Definition of terms Flashcards
Admitting close approach; not guarded by locked doors, elevation, or other effective means.
Accessible (as applied to equipment)
Capable of being removed or exposed without damaging the building structure or finish or not permanently closed in by the structure or finish of the building.
Accessible (as applied to wiring methods)
Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, and so forth
Accessible, Readily (Readily Accessible)
The current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Ampacity
Utilization equipment, generally other than industrial, that is normally built in standardized sizes or types and is installed or connected as a unit to perform one or more functions such as clothes washing, air conditioning, food mixing, deep frying, and so forth.
Appliance
Acceptable to the authority having jurisdiction.
Approved
A generic term for a group of nonflammable synthetic chlorinated hydrocarbons used as electrical insulating media. Askarels of various compositional types are used. Under arcing conditions, the gases produced, while consisting predominantly of noncombustible hydrogen chloride, can include varying amounts of combustible gases, depending on the askarel type.
Askarel
A device that, by insertion in a receptacle, establishes a connection between the conductors of the attached flexible cord and the conductors connected permanently to the receptacle.
Attachment Plug (Plug Cap) (Plug)
The organization, office, or individual responsible for approving equipment, materials, an installation, or a procedure
Authority Having Jurisdiction (AHJ)
Self-acting, operating by its own mechanism when actuated by some impersonal influence, as, for example, a change in current, pressure, temperature, or mechanical configuration.
Automatic
The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.
Bonding (Bonded)
A reliable conductor to ensure the required electrical conductivity between metal parts required to be electrically connected.
Bonding Jumper
a set of conductors that extends beyond the last overcurrent device protecting the circuit and the outlet(s).
Branch Circuit
A device designed to open and close a circuit by non-automatic means and to open the circuit automatically on a predetermined overcurrent without damage to itself when properly applied within its rating
Circuit Breaker
Indicating that the circuit breaker can be set to trip at various values of current, time, or both, within a predetermined range.
Adjustable
- No delay is purposely introduced in the tripping action of the circuit breaker.
Instantaneous Trip
There is purposely introduced a delay in the tripping action of the circuit breaker, which delay decreases as the magnitude of the current increases.
Inverse Time
It does not have any adjustment to alter the value of current at which it will trip or the time required for its operation.
Nonadjustable
The value of current, time, or both, at which an adjustable circuit breaker is set to trip.
Setting
Rendered inaccessible by the structure or finish of the building. Wires in concealed raceways are considered concealed, even though they may become accessible by withdrawing them
Concealed
A conductor having no covering or electrical insulation whatsoever.
Conductor, Bare
A separate portion of a conduit or tubing system that provides access through a removable cover(s) to the interior of the system at a junction of two or more sections of the system or at a terminal point of the system. Boxes such as FS and FD or larger cast or sheet metal boxes are not included.
Conduit Body
- A device that establishes a connection between two or more conductors or between one or more conductors and a terminal by means of mechanical pressure and without the use of solder.
Connector, Pressure (Solderless)
A load where the maximum current is expected to continue for 3 hours or more.
Continuous Load
A device or group of devices that serves to govern, in some predetermined manner, the electric power delivered to the apparatus to which it is connected.
Controller
Conductors drawn from a copper-clad aluminum rod with the copper metallurgically bonded to an aluminum core. The copper forms a minimum of 10 percent of the cross- sectional area of a solid conductor or each strand of a stranded conductor.
Copper-Clad Aluminum Conductors
An enclosure designed for surface mounting that has swinging doors or covers secured directly to and telescoping with the walls of the box proper
Cutout Box
Without live parts exposed to a person on the operating side of the equipment.
Dead Front
The ratio of the maximum demand of a system, or part of a system, to the total connected load of a system or the part of the system under consideration.
Demand Factor
A device, or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply.
Disconnecting Means
Constructed so that dust will not enter the enclosing case under specified test conditions.
Dusttight
Operation at a substantially constant load for an indefinitely long time.
Continuous Duty
Operation for alternate intervals of (1) load and no load; or (2) load and rest; or (3) load, no load, and rest.
Intermittent Duty
- Intermittent operation in which the load conditions are regularly recurrent.
Periodic Duty
Operation at a substantially constant load for a short and definite, specified time.
