60. The use of electricity for supplying heat for cooking is very
popular in some homes, especially those which are properly wired,
because of its convenience and cleanliness and the fact that the heat it
produces can be applied direct. The first electrical cooking apparatus
was introduced at the time of the World's Fair in Chicago, in 1892, and
since that time rapid advancement has been made in the production of
suitable apparatus for cooking electrically. Electricity would
undoubtedly be in more general use today if it were possible to store it
in the same way as artificial gas, but as yet no such method has been
devised and its cost is therefore greater. Electricity is generated in
large power plants, and as it is consumed in the home for lighting and
cooking it passes through a meter, which indicates the quantity used in
much the same manner as a gas meter. It will be well, therefore, to
understand the way in which an electric meter is read, so that the bills
for electricity can be checked.
61. READING AN ELECTRIC METER.--An electric meter, which is similar in
appearance to a gas meter, consists of three or four dials, which are
placed side by side or in the shape of an arc. In the usual type, which
is shown in Fig. 2 and which consists of four dials placed side by side,
each one of the dials contains ten spaces and a hand, or indicator, that
passes over numbers ranging from to 9 to show the amount of
electricity used.
[Illustration: Fig 2.]
The numbers on the dials represent _kilowatt-hours_, a term meaning the
energy resulting from the activity of 1 kilowatt for 1 hour, or 1 watt,
which is the practical unit of electrical power, for 1,000 hours. Since
1,000 hours equal 1 kilowatt, 1,000 watt-hours equal 1 kilowatt-hour. It
will be observed from the accompanying illustration that the dial on the
extreme right has the figures reading in a clockwise direction, that is,
from right to left, the second one in a counter-clockwise direction, or
from left to right, the third one in a clockwise direction, and the
fourth one in a counter-clockwise direction; also that above each dial
is indicated in figures the number of kilowatt-hours that one complete
revolution of the hand of that dial registers.
To read the meter, begin at the right-hand dial and continue to the left
until all the dials are read and set the numbers down just as they are
read; that is, from right to left. In case the indicator does not point
directly to a number, but is somewhere between two numbers, read the
number that it is leaving. For example, in Fig. 2, the indicator in the
right-hand dial points to figure 4; therefore, this number should be put
down first. In the second dial, the hand lies between and 1, and as it
is leaving 0, this number should be read and placed to the left of the
first one read, which gives 04. The hand on the third dial points
exactly to 6; so 6 should be read for this dial and placed directly
before the numbers read for the first and second dials, thus, 604. On
the fourth and last dial, the indicator is between 4 and 5; therefore 4,
which is the number it is leaving should be read and used as the first
figure in the entire reading, which is 4,604.
After the reading of the electric meter has been ascertained, it is a
simple matter to determine the electricity consumed since the last
reading and the amount of the bill. For instance, assume that a meter
registers the number of kilowatt-hours shown in Fig. 2, or 4,604, and
that at the previous reading it registered 4,559. Merely subtract the
previous reading from the last one, which will give 45, or the number of
kilowatt-hours from which the bill for electricity is computed. If
electricity costs 3 cents a kilowatt-hour, which is the price charged in
some localities, the bill should come to 45 X .03 or $1.35.