Electrical Glossary


Alternating Current (AC)



Ampere or Amps

A unit of measurement for electrical current flow in a conductor. I=E/R


Appliance (Fixed)

An appliance that is fastened or otherwise secured


Appliance (Portable)

An appliance that can easily be moved.


Appliance (Stationary)

An appliance that is not easily moved from one place to another


Balanced Load

An alternating current power system of more than two current carrying conductors which all carry the same current.



The connection of two or more points to reduce any difference of potential


Branch Circuit

The circuit conductors between the final overcurrent device protecting the circuit and the outlets.


Circuit Breakers / Fuses

Devices installed in the service panel of a home to limit the flow of electricity through a circuit. The breaker rating determines the maximum flow.


Circuit Extensions

To extend or add-on to an existing circuit to provide an additional power source.


Code Corrections

Procedure designed to eliminate wiring conditions that do not meet National Electrical Code requirements and safety conditions.


Continuous Load

A continuous load is a load where the maximum current is expected to continue for 3 hours or more.



The flow of electrons through a conductor. Measured in amperes.


Direct Current (DC)

Flows in the same direction. (e.g., batteries)


Distribution Equiptment

A device designed to provide electricity to multiple connections.


Duplex Receptacle

This is wired into an outlet box. And will allow you to plug in two electrical devises.



A metalic tubular raceway used for carrying wires


Energy Saving Devices

Devices utilized within a dwelling designed to more efficiently make use of energy sources while providing heating, cooling, and light.



Any permanently connected light or other electrical device that consumes power.


Flat Stanley

The main character of a 1964 childrens book (ISBN 0-06-009791-4) by Jeff Brown

Book Synopsis:

Stanley Lambchop is flattened when a big bulletin board (which Dad gave Stanley and his younger brother, Arthur for putting pictures and posters) falls on him as he sleeps. He lives and soon is sliding into rooms under closed doors, being a kite, solving crimesand travelling in a large envelope.



Removable devices that link a circuit at the fuse box. Fuse connections blow apart and break the circuit if an overload or short occurs.


GFI (Ground Fault Interrupter)

A device whose function is to break the electrical circuit to the load when there is a fault current to ground.



Connected to earth or to some conducting body that serves in place of the earth.


Grounded Conductor

A system or circuit conductor that is intentionally grounded.


Grounding Conductor

A conductor used to connect equipment or the grounding circuit of a wiring system to a grounding electrode or electrodes.


Hazardous Locations

A location where fire or explosion hazards may exist to flammable gases, vapors, liquids, dust or fibers.



A heat source (gas or electric) used to adjust the temperature inside a dwelling from a cold to a warm condition.



An inverter takes DC power from a 12-volt battery and converts it to household AC power.



A joule is a measurement of electrical energy. 1 joule is equal to 1 watt of power for 1 second of time (watts x time = joules).


Junction Box

A metal or plastic box used to enclose splice connections.


Load Center

Source for all power to the home. All circuits originate from the \"Load Center\" or \"Service Panel.\" Circuit breakers are located within this panel.


Low Voltage

A wiring system that provides power to some electronic devices operating on a voltage level much lower than the standard 110 volts. Such devices might be doorbells and thermostats.



To convert Amps to Millamps multiply by 1000 (.055 Amps = 55 Milliamps).



Electronic device used to move, switch, or adjust one or more of the systems within a dwelling.



The unit of measurement for electrical resistance. R=E/I.


OHM\'s Law

E=IR, or I=E/R, or R=E/I. E=voltage, I=current, and R=resistance.


Open Ground

The wire grounding your electrical devices has been disconnected.



A point on a wiring system at which current is taken to supply electrical devices. A receptacle is placed in an outlet.


Parallel Ciruit

In parallel circuits the components are so arranged the current divides between them. The voltage remains the same but the current may vary. The circuits in your home are wired in parallel.



A short, added piece of wire connected by a wire nut. Commonly used to extend or connect wires in a box.



Power sources located throughout a building to provide electricity where needed.



Is an object having resistance. A resistor is a conductor inserted into a circuit to introduce resistance.



Plastic coated cable. Has a soft flexible jacket. Used mainly for indoor wiring.


Series Circuit

A Series circuit is one in which all components are connected in tandem. The current at every point of a series circuit stays the same. In series circuits the current remains the same but the voltage drops may vary.



The conductors and equipment for delivering energy from the electricity supply system to the wiring system of the premises.


Service Point

The point of connection between the facilities of the serving utility and the premises wiring.


Servicer Main Panel

This is the panel that holds the branch circuit overcurrent protection devices that feed lighting and appliances. This panel also contains service entrance cables from the meter or disconnect.


Single Phase

A single output which may be center tapped for dual voltage levels.


Smoke and Carbon Dioxide Detectors

Wall and ceiling mounted sensors located throughout the home used to alert occupants of deadly gasses and smoke inside the home.



A short duration high voltage condition. May last for several cycles.



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



A low voltage electronic switching device that monitors temperatures inside the home and turns on and off the heating or cooling system in the home.


Three Phase Power

Three separate outputs from a single source with a phase differential of 120 electrical degrees between any two adjacent voltages or currents.


Track and Accent Lighting

Condition specific lighting that meets special lighting requirements, providing variable lighting degrees of light and may distribute light in multiple directions.


Transfer Switch

An electronic device that under certain conditions will disconnect from one power source and connect to another power source.


Two Gang Outlet Box

This is an outlet box that will allow you to use two electrical items ( two receptacles, two switches, or one of each). The more gangs the more devises.


Type U.F. Cable

This type of cable is used mostly for direct burial in the earth. This is a branch circuit cable that also can be used for outside wiring.



A unit that measures the amount of electrical pressure.E=IR.


Volt Amps

Amps is the term used to describe the flow of current. Volts is the electrical pressure applied to a circuit to make the current flow. The formula for power or watts is volts times amps. Volt Amps would be Watts.



A unit that measures the amount of electrical power. P=EI.



This is a slang name for a type of meter that reads voltages from 120 to 600 volts. This meter can be held in the palm of your hand and has a slight vibration when testing voltages.



A brand name for a raceway used to carry wires. This is exposed and is used mostly in public buildings and offices. It can be used in homes when it is not practical to run wires in walls.



A device used to connect spliced wires together.



A distribution network of wire that conducts electricity to receptacles, switches and appliances throughout a building/home to provide electricity where needed.