Glossary
Glossary of Common Electrical Facilities Terms
Amps
Unit of measurement of electric current.
Applicant / Customer
Residential: Individual who requests service at a dwelling for his or her own residential use, or the residential use by another person.
Nonresidential: An individual, corporation, or other entity requesting service from the company that is not a residential applicant.
Anchor
Rod that provides a solid point of attachment in the ground for a guy wire.
Backboard
On a pole-mounted electrical service, such as those for a mobile home or travel trailer, the backboard is attached to the service pole and provides a surface for the meter enclosure to be secured. Backboards must be treated, painted or pressure treated.
Bonding Screw
Screw that physically connects neutral bus to the panel box.
Building
Structure which stands alone or is separated from adjoining structures by approved fire walls with all openings protected by approved fire doors.
Bus Bar
Energized metal strip inside the panel box, which has blade-style connectors to which the circuit breakers attach and become energized.
Bushing
Threaded circular ring that screws onto the end of the conduit to protect the wires from sharp edges of conduit.
Circuit Breaker
Acts as an automatic switch to shut the power off when too much current is flowing through a circuit. Once a circuit breaker opens, it must be reset before power can be restored.
Circuit Breaker Box or Fuse Box
Metal box that houses circuit breakers or fuses. Also called panel box.
Clearance
Required separation mandated by codes or the company.
Conductor
Wire that carries or conducts electricity. Conductor is either covered or bare, and is normally aluminum or copper.
Conduit
Metal or plastic pipe used to protect electric wires, either underground or above the roof line, if additional height is needed at the point of attachment.
Cost and Expense
Cost of all materials and equipment, labor and other definite charges, engineering, purchasing, the use of construction equipment, and other costs of a general character, associated with the work to be performed.
Couplings
Used to connect two separate pieces of conduit.
Current
A term for the electricity moving through wires. Measured in amperes (amps).
Distribution
Refers to circuits, equipment, and construction where voltage has been “stepped down” from transmission voltages to 35,000 volts or lower, to be utilized by the average consumer.
Distribution Line
Electric facilities constructed along a road to serve one or more customers.
Easement
Right granted by a property owner for the specific use of a defined area of said owner’s property.
Electricity Service
The conductors and equipment for delivering energy from the company’s line to the customer's wiring system (service point).
Electrical Inspector
Inspectors who are approved by the municipality where they are working and by the company, and are responsible for ensuring installations comply with all applicable codes and company requirements, service equipment, material, installations, and/or procedures.
Entrance Cable
The covered wire (usually gray/black) that goes from the top of the pole to the meter for a pole-mounted meter, or down the side of the house if the meter is on the house. Located on the lower side of the meter enclosure that connects the customer’s panel and the load side of the meter.
Fuse
A device used to protect electrical equipment from short circuits. Fuses are made with metals that are designed to melt (or blow) when the current passing through them is too high. When the fuse melts, the electrical connection is broken, interrupting power to the circuit or device.
Ground
Conducting connection between an electrical circuit or equipment and earth.
Ground Lug
Common point of attachment for neutral circuit wires inside the panel box.
Ground Rod
Metal rod, usually copper, that is driven into the ground, which provides a means to attach the service ground wire to.
Ground Rod Clamp
Clamp that is used to securely connect the service ground wire to the ground rod.
Guy Wire
Braided steel wire used to hold conductor strain on poles. Attaches from the top of the pole to the anchor.
House Hook
A hook that screws into a solid portion of the building to provide an attachment point for CMP's service cable. This hook may also be referred to as a service drop hook.
House Knob/ Service Knob
A porcelain insulator, attached to the house where the overhead service wires are connected.
Insulator
A material or object through which an electrical current cannot pass, or passes with difficulty. Some common insulators are rubber, porcelain and air.
Jumper
"Slack” electrical connection between two points. Also, a mechanical jumper that may be used temporarily to maintain continuity of electric service.
Lag Bolt
A threaded, metal hex-head bolt that provides solid attachment to wood.
Line
A system of poles, wires and fixtures (overhead), or the equivalent ducts, conduits, cable, etc. (underground), used for general distribution of electricity.
Mast Kit / Pipe Riser
When the point of attachment is lower than company standards allow, a mast kit is used to provide additional height over the roofline. In this type of installation, the mast must be galvanized metal conduit. The use of plastic pipe would not be able to support the weight of the service cable. All masts must be guyed.
Meter, Electric
Device used to measure and record the amount of energy used by a customer. The type of meter is determined by the customer's service classification and rate.
Meter Enclosure / Meter Box / Meter Socket
A square metal box with a removable cover and apparatus inside that accepts and houses the electric meter.
Meter Types
Meters are self-contained or current transformer rated, straight, off-peak, demand, time of use or reactive.
Mobile Home
A mobile home is a factory assembled structure equipped with the necessary service connection, made to be readily movable as a unit on its own running gear, and designed to be used as a dwelling unit without a permanent foundation.
Multi Meter/Modular Metering
When several meter enclosures are attached together, multi meter/modular metering is used mainly for apartment buildings, malls and offices.
