Ampacity: refers to the maximum current, in amperes, that a conductor can carry three hours or more without exceeding the temperature rating of the electrical insulation.

Amperage: the volume (or quantity) of electrical current flowing through a circuit. The volume is measures in amperes, otherwise known as amps.

Balancing or Load Balancing: a planning practice in which the total amperage requirements of the electrical equipment in a shared-neutral installation is distributed equally among the number of available circuits servicing the installation.

Ballast: a device in fluorescent lamps that regulates the level (amps) of electrical current and voltage flowing through the fluorescent lamp tube. Ballasts may be magnetic or electronic, with electronic being slightly more energy efficient.

Branch Circuit: A single circuit carrying electrical current, it consists of conductors (wires) connected between the building’s electrical service panel (circuit breakers) and the electrical outlets (power receptacles).

Circuit: a complete path for electrical current flowing from the building power source to the equipment being powered and back to the power source. The “hot” conductor of a circuit carries the power to the equipment; the “neutral” conductor carries it back to the source and the “ground” conductor provides a safe escape route for the power in the event of short circuits or other problems.

Circuit Breakers: a safety device designed to automatically stop the flow of electricity whenever a circuit becomes overloaded, i.e. exceeds the number of amps that the wiring can accommodate.

Codes, Local Electrical Codes: Various government bodies have adopted minimum safety standards, or “codes” for electrical wok. The National Electrical Code (NEC) is the most widely recognized code, and it applies to most installations. Municipalities, city, counties and townships can have their own electrical codes.

Common Ground: An electrical circuit that uses a variety of conductors for a ground path.

Conduit: Metal or non-metallic tubing, either rigid or flexible used to route and protect electrical wires and communication cables.

Dedicated Circuit: a circuit with three conductors – hot, neutral and ground, between the circuit breaker protecting the branch circuit and the outlet that is dedicated only for use with specific equipment.

Designated Branch Circuit: a branch circuit with three conductors – hot, neutral and ground, that is designated by the user for use with specific equipment. Either the neutral and ground or both, may be shared with another branch circuit.

Ground Conductor: the conductor of a circuit that provides safety from fire and electrical shock in cases of short circuits and other electrical problems.

Ground Fault Circuit Interrupter, GFI, or GFCI: shuts off a circuit instantly if it senses a hazardous short.

Hot Conductor: the conductor that carries current from the power source to the equipment.

Isolated Ground: Serves the same safety and protection function as a common ground conductor, but it is run in a separate “isolated” conductor.

Junction Box: an electrical construction box that provides a space for the connection or “splicing” of electrical conductors.

Load: describes the amount of power (amps) consumed by an electrical circuit or device.

Low Voltage System: a wiring system that provides power to some electronic devices operating at a lower voltage lever than the standard 110 volts. Examples include lights, doorbells, and thermostats.

Maximum Continuous Load: the maximum electrical current in a circuit expected to be in constant use for three hours or more. For safety reasons load must not exceed 80% of the maximum electrical rating.

National Electrical Code (NEC): a set of minimum standards and regulations that governs planning, construction and installation of electrical conductors and equipment.

Neutral Conductor: the conductor that carries current back to the power source.

Ohm: Ohm is the measure of electrical resistance or impedance in a circuit. One volt will cause one amp to flow through one ohm of resistance.

Open Circuit: a condition where the current flow through a conductor is interrupted by a missing or damaged component.

Panel, Load Center: source for all power to the home, all circuits originate from this piece of equipment, this is where your circuit breakers are located.

Polarized Plug, Grounded Plug, 3-Prong Plug: a plug designed to be inserted into a receptacle in one position only.

Receptacle: provides one point of access to the branch circuit with places to plug in one, two or three cords.

Short Circuit: a condition in which the hot conductor comes in contact with the ground or neutral conductor. A short circuit causes a spark or arc that often damages one or both of the circuit components and causes the circuit breaker to trip.

Smoke Detector and Carbon Dioxide Detectors: Wall and ceiling mounted sensors located throughout the home used to alert occupants of deadly gases and smoke inside the home.

Surge Protector: an electrical device that protects equipment from a sudden, high fluctuation in the level of voltage normally flowing during a period of time.

Switch: Circuit interruption devices used to control the flow of electricity to lights, appliances and devices.

Wattage, Watts: the amount of power used by an electrical device. Wattage can be calculated by multiplying voltage and amperage.

Definitions adopted from Haworth Booklets on Electrical Topics www.haworth-furn.com