Short-Time Duty
Operation at loads, and for intervals of time, may be subject to wide variation.
Varying Duty
Surrounded by a case, housing, fence, or wall(s) that prevents persons from accidentally contacting energized parts
Enclosed
The case or housing of apparatus, or the fence or walls surrounding an installation to prevent personnel from accidentally contacting energized parts or to protect the equipment from physical damage.
Enclosure
Electrically connected to a source of voltage.
Energized
Capable of being inadvertently touched or approached nearer than a safe distance by a person. It is applied to parts that are not suitably guarded, isolated, or insulated.
Exposed (as applied to live parts)
On or attached to the surface or behind panels designed to allow access.
Exposed (as applied to wiring methods)
- All circuit conductors between the service equipment, the source of a separately derived system, or other power supply source and the final branch-circuit overcurrent device.
Feeder
A string of outdoor lights that is suspended between two points.
Festoon Lighting
An accessory such as a locknut, bushing, or other part of a wiring system that is intended primarily to perform a mechanical rather than an electrical function
Fitting
A device intended for the protection of personnel that functions to de-energize a circuit or portion thereof within an established period of time when a current to ground exceeds the values established for a Class A device.
Ground-Fault Circuit Interrupter (GFCI)
A conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode or electrodes.
Grounding Conductor
The conductor used to connect the non-current-carrying metal parts of equipment, raceways, and other enclosures to the system grounded conductor, the grounding electrode conductor, or both, at the service equipment or at the source of a separately derived system.
Equipment Grounding Conductor
A device that establishes an electrical connection to the earth.
Grounding Electrode
The conductor used to connect the grounding electrode(s) to the equipment grounding conductor, to the grounded conductor, or to both, at the service, at each building or structure where supplied by a feeder(s) or branch circuit(s), or at the source of a separately derived system.
Grounding Electrode Conductor
Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers, casings, barriers, rails, screens, mats, or platforms to remove the likelihood of approach or contact by persons or objects to a point of danger.
Guarded
An enclosure identified for use in underground systems, provided with an open or closed bottom, and sized to allow personnel to reach into, but not enter, for the purpose of installing, operating, or maintaining equipment or wiring or both.
Handhole Enclosure
- Any shaftway, hatchway, well hole, or other vertical opening or space in which an elevator or dumbwaiter is designed to operate.
Hoistway
Where this Code specifies that one equipment shall be ―in sight from,‖ ―within sight from,‖ or ―within sight,‖ and so forth, of another equipment, the specified equipment is to be visible and not more than 15 m (50 ft) distant from the other.
In Sight From (Within Sight From, Within Sight)
The highest current at rated voltage that a device is intended to interrupt under standard test conditions.
Interrupting Rating
Conductor or conductive part intended to be energized in normal use.
Live Parts
Locations protected from weather and not subject to saturation with water or other liquids but subject to moderate degrees of moisture. Examples of such locations include partially protected locations under canopies, marquees, roofed open porches, and like locations, and interior locations subject to moderate degrees of moisture, such as some basements, some barns, and some cold-storage warehouses.
Damp Location
A location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction.
Dry Location
Installations underground or in concrete slabs or masonry in direct contact with the earth; in locations subject to saturation with water or other liquids, such as vehicle washing areas; and in unprotected locations exposed to weather.
Wet Location
A complete lighting unit consisting of a lamp or lamps together with the parts designed to distribute the light, to position and protect the lamps and ballast (where applicable), and to connect the lamps to the power supply
Luminaire
A type of surface, flush, or freestanding raceway designed to hold conductors and receptacles, assembled in the field or at the factory.
Multioutlet Assembly
Action requiring personal intervention for its control. As applied to an electric controller, non-automatic control does not necessarily imply a manual controller, but only that personal intervention is necessary.
Non-automatic
A point on the wiring system at which current is taken to supply utilization equipment.
Outlet
Any current in excess of the rated current of equipment or the ampacity of a conductor. It may result from overload, short circuit, or ground fault.
Overcurrent
Operation of equipment in excess of normal, full-load rating, or of a conductor in excess of rated ampacity that, when it persists for a sufficient length of time, would cause damage or dangerous overheating. A fault, such as a short circuit or ground fault, is not an overload.
