UTILITY EMERGENCIES April 2014 Flashcards
(98 cards)
The flow of an electric current across a gap between two conductors, terminals, or contacts. An ___ can result in sparks, a loud noise, and a momentary or sustained outage as protective equipment operates. An ___ is capable of creating large amounts of heat and light.
pg 1
arc
___ – Short for circuit breaker, a component that detects overload conditions and then disconnects and stops the flow of electrical current to protect and ensure safe operation of the system.
pg 1
Breaker
___ – Acronym for boiling liquid expanding vapor explosion.
pg 1
BLEVE
___ – A path through which electric current is intended to flow. A circuit originates from a central point and extends out to serve customers.
pg 1
Circuit
___ – Located at the top of a utility pole, a wooden bar to which power lines are attached, keeps the lines separated by a sufficient distance to prevent arcing.
pg 1
Cross Arm
___ – The electric distribution system links the transmission system to most customers, includes primary and secondary lines.
pg 1
Distribution System
___ – In an electrical power system, a fault is any abnormal electrical current. For example, a short circuit is a fault in which the current exceeds the normal load. An open circuit fault occurs when some type of failure interrupts a circuit.
pg 1
Fault
___ – A protective device, consisting of a conducting material, which melts and burns opening the circuit when a specified value is exceeded. When melted or blown, the flow of electricity is interrupted to prevent damage to equipment. The temporary disruption of a blown fuse that creates an outage until the fuse is replaced is far better than the type of extended outage that results when equipment is damaged and needs to be replaced. Fuses also limit the number of customers that are affected by the outage.
pg 1
Fuse
___ – Designed to be incapable of producing heat or spark sufficient to ignite an explosive atmosphere.
pg 1
Intrinsically Safe
___ – Actions taken to reroute power around a particular area, leaving it isolated from an energy source while repairs are made.
pg 2
Isolate
___ – Abbreviation for 1,000. (For example, 12 kV = 12,000 volts, 500 kV = 500,000 volts).
K
___ – An electrical outage lasting two minutes or less.
pg 2
Momentary Outage
___ – A device, which provides transition between underground cable to overhead lines or conductors.
pg 2
Pothead
___ – Electric service delivered between 2,000 and 50,000 volts to a distribution transformer, which, in turn, reduces voltage to secondary levels.
pg 2
Primary
___ – An automatic protection device that senses and interrupts distribution system faults.
pg 3
Recloser
___ – The conductor part of transition leading from underground to overhead; may or may not include pothead.
pg 3
Riser
___ – Electric service taken at less than 2,000 volts. Most residential and business customers receive electricity from secondary distribution lines.
pg 3
Secondary
___ – The process of opening switches or fuses to divide a circuit into sections to isolate the cause of the power outage. This reduces the impact of the power outage to the fewest possible customers by allowing power to move through undamaged parts of the system.
pg 3
Sectionalize
___ – A quarter-turn valve used to restrict or isolate the flow of liquid or gas in a pipe.
pg 3
Stopcock Valve
___ – A location, which uses a collection of transformers to reduce voltage and circuit breakers to protect circuits.
pg 3
Substation
___ – An electrical outage that lasts for more than two minutes.
pg 3
Sustained Outage
___ – A device for making, breaking, or changing connections with in an electric circuit.
pg 3
Switch
___ – The process of opening and closing switches to isolate an area from the flow of electricity.
pg 3
Switching
___ – The average exposure to a contaminant or condition (such as noise) to which workers may be exposed without adverse effect over a period such as in an 8- hour day or 40-hour week.
pg 3
Time Weighted Average (TWA)



