Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

autotransformer starter
a single three-phase autotransformer or three single phase transformer used to start induction motors at a reduced voltage.
auxiliary relay
a relay employed in power system protection schemes that does not directly sense fault presence and location. Typical auxiliary relays include lockout relays, reclosing relays, and circuit breaker anti-pump relays.
auxiliary winding
a winding designed to be energized occasionally for a specific purpose, such as starting a single-phase motor. The power to the winding may be controlled by various means including a timer, centrifugal switch, current sensing relay, or voltage (counter EMF) sensing relay.
average power
the average value, taken over an interval in time, of the instantaneous power. The time interval is usually one period of the signal.
average-value model
a mathematical representation in which the average value of variables are used to model a system. In electric machines and drives, system variables are typically averaged over various switching intervals. This eliminates the high-frequency dynamics, but preserves the slower dynamics of the system.

See automatic voltage regulator
American Wire Gauge, a system of wire sizing used in the USA especially in smaller conductors used in residential and
commercial wiring.