How to Measure Electricity Consumption

Step 1

Purchase a simple watt-hour meter. These devices can be found at most hardware stores or larger department stores.

Step 2

Plug the electronic device you which to measure into the watt-hour meter.

Step 3

Plug the watt-hour meter into the wall.

Step 4

Read the meter. The watt-hour meter will measure the electrical output of the electronic device. The longer the device remains plugged into the meter, the more accurate the result.

Step 1

Locate the electrical meter on the outside of your home. The meter usually is on the side or the very back of the house. The meter is mounted onto the house and is at least 4 to 5 feet from the ground.

Step 2

Determine the kH factor for your electric meter. The kH factor for analog meters with silver discs is 7.2 kH. For digital meters, the kH factor is 1.0. This information will be found on the meter itself, generally below the readout.

Step 3

Decide how many "beats" you plan to measure to figure consumption. A "beat" is the number of seconds it takes to record one unit of measure on the electric meter. For example, for analog meters, when the disc makes one complete revolution, that sequence is one "beat." On digital meters, when the meter reading increases by one, that is a "beat." The more beats measured, the more accurate the consumption measurement.

Step 4

Choose either the "Read Once" or "Read Twice" method. The "Read Once" method requires you to unplug everything but the device you are measuring, but you only have to read the meter once. The "Read Twice" method only requires you to unplug the device you intend to measure, but requires reading the electrical meter more than once.

Step 1

Unplug all electrical devices, including air conditioners and refrigerators.

Step 2

Plug in the device you want to measure.

Step 3

Measure the beats on the electric meter using the method selected in Section 2, Step 3.

Step 4

Write this number down as part of your calculation.

Step 1

Turn on the device whose consumption you intend to measure. Unplug any device that might start suddenly, such as an air conditioner, furnace or refrigerator. If these devices turn on while you are measuring, they will compromise the accuracy of the measurement.

Step 2

Get a reading from the electric meter using the method selected in Section 2, Step 3.

Step 3

Return to the device being measured, and unplug the device.

Step 4

Repeat the measurement method at the electric meter used in Step 2.

Step 5

Compute the consumption for the device using the following equation: 3600 x # of beats / # of seconds x kH factor For the Read Once measurement, the answer to the equation is the consumption. For the Read Twice Method, subtract the second reading from the first to determine the consumption.