Overload
A single panel or group of panel units designed for assembly in the form of a single panel, including buses and automatic overcurrent devices, and equipped with or without switches for the control of light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a wall, partition, or other support; and accessible only from the front.
Panelboard
A compartment or chamber to which one or more air ducts are connected and that forms part of the air distribution system.
Plenum
An enclosed assembly that may include receptacles, circuit breakers, fuse holders, fused switches, buses, and watt-hour meter mounting means; intended to supply and control power to mobile homes, recreational vehicles, park trailers, or boats or to serve as a means for distributing power required to operate mobile or temporarily installed equipment
Power Outlet
An enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables, or busbars, with additional functions as permitted in this Code. Raceways include, but are not limited to, RMC, RNMC, IMC, LFC, FMT, FMC, ENMT, EMT, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways, and busways.
Raceway
Constructed, protected, or treated so as to prevent rain from interfering with the successful operation of the apparatus under specified test conditions.
Rainproof
Constructed or protected so that exposure to a beating rain will not result in the entrance of water under specified test conditions.
Raintight
is a contact device installed at the outlet for the connection of an attachment plug. A single receptacle is a single contact device with no other contact device on the same yoke. A multiple receptacle is two or more contact devices on the same yoke.
Receptacle
An outlet where one or more receptacles are installed.
Receptacle Outlet
The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.
Service
Service conductors made up in the form of a cable.
Service Cable
The conductors from the service point to the service disconnecting means
Service Conductors
The overhead service conductors from the last pole or other aerial support to and including the splices, if any, connecting to the service-entrance conductors at the building or other structure.
Service Drop
The service conductors between the terminals of the service equipment and a point usually outside the building, clear of building walls, where joined by tap or splice to the service drop.
Service-Entrance Conductors, Overhead System
The service conductors between the terminals of the service equipment and the point of connection to the service lateral.
Service-Entrance Conductors, Underground System
- The necessary equipment, usually consisting of a circuit breaker(s) or switch(es) and fuse(s) and their accessories, connected to the load end of service conductors to a building or other structure, or an otherwise designated area, and intended to constitute the main control and cutoff of the supply
Service Equipment
The underground service conductors between the street main, including any risers at a pole or other structure or from transformers, and the first point of connection to the service-entrance conductors in a terminal box or meter or other enclosure, inside or outside the building wall. Where there is no terminal box, meter, or other enclosure, the point of connection is considered to be the point of entrance of the service conductors into the building.
Service Lateral
The point of connection between the facilities of the serving utility and the premises wiring
Service Point -
Any window used or designed to be used for the display of goods or advertising material, whether it is fully or partly enclosed or entirely open at the rear and whether or not it has a platform raised
higher than the street floor level.
Show Window
Any electric circuit that energizes signaling equipment.
Signaling Circuit
- An automatic or non-automatic device for transferring one or more load conductor connections from one power source to another.
Transfer Switch
A large single panel, frame, or assembly of panels on which are mounted on the face, back, or both, switches, overcurrent and other protective devices, buses, and usually instruments. Switchboards are generally accessible from the rear as well as from the front and are not intended to be installed in cabinets
Switchboard
A protective device for assembly as an integral part of a motor or motor-compressor that, when properly applied, protects the motor against dangerous overheating due to overload and failure to start.
Thermal Protector (as applied to motors)
Equipment that utilizes electric energy for electronic, electromechanical, chemical, heating, lighting, or similar purposes.
Utilization Equipment
A flammable liquid having a flash point below 38°C, or a flammable liquid whose temperature is above its flash point, or a Class II combustible liquid that has a vapor pressure not exceeding 276 kPa at 38°C and whose temperature is above its flash point.
Volatile Flammable Liquid
The greatest root-mean-square (RMS/effective) difference of potential between any two conductors of the circuit concerned.
Voltage (of a circuit)
A nominal value assigned to a circuit or system for the purpose of conveniently designating its voltage class (e.g., 120/240 volts, 480Y/277 volts, 600 volts). The actual voltage at which a circuit operates can vary from the nominal within a range that permits satisfactory operation of equipment.
Nominal Voltage
For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit.
