Electrical Glossary: A Detailed Glossary of All Electrical Terms

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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

[L]

 

 

Limit Switch:

A switch that is operated by some part or motion of a power-driven machine or equipment to alter the electric circuit associated with the machine or equipment.

 

 

 

Liquid-Filled Transformer:

A transformer in which the core and coil are immersed in a liquid which acts as both a cooling and insulating medium.

 

 

 

Live Parts:

Electric conductors, buses, terminals, or components that are uninsulated or exposed and an electric shock hazard exists.

 

 

 

Load:

The load of a transformer is the power, in kVA or volt-amperes, supplied by the transformer.
(Lagging Load) inductive type load.
(Leading Load) capacitive load.

 

 

 

Loadbreak:

The ability of a switching device to disconnect a load current without damage.

 

 

 

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.

 

 

 

Load Curve:

A curve showing instantaneous demand (kVA or MVA) versus time. Curves are usually plotted for one day or one week. Integrating the load curve will provide the amount of energy consumed.

 

 

 

Load Factor:

Represents how efficiently the electrical system capacity is being used. The higher the load factor the higher the efficiency.

 

 

 

Load Switching:

Transferring the load from one source to another.

 

 

 

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.

 

[M]

 

 

Metal Enclosed:

Surrounded by a metal case of housing, usually grounded.

 

 

 

Metalclad:

Devices in which the conducting parts are entirely enclosed in a metal casing.

 

 

 

Motors:

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

 

[N]

 

 

National Electrical Code (NEC):

A code/guideline used for the safeguarding of people and property from hazards related to the use of electricity. Compliance with this code along with proper maintenance will result in an installation essentially free from hazard. Abbreviated NEC. The NEC was first developed in 1897 as a result of the efforts of various insurance, electrical, architectural, and allied interests. It is sponsored and regularly updated by the National Fire Protection Association.

 

 

 

Neutral:

The junction point of the legs in a Wye circuit.

 

 

 

Neutral Grounding Resistor:

A grounding device, the principal element of which is resistance, which is used to connect the neutral point of the transformer to earth.

 

 

 

Normal Duty:

A lightning impulse classifying current category for distribution class arresters defined by ANSI/IEEE C62.11. A normal duty rated arrester has 5000 amperage impulse value crest