Residential electric meter.
A load meter is a device commonly found on electric meters installed by utility companies. The primary function of this meter is to indicate the maximum electricity usage since the monitor was last read, typically to determine if there have been any power spikes in the last month that would invalidate other readings. Homeowners can also use technology to determine ways to reduce energy and when the vast majority of electricity use occurs. Some load meters also have a separate gauge that measures the current voltage (amps) being drawn from the grid in real time, making it easy to keep track of energy conservation levels.
There are two different types of load meters installed throughout the world; mechanical and electronic. Mechanical load gauges are usually round, with a glass case around their perimeter, and next to the face there will be multiple dials giving multiple readings. The largest dial on this type of system is the actual load reading and will point to a certain number that is measured in kilowatts (megajoules). If the dialing is between two numbers, the dealer will record the lower of the two. Some mechanical load meters have a large, usually red, second display that indicates the current energy being consumed by the home.
An electronic load gauge works exactly the same way, in principle, but instead of multiple dials, all the information is displayed on a small digital screen. This type of meter transmits a weak signal that utilities can receive from several hundred yards or meters away, eliminating the need to physically inspect load meter boxes unless tampering is anticipated. The downside to this type of load meter is that the display is simply a number that is often unrelated to weekly or monthly usage, so it means little to the consumer when trying to estimate or track usage.
Consumers can also purchase an individual load meter to track their energy usage more efficiently. These devices have a standard electrical connector that allows any current-operated household item to be plugged in, and the readout display can be programmed to track energy use by the hour, day, or month. By reviewing each of the major appliances in the home, consumers will better understand which items consume the most energy and how to control their use more efficiently. Some of these personal load meters are even pre-programmed with information on which current appliance models are consuming energy for comparison purposes, making it easy to decide when to upgrade.