Electric Utility Terms, Utility terms glossary, Electric glossary, Glossary of electric terms

Electric utility terms speaks to utility terms glossary, electric glossary and glossary of electric terms.

Electric terms and a definition of electric components which comprise building electric systems.

Bus way

A bus way is a raceway consisting of elbows, tees, crosses and straight runs. It contains conductors which are supported by insulators.

Structure Insulators

Includes bus work, insulators, meter transformers bushings and fuses within the transformer vault.

Load Break Switches

These are devices which are equipped with make and break mechanisms, arcing and mains contacts as well as arc-quenchers to deal with load and fault currents to protect operating personnel.

Electric Utility Terms

Cables, Primary and Secondary Feeders

These are devices and products used within the transformer and substation. Included are primary and secondary feeders, primary air break, oil break switches, primary lightning arrestors and high tension fuses.

Circuit Breaker

This is an electromechanical device designed to open a current carrying circuit under both overload and short circuit conditions without breakdown of the device. This applies to devices designed to trip on a preset over amperage. Common types are relays, dash pots, current transformers, tripping and other devices used for the operation of circuit breakers.


This is an electrical device which is used to generate and electrical magnetic field known as EMF.

Electric Utility Terms

DC Generator

This is an electrical device that is designed to generate a direct current using armature and brushes.


This is a device which consists of two conducting surfaces separated by an insulator and having the ability to store electrical energy.

Capacitor Bank

This device is a transient volt and surge protector which consists of a group of capacitors connected in parallel to provide a constant desired Kilowatt amperage.

Electric Utility Terms

Voltage regulator

A transformer device whose voltage ratio of transformation can be adjusted.


This is a device which produces alternating current energy.


These may be electrical or electronic control devices which are used for building and process control.


This is also known as an isolating switch which is designed to electrically isolate equipment from the power source.

Harmonic trap

This device is used to provide protection for the electrical system and other connected equipment from an unbalanced power supply or operating condition.

Main disconnect

This is simply the main switching device which can be used to disconnect a building from the main electrical source.

Electric Utility Terms

Distribution panel

This is a single panel including buses with or without switches, automatic over current devices, other equipment for the control of light, heat or power circuits and is constructed as a complete unit.

Panel board

This is used to feed lighting and appliance branch circuits and is defined as that which has more than 10% of its over current devices rated 30 amperes or less, for which a neutral connection is provided.

Distribution splitter trough

This is an enclosure which contains terminal plates or bus bars having main and branch connectors.

Electric Utility Terms

DDC control cabinet

These are cabinets which hold DDC boards and control modules designed for the most part to monitor and control building HVAC mechanical systems.

Distribution switchboard

This will be a panel or assembly of panels on which is mounted any combination of switching, measuring, controlling and protective devices, buses and connections. This is designed to deal with carrying and rupturing the maximum fault current encountered when controlling incoming and outgoing feeders.

Electric heaters

These are electric heat elements which are installed in ducts and are used to raise the temperature of the supply air upon demand.

Electric baseboard heater

These are used to provide individual room heat, which are installed at floor level along the perimeter.

Emergency lighting

This is a system which has an independent power supply, usually an emergency generator that upon disruption of the normal power supply automatically engages to provide illumination for egress from the building and supplies power to essential services and work areas.

Outside lighting

This system consists of outdoor lighting fixtures and standards, including associated wiring and equipment such as underground or overhead wiring, panel boards, transformers, switches, time switches, photoelectric switches. These all form part of the electrical service and is the source of supply for and to the lighting fixtures and lamps.

Lightning Rod

This is a device which is designed to protect buildings and circuits from electrical interference by grounding of the electrical current.

Metering equipment

Devices that are used to measure the amount of electricity that a building uses. It may also integrate flow, temperature and pressure from transmission devices into energy values.

Motor Control Center

This MCC is a switchboard which contains starters at a central location to protect and start and stop motors at various locations.

Automatic transfer switch

This electrical switch transfers power under load either from commercial power to emergency power or the reverse.

Oil filled transformer

This is an electromagnetic device which transfers electrical energy from the primary circuit into variations of voltage in secondary circuits.

Dry transformer

This is an electromagnetic device which transfers electrical energy from the primary circuit into variations of voltage in secondary circuits.

Transformer vault

This is a secured room specifically designed to hold major electrical components such as main breakers, bus, transformers and all other related equipment. It will include fans and associated cooling, ventilating equipment as required.

Underground electrical services

This service would include all types of electrical services that that are distributed underground which includes manholes, pulpits, cables, conductors as well as associated equipment.

Exterior sub station

This station is where electricity is transformed to lower voltage to be transferred to a network.

Explain Building Electric

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