Go Back to Article 1 Table of Contents
| New query |
The following definitions of frequently used terms shall be accepted as the intended meanings of these terms whenever used in these High-Voltage Electrical Safety Orders.
NOTE: Definitions of other terms used in only one article are included in the front of that article.
Accessible.
(A) Accessible (as applied to equipment). Admitting close approach because not guarded by locked doors (unless keys are readily available to those requiring access), elevation or other effective means. (See "Readily Accessible.")
(Title 24, Part 3, Article 100.)
(B) Accessible (as applied to wiring methods). Not permanently closed in by the structure or finish of the building; capable of being removed without disturbing the building structure, finish, or fixed appurtenance thereto. (See "Concealed" and "Exposed.")
(Title 24, Part 3, Article 100.)
(C) Readily Accessible. 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, chairs, etc.
(Title 24, Part 3, Article 100.)
(D) Safely Accessible. Not exposing persons installing, operating, maintaining, or inspecting electrical apparatus to serious risks of tripping or falling or of coming in contact with energized electrical parts, moving machinery, surfaces or objects operating at high temperatures, or other hazardous equipment.
Aerial Lift. A device used to raise workers to an elevated position.
Ambient Temperature. The temperature of the cooling medium that comes in contact with the device or equipment.
Ampacity. Current-carrying capacity of electric conductors expressed in amperes.
Apparatus Case. The case (or tank) of electrical apparatus is that part which serves as the container for the principal energized parts and insulating medium.
Askarel. 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 upon the askarel type.
Atmosphere.
(See Environment, also.)
(A) Contaminated Atmosphere. An atmosphere containing contaminants which tend to impair the effectiveness of electrical insulation.
(B) Corrosive Atmosphere. An atmosphere containing contaminants which react chemically with the parts of an electrical installation so as to impair its electrical conductivity and/or its mechanical strength.
(C) Explosive Atmosphere. (See Article 34.)
(D) Flammable Atmosphere. (See Article 34.)
Authorized Person. A qualified person delegated to perform specific duties under the conditions existing.
Automatic Circuit Recloser. A self-controlled device for automatically interrupting and reclosing an alternating current circuit, with a predetermined sequence of opening and reclosing followed by resetting, hold closed, or lockout operation.
(Title 24, Part 3, Article 3-100.)
Automatic Opening. (Tripping). The opening of a switching device under predetermined conditions without the intervention of an attendant.
(Title 24, Part 3, Article 3-100.)
AWG. American Wire Gauge.
Barricade. Physical obstruction such as tapes, screens or cones intended to warn and limit access to a hazardous area.
Barrier. Physical obstruction which is intended to prevent contact with energized lines or equipment.
(Title 24, Part 3, Article 3-100.)
Basic Impulse Level (BIL). (See Ratings.)
(Title 24, Part 3, Article 3-100.)
Bonding. The permanent joining of metallic parts to form an electrically conductive path which will assure electrical continuity and the capacity to conduct safely any current likely to be imposed.
(Title 24, Part 3, Article 100.)
Bonding Jumper. A reliable conductor to assure the required electrical conductivity between metal parts required to be electrically connected.
(Title 24, Part 3, Article 100.)
Branch Circuit. That portion of a wiring system extending beyond the automatic overcurrent protective device, excluding any thermal cutout or motor running overload protective device that is not approved for short circuit duty.
Bus.
(A) Isolated Phase Bus. One in which each phase conductor is enclosed by an individual metal housing separated from adjacent conductor housings by an air space.
(B) Non-Segregated Phase Bus. One in which all phase conductors are in a common metal enclosure without barriers between phases.
(C) Segregated Phase Bus. One in which all phase conductors are in a common metal enclosure but are segregated by barriers between phases.
(Title 24, Part 3, Article 3-100.)
Bushing. An insulating structure including a through conductor, or providing a passageway for such a conductor, with provision for mounting on a barrier, conducting or otherwise, for the purpose of insulating the conductor from the barrier and conducting current from one side of the barrier to the other.
(Title 24, Part 3, Article 3-100.)
BWG. Birmingham Wire Gauge.
Cable, Electrical. A stranded conductor (single-conductor cable) or a combination of conductors insulated from one another (multiple-conductor cable).
(Title 24, Part 3, Article 3-100.)
Cable Riser. (See Riser.)
