Ampere - The unit of measurement of electrical current produced in a circuit by 1 volt acting through a resistance of 1 ohm.



Alternating Current (AC) - Electric current which changes direction with a regular frequency.

American Wire Gauge - A standard measure which represents the size of wire. The larger the number, the smaller the wire. Abbreviated AWG.

Capacitor - A device that stores electrical charge usually by means conducting plates or foil separated by a thin insulating layer of dielectric material.

Btu (British Thermal Unit) - A standard unit for measuring the quantity of heat energy equal to the quantity of heat required to raise the temperature of 1 pound of water by 1 degree Fahrenheit.

Grid - In an electrical system, a term used to refer to the electrical utility distribution network.

Fishing Box - In a conduit system of wiring, a name sometimes given to a junction box at which splices may be made and wires may be "fished" through.

Feeder - A circuit, such as conductors in conduit or a busway run, which carries a large block of power from the service equipment to a sub-feeder panel or a branch circuit panel or to some point at which the block power is broken into smaller circuits.

Incandescent Light Bulbs - Incandescent light bulbs produce light by passing electricity through a thin filament, which becomes hot and glows brightly.

Interrupter - An element designed to interrupt specific currents under specified conditions.

Overload - Load greater than the load for which the system or mechanism was intended. A fault, such as a short circuit or ground fault, is not an overload.

Overcurrent - Any current in excess of the rated current of equipment or the ampacity of a conductor. It may result from overload, short circuit or ground fault.

Frequency - In alternating current, the rate at which the current changes direction. One complete cycle is a unit of 1 Hertz. The standard frequency in the US is 60 Hz.

Real Power - The rate at which work is performed or that energy is transferred. Electric power is commonly measured in watts or kilowatts. The term real power is often used in place of the term power alone to differentiate from reactive power.

Transient - A high amplitude, short duration pulse superimposed on the normal voltage.