Voltage to Ground
Constructed so that moisture will not enter the enclosure under specified test conditions
Watertight
Constructed or protected so that exposure to the weather will not interfere with successful operation
Weatherproof
The service conductors between the terminal of the service equipment and point usually outside the building, clear of building walls, where joined by a taps or splices to the service drop. A building or other structure served be supplied by one service only
Service Entrance
the underground service conductors between the street main including any risers at a pole or other structure or from transformers, and the first point of connection to the service-entrance conductors in a terminal box or other enclosure, inside or outside the building wall. Where there is no terminal box, meter, or other enclosure, the point of connection is considered to be the point of entrance of the service conductors into the building.
Service Lateral
A device that, when interrupting currents in its current-limiting range, reduces the current flowing in the faulted circuit to a magnitude substantially less than that obtainable in the same circuit if the device were replaced with a solid conductor having comparable impedance.
Current-Limiting Overcurrent Protective Device
A conductor, other than a service conductor, that has overcurrent protection ahead of its point of supply that exceeds the value permitted for similar conductors that are protected.
Tap Conductor
An intentionally constructed, permanent, low-impedance electrically conductive path designed and intended to carry current underground-fault conditions from the point of a ground fault on a wiring system to the electrical supply source and that facilitates the operation of the overcurrent protective device or ground fault detectors on high-impedance grounded systems.
Effective Ground-Fault Current Path
An unintentional, electrically conducting connection between an ungrounded conductor of an electrical circuit and the normally non-current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth.
Ground Fault
An electrically conductive path from the point of a ground fault on a wiring system through normally non-current carrying conductors, equipment, or the earth to the electrical supply source.
Ground-Fault Current Path
connects the equipment grounding conductors, the service- equipment enclosures to the grounding electrode(s)
Grounding Electrode Conductor
Any metal underground water pipe 3000 mm or more and electrically continuous to the points of connection of the grounding electrode conductor and the bonding conductors.
Metal Underground Water Pipe
3000 mm or more of a single structure metal member in direct contact with earth or encased in concrete that is in direct contact with the earth.
Metal Frame of the Building
An electrode encased by at least 50 mm of concrete located near the bottom of concrete foundation or footing. It has 6000 mm of one or more electrically conductive steel coated bars.
Concrete Encased Electrode
Bare copper conductor not smaller than 30 mm2 encircling the building/structure. 6000 mm or more in length and buried at a depth not less than 750 mm
Ground Ring
A protective device for limiting surge voltages by discharging or bypassing surge current, and it also prevents continued flow of follow current while remaining capable of repeating these functions.
Surge Arrester
A protective device for limiting transient voltages by diverting or limiting surge current; it also prevents continued flow of follow current while remaining capable of repeating these functions.
Transient Voltage Surge Suppressor (TVSS)
A complete system of air terminals, conductors, ground terminals, interconnecting conductors, arresters, and other connectors or fittings required to complete the system.
Lighting Protection System
Generic terms for the component parts.
Rods and Points
Capable to drawing lighting discharge to it in preference to vulnerable parts of the protected area. It may consist of a pointed, solid, or tubular rod or one with special design and material provided with a mounting base having a proper conductor connection.
Air Terminal
All conductors, fittings, and fixture for protection not exceeding 23 m in height.
Class I Materials
All conductors, fittings and fixtures for protection exceeding 23 m in height; or one which has a structural steel frame, of any height.
Class II Materials
Steel with a coating of copper to bond it
Copper-Clad Steel
A conductor encircling a building and inter-connecting all ground terminals
Counterpoise (ground)
An attachment to secure the conductor to the structure
Fastener
Self-closing gage hatches, vapor seals, pressure-vacuum breather valves, flame arresters, or other reasonably effective means to minimize the possibility of flame entering the vapor space of a tank.
Flame Protection
The vapors given from a flammable liquid at or above its flash point.
Flammable Vapors
The minimum temperature at which it gives off vapor in sufficient concentration to form an ignitable mixture with air near the surface of the liquid within the vessel.
Flash Point
A building over 23m in height.
High-Rise Building
Metal objects at the flat roof level subject to direct lighting stroke.
Metal Body of Conductance
Metal objects located 2000 mm of a conductor subject to buildup of potential.
Metal Body of Inductance
Building with either sides or roof made of or covered with sheet metal.
Metal-Clad Building
Building with electrically continuous framing of sufficient size and conductivity.
Metal-Framed Building
