Power System Definitions
Circuit: The completed path traveled by an electric current.
Circuit Breaker: The automatic switch that interrupts a circuit when the electric current passing through it is too strong.
Distribution Line: One or more circuits of an electric system on the same line of poles or supporting structures (or underground facilities) operating at 13,000 volts or less.
Fault: A failure of an electric power line.
Fuse: A safety device that melts and breaks the current when too strong of a current is flowing.
Grounding: Connecting an electrical current to the ground, giving current a place to safely escape; the third wire on most electrical wires is the ground wire.
Insulator: Any material that will not conduct electricity, such as rubber or glass.
Lightning Arrestor: A device that can reduce the voltage of a power surge by passing the surge current to a ground. It's capable of interrupting a fault and restoring the current to original operating conditions.
Phase: The indication of electricity's voltage at any given point within its cycle. If the electricity alternates at the same time, it is operating in a single-phase system, such as that found in homes.
Relay: An electrically operated device for closing and opening a circuit to protect service from interruption or to prevent or limit damage to equipment.
Service Drop: The wires or cable running from the utility pole to the customer's home/business.
Short: An accidental connection joining two sides of a circuit and sharply increasing the flow of electricity beyond the limits of the conductor.
Transformer: An electromagnetic device for increasing or decreasing electrical voltage.
Transmission Lines: Wires or cables through which high voltage electric power is moved; a line used to transport electric energy from a source of supply (generating station or receiving point) to other principal parts of the system (major substations or delivery points).
Undergrounding: The placing of wires, cables and transformers under the ground.
Volt: A unit of electrical pressure; the force at which electrical charges move through conductors. In the United States, 120 volts is standard.