Chapter 5 - Electrical Knowledge Flashcards
____ is a measure of electrical force, similar to pressure in the hydraulic model
Volt
A disruption of electrical supply is called an ______
interruption
Electromotive force is also called
voltage
_____ _____ (_____) is the difference in electrical energy between an energized conductor and another energized conductor, the ground, or other object
Electrical potential (voltage)
____ is a measure of current
Amp or Ampere
One ___ is the charge carried by 6.25 x10to the 18th electrons moving past a given point in one second
Amp
Amperage is ____ on a particular circuit, depending on demand.
variable
As demand ____ on a circuit, amperage ____
increases, increases
____ is a measure of electrical power
Watt
___ are calculated by multiplying volts and amps
Watts
A million watts is called a ______
Megawatt
______ is opposition to the current flow, analogous to friction or drag.
Resistance
Resistance is measured in ____
Ohms
Measure of electrical resistance consisting of one volt flowing at one amp
Ohm
_____ is the sum of resistance- inductive resistance and capacitive resistance
Impedence
______ reactance is caused by a small amount of load lost when a current flows into a coal (such as transformers)
Inductive
_____ reactance is a charge that builds up between long parallel conductors, which hinders current
Capacitive
_____ is the capacity of a material to transmit electricity
Conductivity
Materials with ____ conductivity have ____ resistance to electricity
high, low
_____ is an electrical network consisting of a conductor or series of conductors through which electricity flows, including a return path to the source
Circuit
A power _____ is a sustained service interruption
Outage
_____ are amperages in a conductor that are large than those for which is rated
Overcurrents
A _____ is a bypass of an intended conducting path
fault
_____ current is the amperage of the resulting abnormal electrical flow
Fault
Current that is bypassing a designed conducting path is called a ______ ______
short circuit
_______ faults affect the dielectrical properties of a system for an instant, and no longer exist after the power has been restored.
Transient
______ faults are repeated momentary interruptions in the same place due to to the same cause
Intermittent
_____ _____ are inrushes of electricity. They often occur when circuits are first re-energized following an outage
Current Surges
_____ is the electrification of a wire by passing it through a moving electromagnetic field
Inductance
_______ _____ is a force field comprising electric and magnetic elements associated with electric charge in motion
Electromagnetic field
An energized conductor or wire in a circuit is called a ______
phase
_____ ______ ____ _____ _____ (_____) is a system that automatically collects data and enables remove control switching operations
Supervisory Control and Data Acquisition (SCADA)
____ is a electric facility equipped with transformers, switching equipment, and protection and control devices. Voltage is changed here.
Substations
Region where transmission or extra-high transmission lines are connected.
Transmission Interconnect
The ______ ______ allows utilities to transfer electricity both within their systems and among one another. It enables power delivery to areas of greatest demand
Transmission Interconnect
The value derived from, or a subset of the System Operating Limits, which if exceeded, could expose to a widespread area of the Bulk Electric System to instability, uncontrolled separations, or cascading outages
Interconnection Reliability Operation Limit (IROL)
____ enable utilities to route power through various circuits as needed
Switchyards
An electric facility that does not change voltage, but is used to route power through various circuits.
Switchyard
High voltage lines generally energized between 69 and 161 kV. Connect bulk transmission substations to industrial customers or distribution substation
Subtransmission lines
The portion of an electrical utility system that delivers electricity to end-users.
Distribution Network
In an electric utility system, electric supply lines usually energized between 2.4 and 23kV
Distribution Lines
In distribution systems, a simple design with only one path of power flow, consisting of a single track of three-phase lines from a substation, with three or single-phase laterals tapping off them to serve end-users
Radial System
True or False: Radial systems are straightforward and inexpensive, the layout provides no backup source of power for customers
True
_____ ______ system joins two radial circuits together with an open switch, which can be closed during a power outage
Loop Radial
A ___ ____ ___ is made up of one circuit that begins at a substation and returns to the same substation. It maintains power automatically when there is a fault
Loop Primary circuit
A ___ is a stationary part of an electrical generator. Contains the field windings
Stator
Magnets are spun on their axes, exposing field windings in a generator to alternating positive and negative magnetic poles, which provide the movement necessary to induce _______ _____ into the coil
Electromotive Force
_____ ____ ( ) is the electric current that reverses its direction many times per second at regular intervals, typically used in power supplies
Alternating Current (AC)
The changing intensity and direction of alternating current is graphed in a ____ _____
Sine Wave
The time it takes for a magnet to complete a revolution is a ______
Cycle
The number of cycles per second in alternating current is measured in
Hertz
Smooth grid functioning requires electrical generation to by synchronized at the _____ ______
same frequency
______ _____ is the most common source of renewable generation
Hydroelectric Generation
Aluminum has gained favor for conductors due to:
light weight
low cost
Aluminum conductors have ____ conductivity than copper
lower
Energized cable constructed from an aluminum wire stranded around a steel core; minimizes the tendency of alumninum to stretch when heated and adds strength
Aluminum conductor (core) steel-enforced cable
Type of coated overhead primary wire used on distribution lines in densely forested areas
Tree Wire
_____ wires connect an electrical circuit or equipment to the earth or some conducting body that serves in place of the earth. There is no difference in potential and no shock hazard.
Neutral
____ wires are the common return path for an electrical circuit or physical connection to the earth
Ground
____ wires work by providing a low resistance fault return path to the power source, and help facilitate proper over current device operation during a ground fault
Neutral
Type of distribution construction consisting of three phases and a grounded or neutral wire. The phases have polarity, creating a voltage differential among them
Wye construction
Type of distribution construction configuration with three phases, but no common neutral wire. There is no fixed difference between the phase-to-phase and phase-to-ground voltages
Delta construction
A distribution secondary line that carries electricity from a transformer to a home or business
Service drop
A lower voltage electric supply line that carries electricity from distribution transformers to service line
Secondary wire
A type of secondary wire, which has two insulated conductors and a neutral wrapped around a supportive cable
Triplex
Guy wires are intended for ______, rather than electrical conduction, but are conductive.
support
The activation of a protection device in an electric transmission or distribution system is called
Operation
Transmission Circuit breakers operate in response to what 3 types of irregularities?
- ) abnormally high amperage
- ) abnormally low voltage
- ) unequal current in 3 phases
____ is the wire connection between energized conductors and other electrical equipment, such as transformers.
Taps
____ ______ are the principal protective devices in both distribution and transmission substations
Circuit Breakers
____ is a permanent operation that requires manual closure of automatic line reclosers
Lock Out
A transient fault in an electrical system is called a _______ ________. They may result when an automatic recloser fails to operate
Transient Fault