Cable Sheath. A protective covering applied to cables.
NOTE: A cable sheath shall be permitted consist of multiple layers of which one or more is conductive.
(Title 24, Part 3, Article 3-100.)
Cable Terminations.
(A) Pothead. A device for the electrical and mechanical termination of an insulated electrical cable.
(B) Stress Cone. Cable termination which provides electrical stress relief for an insulated electrical cable.
(C) Terminal Chamber (Conduit Box). A separate compartment on electrical apparatus for terminating insulated electrical cables.
(D) Wiping Sleeve. A hollow, cylindrical, metal attachment to the tank (or case) or terminal chamber of electrical apparatus which is used for the mechanical termination of lead-sheathed insulated electrical cable.
(Title 24, Part 3, Article 3-100.)
Case (Tank). (See Apparatus Case.)
Circuit. A conductor or system of conductors through which an electric current is intended to flow.
Circuit Breaker. (See Switching Devices.)
(Title 24, Part 3, Article 100.)
Clearance (Authorization). Authorization to enter an area and/or to perform an ct restricted to authorized personnel.
Clearing Time. The time elapsing from the beginning of an overcurrent to the final circuit interruption.
(Title 24, Part 3, Article 3-100.)
Close and Hold. (See Ratings.)
(Title 24, Part 3, Article 3-100.)
Collector Ring. An assembly of slip rings for transferring electrical energy between a stationary and a rotating member.
(Title 24, Part 3, Article 3-100.)
Communication Lines. The conductors and their supporting or containing structures which are used for public or private signal or communication service, and which operate at potentials not exceeding 400 volts to ground or 750 volts between any two points of the circuit, and the transmitted power of which does not exceed 150 watts. When operating at less than 150 volts no limit is placed on the capacity of the system.
NOTE: Telephone, telegraph, railroad signal, data, clock, fire, police-alarm, community television antenna, and other systems conforming with the above are included. Lines used for signaling purposes, but not included under the above definition, are considered as supply lines of the same voltage and are to be so run.
Concealed. Rendered inaccessible by enclosures, raceways, structures, the finish of a building, etc.
(Title 24, Part 3, Article 3-100.)
Conductor. A wire, cable, or other conducting material suitable for carrying current.
(Title 24, Part 3, Article 3-100.)
Construction. The erection of new wiring and equipment, and the alteration, conversion, and improvement of existing wiring and equipment.
Contactor. A device for repeatedly establishing and interrupting an electric power circuit.
(Title 24, Part 3, Article 3-100.)
Contaminated. (See Atmosphere.)
Control.
(A) Automatic Control. An arrangement of electrical controls that provides for switching or otherwise controlling or both in an automatic sequence and under predetermined conditions the necessary devices comprising an equipment. These devices thereupon maintain the required character of service and provide adequate protection against all usual operating emergencies.
(B) Manual Control. Control in which the main devices, whether manually or power operated, are controlled by an attendant.
(C) Manual Operation. Operation by hand without using any other source of power.
(Title 24, Part 3, Article 3-100.)
Controller. A device, or group of devices, which serves to govern, in some predetermined manner, the electric power delivered to the apparatus to which it is connected.
(Title 24, Part 3, Article 100.)
Corrosive. (See Atmosphere.)
Current.
(A) Asymmetrical Current. The combination of the symmetrical and the direct current component of the current.
(B) Available (Prospective) Short Circuit Current (at a given point in a circuit). The maximum current that the power system can deliver through a given circuit point to any negligible impedance short circuit applied at the given point, or at any other point that will cause the highest current to flow through the given point.
(C) Excitation (Magnetizing) Current. The current supplied to unloaded transformers or similar equipment.
(D) Minimum Operating Current (of a relay or fuse). The minimum current that will cause a device to complete its intended operation.
(E) Overcurrent.
1. Fault Current (Short Circuit). A current that flows from one conductor to ground or to another conductor owing to an unintended connection (including an arc) between the two.
2. Overload Current. Any current (exclusive of fault current) in excess of rated current.
(F) Short-Time Current. (See Ratings.)
Cutout. (See Switching Devices.)
(Title 24, Part 3, Article 100.)
Dead. Free from any electrical connection to a source of potential difference and from electrical charges: Not having a potential difference from that of earth.
Dead-Front. So designed, constructed, and installed that no energized parts are normally exposed on the front.
