acceptable way. 1t
is easy for him to imagine what a
cubic foot of gas is, because of the
fact that it must be stored in con-
tainers just like potatoes or coal and
is piped from place to place like wa
ter.
A motorist knows that a gallon of
gasoline of a certain standard of test
will carry him a certain number of
miles and also that he can count on
an average number of miles to the
gallon with a fair degree of accur-
acy. The kilowatt hour is just as
definite a quantity to the electrician
as the gallon Of gasoline is to the
motorist, with the distinction that
electricity cannot be ad~ulterated or
stored and that the tendency in prices
of electric service has been revision
downward instead of upward. 1t must
be produced as it is used and the
unit of measurement, the kilowatt
hour, represents a definite amount
of work that one watt of electrical
energy will do in one hour. Kilo,
derived from the Greek, means one
thousand. Therefore the kilowatt
hour is the amount of work one watt
will do working for one thousand
hours. Measured with the average
watthour meter used by all central
stations it is as definite a quantity
of energy as a gallon of gasoline,
with the difference that the average
house electric meter measures cleo
tricity with a precision which varies
rarely more than two or three per
cent. The error is also usually in the
customers favor, although the accur-
acy of the meter is periodically
checked by a meter tester and kept
within as small a fraction of error as
is humanity possible.
The Meter a Jeweled Electric Motor.
The watthour meter installed in
electrically lighted homes is really
nothing more than a tiny electric mo-
tor built like a watch with jeweled
bearings and just as carefully pro-
tected against dust with a dust-proof
iron cover. Only a small part of the
current used passes through the US
ual house meter, but this is sufficient
to rotate a copper or aluminium disk
which is pivoted in a magnetic field.
The disk is geared through a train
Of tiny gear wheels to the pointers
on the Celebrated dial. The meter is
so connected in the housekeeping cir
cult that it only operates when cur
rent is being used and of course it's
speed of rotation is in direct proper
ton to the amount of electricity that
is being drawn through it. A Mazda
lamp consuming but 10 watts, for ex-
ample, will draw such a small guam
tity of current that the movement of
the aluminium disk is hardly precep-
tible. A carbon lamp giving the same
amount of light, but consuming about
80 watts, three times as much cleo
tricity, will at once accelerate the
rate of speed of the rotating disk in
the meter, affording a striking ex-
ample of the economy IF Mazda
lamps.
How to Read Your Meter.
Barring homes where the older
type Of meters are used, most house
lighting circuits receive electricity
from the central station through a
G-E direct reading kilowatt hour me-
ter. These instruments have "Kilo-
watt hours" plainly printed on the
dial. Starting at the left the four
dials indicate respectively, tens of
thousands, thousands, hundreds, and
tens of kilowatts. In making a read
ing it is only necessary to read each
dial in the order named carefully not
ing the direction of rotation on each
dial and putting down only the figure
last indicated. This should be done
once each month, the reading noted
and the reading the subsequent month
s%ubtracted from it. For example sup
pose the reading on January l We're
5O64 and on February l the reading
was 5O86. %Subtracting the first read
ing from the second leaves %, the
number of kilowatts used during the
month intervening. At the usual rate
Of 10 cents per kilowatt the bill for
the month would then be 1920. Where
the bill appears to be excessive it is
a good plan to make readings every