To understand how an electric meter works, you must first have a basic understand-
ing of electricity. Electric energy is measured in watts and metered and billed in kilo watt-hours. A watt equals the voltage multiplied by the amperage or current. If electric energy was a stream, the voltage would be the width and depth of the stream.
The amperage would be how fast the stream is flowing. Wattage is simply how much
water is in the stream at a given time. Watt-hours is how much water passes through
the stream in an hour’s time. For example, if a 120v electric motor draws 10 amps,
the connected load would be 1200 watts or 1.2 kilowatts. The motor would con-
sume 1.2 kWh over a one-hour period and 12 kWh over a ten-hour period.
Electric meters work very much like an electric motor. The energy entering the
home is passed through a set of small wires surrounding a shaft. The current passing through the wires creates an electric field that "induces" the shaft to turn. The shaft is connected to a graduated disk and a set of gears that turn an set of numbers much like an odometer in a car. A set number of revolutions of the large disk corresponds to one kilowatt-hour
Understanding Electric Meter