(Title 24, Part 3, Article 3-100.)
De-energized Parts. Parts which have been previously energized and are now free from any electrical connection to a source of potential difference and from electrical charges.
Designated Employee. A qualified person delegated to perform specific duties under the conditions existing.
Dielectric Heating. The heating of a nominally insulating material due to its own dielectric losses when the material is placed in a varying electric field.
Discharge Device. A device intended for the dissipation of the energy stored in a disconnected inductive or capacitive device.
(Title 24, Part 3, Article 3-100.)
Disconnect (Isolator). (See Switching Devices.)
(Title 24, Part 3, Article 3-100.)
Disconnected Position (of a switchgear assembly removable element). That position in which the primary and secondary disconnecting devices of the removable element are separated by a safe distance from the stationary element contacts.
(Title 24, Part 3, Article 3-100.)
Disconnecting Means. (See Switching Devices.)
(Title 24, Part 3, Article 100.)
Division. Unless otherwise designated in this subchapter, the phrase "division" refers to the current Division of Occupational Safety and Health or any of its predecessors including the former Division of Industrial Safety or the Division of Occupational Safety and Health Administration. Reference to the former Division of Industrial Safety or Division of Occupational Safety and Health Administration in these orders is meant to refer to their successor, the Division of Occupational Safety and Health, or any subsequent successor agency.
Drawout Mounted Device. One having disconnecting devices and in which the removable portion may be removed from the stationary portion without the necessity of unbolting connections or mounting supports.
(Title 24, Part 3, Article 3-100.)
Dust-Proof. So constructed or protected that dust will not interfere with its successful operation.
(Title 24, Part 3, Article 3-100.)
Dust-Tight. So constructed that dust will not enter the enclosing case.
(Title 24, Part 3, Article 3-100.)
Duty.
(A) Continuous. A requirement of service that demands operation at a substantially constant load for an indefinitely long time.
(B) Intermittent. A requirement of service that demands operation for alternate intervals of (1) load and no load; or (2) load and rest; or (3) load, no load and rest.
(C) Periodic. A type of intermittent duty in which the load conditions are regularly recurrent.
(D) Short-Time. A requirement of service that demands operation at a substantially constant load for a short and definitely specified time.
(E) Varying. A requirement of service that demands operation at loads, and for intervals of time, both of which may be subject to wide variation.
(Title 24, Part 3, Article 100.)
Electric Line Truck. A truck used to transport workers, tools, and material, and to serve as a traveling workshop for electric power line construction and maintenance work. It is sometimes equipped with a boom and auxiliary equipment for setting poles, digging holes, and elevating material or workers.
Electric Supply Lines. Those conductors used to transmit electric energy and their necessary supporting or containing structures. Signal lines of more than 400 volts to ground are always supply lines within the meaning of the rules, and those of less than 400 volts to ground may be considered as supply lines, if so run and operated throughout.
Enclosed. Surrounded by a fence, wall, case, or housing which will prevent persons from accidentally contacting wiring, equipment, or energized parts contained therein.
(Title 24, Part 3, Article 100.)
Enclosure. 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.
(Title 24, Part 3, Article 100.)
Energized Parts (Live Parts). Parts which are of a potential different from that of the earth, or some conducting body which serves in place of the earth.
Environment. (See Atmosphere, also.)
(A) Damp Location. 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.
(B) Dry 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 some buildings under construction.
(C) Wet Location. Installations underground or in concrete slabs or masonry in direct contact with the earth, and locations subject to saturation with water or other liquids, such as vehicle washing areas, and locations exposed to weather and unprotected.
Equipment. A general term which includes fittings, devices, appliances, fixtures, apparatus, and the like, used as part of, or in connection with, an electrical power transmission and distribution system, or communication systems.
(Title 24, Part 3, Article 100.)
Explosion-Proof Apparatus. Apparatus enclosed in a case which is capable of withstanding an explosion of a specified gas or vapor which may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and which operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby.
(Title 24, Part 3, Article 100.)
Exposed (as applied to energized parts). Energized parts that can be inadvertently touched or approached nearer than a safe distance by a person. Parts not suitably guarded, isolated, or insulated.
(Title 24, Part 3, Article 100.)
Fault. (See Current.)
Feeder. Any conductors of a wiring system between the service equipment, or the generator switchboard of an isolated plant, and the branch circuit overcurrent device.