Overhead
A type of electrical line construction where all conductors, transformers and other electrical devices are mounted on poles.
Padmount Transformer
Transformer that is installed on a cement pad for underground service. It reduces high voltage to 120/240 volts.
Panel Box
A metal rectangular box that is energized from the meter enclosure. This houses the circuit breakers, or fuses and is the distribution point for electricity in the home or business.
Pedestal
A short wooden pole, buried in the ground, and used to support the metering equipment for underground service.
Permanency
A structure will be considered permanent when it is connected to an approved permanent sewer and water system and is in compliance with local zoning laws.
Phase
This term refers to the number of wires in a circuit, either single-phase (two energized conductors) or three phase (three energized conductors). Three-phase service offers more versatility to nonresidential or industrial customers. Generally single-phase service is for residential customers.
Point of Attachment
The location of the service drop conductors to a building or structure provided by the customer. The company requires the point of attachment to be installed prior to providing service.
Pole
A post, usually pressure treated timber or cedar. Also known as a "telephone pole," or utility pole.
Pole-Mounted Transformer
The transformer mounted on a pole which reduces or "steps down" primary distribution voltage for use by individual customers.
PVC Conduit
This is a type of plastic pipe that can be used to provide protection to electric cables. It must meet standards of the National Electric Code and Utility Construction Standards.
Premises
A house or building and its land.
Regulator
Monitors voltage in a circuit and “steps down” or “steps up” the voltage to the required level.
Right of way
Land acquired for the construction and operation of an electric, or some other, facility. It may be owned outright or an easement may be taken for a specific purpose. The right of ingress and egress over and/or to the easement.
Rigid PVC
This is a type of plastic pipe that can be used to provide protection to electric cables. It must meet standards of the National Electric Code as well as CMP Construction Standards..
Riser
The portion of a system (secondary or primary wires) which transitions between above-grade (pole mounted) and below-grade service.
Riser Cable / Entrance Cable
Cable on the top side of the meter that feeds from the line side of the meter enclosure up the building to the point of attachment.
Service
The conductors and equipment for delivering energy from the electricity delivery system to the wiring system of the premises served.
Service Cable Clips / Riser Clips
Metal clips used to secure a service entrance cable to the side of a building.
Service Connection
A service connection is one service drop or lateral and its associated service entrance.
Service Drop
The overhead service conductors between the company’s last pole or other aerial support, and the customer’s first point of attachment to the building or other structure of the premises being served.
Service Entrance
That part of the installation from the point of attachment or termination of the service drop or lateral to and including the service equipment on the customer’s premises.
Service Entrance Cable
Cable that runs from the meter enclosure up the side of the building to the point of attachment.
Service Entrance Conductors
The service conductors or cables which extend from the point of attachment or termination of the service drop or lateral to the terminals of the service equipment.
Service Lateral
A system of underground conductors and equipment for delivering electricity from the company’s electricity delivery system to the wiring system of a building or premises.
Service Line
Electric facilities constructed off-road to serve only one customer.
Service Pole
Generally a wooden pole used to support electrical service equipment. The pole must meet National Electric Code Standards and Utility Construction Standards.
Short Circuit
A condition in which resistance is reduced so far as to allow high current to flow in the circuit. An electrical fire or arc often results.
Single-Phase Line
A conductor installation carrying electrical loads capable of serving the needs of residential customers, small business customers and street lights.
Stand-Off Bracket
A bracket used to support conduit away from a pole when more than one conduit of the same utility is required.
Temporary Service
Service to be used for a limited time (normally not to exceed one year) for construction, exhibits, decorative lighting or similar purposes, or service to non-permanent structures. A temporary wooden structure that is constructed to support electric service equipment during the construction of a home or business.
Three-Phase Line
A conductor installation capable of carrying heavy loads of electricity, also called poly phase.
Trailer Pole
This is generally a wooden pole used to support electrical service equipment in a pole-mounted service. This pole must be of a certain size and type of wood, as well as be of adequate length to provide necessary height. The pole must meet CMP Construction Standards, as well as National Electric Code Standards.
Transformer
Device that changes voltage from one level to another, either up or down.
Transformer Bank
A group of either two or three transformers, wired together, to provide service to nonresidential and industrial, three-phase customers.
Trench
A ditch that is excavated to Utility Construction Standards in which underground wires will be installed from one point to another.
U Clamps
Clamps that fasten conduit to a pole or building.
UD (Underground Distribution)
The terminology used to describe the underground placement of the company’s electricity delivery system.
URD (Underground Residential Distribution)
The terminology used to describe the underground placement of the company’s electricity delivery system (except transformers and switchgear) and customer’s service laterals in residential developments.
Voltage
Pushes current through wires. Measured in volts or kilovolts (1,000 volts).
Weatherhead
A small cap that is attached to the building which provides weatherproof protection at the point where the service cable from utility’s pole attaches to the service entrance cable. The service entrance cable runs from the meter enclosure to the weatherhead and attaches to the company's service cable.
Wire Size
Conductor is measured in terms of American Wire Gauge (AWG).