(Title 24, Part 3, Article 100.)
Fuse. An overcurrent protective device with a circuit opening fusible member directly heated and destroyed by the passage of overcurrent through it. (Note: A fuse comprises all the parts that form a unit capable of performing the prescribed functions. It may or may not be the complete device necessary to connect it into an electrical circuit.)
(A) Expulsion Fuse Unit (Expulsion Fuse). A vented fuse unit in which the expulsion effect of gases produced by the arc and lining of the fuseholder, either alone or aided by a spring, extinguishes the arc.
(B) Power Fuse Unit. A vented, non-vented, or controlled vented fuse unit in which the arc is extinguished by being drawn through solid material, granular material, or liquid, either alone or aided by a spring.
1. Vented Power Fuse. A fuse with provision for the escape of arc gases, liquids, or solid particles to the surrounding atmosphere during circuit interruption.
2. Non-Vented Power Fuse. A fuse without intentional provision for the escape of arc gases, liquids, or solid particles to the atmosphere during circuit interruption.
3. Controlled Vented Power Fuse. A fuse with provision for controlling discharge during circuit interruption such that no solid material may be exhausted into the surrounding atmosphere. The discharge gases shall not ignite or damage insulation in the path of the discharge, nor shall these gases propagate a flashover to or between grounded members or conduction members in the path of the discharge when the distance between the vent and such insulation or conduction members conforms to manufacturer's recommendations.
Ground. A conducting connection, whether intentional or accidental, between an electrical circuit or equipment and earth, or to some conducting body which serves in place of the earth.
(A) Ground (Reference). That conducting body, usually earth, to which electric potential is referenced.
(Title 24, Part 3, Article 100.)
Grounded Conductor. A system or circuit conductor which is intentionally grounded.
(Title 24, Part 3, Article 100.)
Grounded, Effectively. Permanently connected to earth through a ground connection of sufficiently low impedance and having sufficient ampacity that ground fault current which may occur cannot build up to voltages dangerous to personnel.
(Title 24, Part 3, Article 100.)
Grounded, Impedance. Connected to ground through a connection in which an impedance has been inserted intentionally.
(Title 24, Part 3, Article 3-100.)
Grounded, Solidly. Grounded through a grounding connection in which no impedance has been inserted intentionally.
(Title 24, Part 3, Article 3-100.)
Grounded System, Impedance. A system which has one conductor or point (usually the mid-tap or neutral point of a transformer or generator windings) connected to the reference ground through an impedance.
(Title 24, Part 3, Article 3-100.)
Grounded System, Solidly. A system which has one conductor or point (usually the mid-tap or neutral point of a transformer or generator windings) connected to the reference ground with no intentional impedance imposed in the circuit.
(Title 24, Part 3, Article 3-100.)
Grounding Conductor, Electrode. The conductor used to connect the grounding electrode to the equipment grounding conductor and/or to the grounded conductor of the circuit at the service, or at the source of a separately derived system.
(Title 24, Part 3, Article 100.)
Grounding Conductor, Equipment. The conductor used to connect noncurrent-carrying metal parts of equipment, raceways and other enclosures to the system grounded conductor at the service and/or the grounding electrode conductor or at the source of a separately derived system.
(Title 24, Part 3, Article 100.)
Grounding Connection (Ground Connection). (See Ground.)
(Title 24, Part 3, Article 100.)
Grounding Electrode (Ground Electrode). A conductor imbedded in the earth, used for maintaining ground potential on conductors connected to it, and for dissipating into the earth current conducted to it.
(Title 24, Part 3, Article 3-100.)
Grounding Conductor. A conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode.
(Title 24, Part 3, Article 100.)
Grounding Electrode Resistance. The resistance of the grounding electrode to earth.
Grounding Transformer. A transformer intended primarily for providing a neutral point for system grounding purposes.
(Title 24, Part 3, Article 3-100.)
Group Operation. The essentially simultaneous operation of all poles of a multi-pole switching device by one operating mechanism.
(Title 24, Part 3, Article 3-100.)
Guarded. Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers or casings, barriers, rails or screens, mats, or platforms intended to prevent or impede the approach of persons or objects to a point of danger.
(Title 24, Part 3, Article 3-100.)
High Voltage. A sustained voltage of more than 600 volts. (See Voltage.)
(Title 24, Part 3, Article 3-100.)
High-Voltage System. Associated electrical conductors and equipment operating at or intended to operate at a sustained voltage of more than 600 volts between conductors.
(Title 24, Part 3, Article 3-100.)
Hook Stick. (See Switch Stick.)
Hot Tools and Ropes. Tools and ropes which are especially designed for work on energized high voltage lines and equipment. Insulated aerial equipment especially designed for work on energized high voltage lines and equipment shall be considered hot line.
Indoor. Indoor, as an adjective, describes a device or equipment which, because of its construction, must be protected from the weather, or be installed in a location which is protected from the weather.
(Title 24, Part 3, Article 3-100.)
Induction Heating. The heating of a nominally conductive material due to its own I 2 R losses when the material is placed in a varying electromagnetic held.
Insulated. Separated from other conducting surfaces by a dielectric substance (including air space) offering a high resistance to the passage of current.
NOTE: When any object is said to be insulated, it is understood to be insulated in suitable manner for the conditions to which it is subjected. Otherwise, it is within the purpose of these orders, uninsulated. Insulating covering of conductors is one means of making the conductor insulated.
(Title 24, Part 3, Article 3-100.)
Insulation (As applied to Cable). That which is relied upon to insulate the conductor from other conductors or conducting parts or from ground.
(Title 24, Part 3, Article 3-100.)
Interlock. An electrical, mechanical, or key-locked device intended to prevent an undesired sequence of operations.
(Title 24, Part 3, Article 3-100.)
Interrupter Switch. (See Switching Devices.)
(Title 24, Part 3, Article 100.)
Interrupting Rating. (See Ratings.)
(Title 24, Part 3, Article 3-100.)
Isolated. Not readily accessible to persons unless special means of access are used.
Junction Box. (See Pull Box.)
(Title 24, Part 3, Article 3-100.)
Lanyard. A flexible line to secure a wearer of a safety belt or harness to a drop line, lifeline, or fixed anchorage.
Line Clearance Tree Trimming Operations. Operations which include the trimming, repairing, chemical treatment or removal of trees, brush and miscellaneous vegetation, performed in the vicinity of exposed energized overhead conductors and equipment.
Linemen's Body Belt. A leather or web (cotton or nylon) belt designed specifically for employees working on poles or structures. It consists of a waist belt, generally cushioned, with a front buckle, two D rings for attaching safety straps and a multiple-looped strap for holding rings, snaphooks, holsters and other tool holding devices.
Location. (See Environment.)
Magnetizing Current. (See Current--Excitation.)
Main Switch. (See Service Entrance Switch.)
(Title 24, Part 3, Article 3-100.)
Make and Latch (or Close and Hold) Rating. (See Ratings.)
(Title 24, Part 3, Article 3-100.)
Manhole. A chamber, in an underground system, containing working space large enough for a person o enter, which provides space and access for installation and maintenance of cables,transformers, or other equipment or apparatus.
(Title 24, Part 3, Article 3-100.)
Manhole Chimney. A vertical passageway for workers or equipment between the roof of the manhole and the surface (street) level.
(Title 24, Part 3, Article 3-100.)
Manual Control. (See Control.)
(Title 24, Part 3, Article 3-100.)
Manual Operation. (See Control.)
(Title 24, Part 3, Article 3-100.)
Maximum Voltage. (See Ratings.)
(Title 24, Part 3, Article 3-100.)
Metal-Clad Cable. A fabricated assembly of insulated conductor(s) in a flexible metallic enclosure.
(Title 24, Part 3, Article 3-100.)
Metal-Enclosed. Metal-enclosed, as an adjective, refers to electrical apparatus surrounded by a metal case or housing, usually grounded.
(Title 24, Part 3, Article 3-100.)
Minimum Bending Radius. The minimum recommended radius to which a conduit or an insulated cable may be bent, measured from its inner surface.
(Title 24, Part 3, Article 3-100.)
Minimum Operating Current. (See Current.)
Multiple Fuse. An assembly of two or more single-pole fuses.
Nominal System Voltage. (See Voltage.)
(Title 24, Part 3, Article 100.)
Nonpropagating Liquid. A liquid which, when subjected to a source of ignition, may burn but the flame will not spread from the source of ignition.
Oil (Filled) Cutout. (See Switching Devices.)
(Title 24, Part 3, Article 100.)
Open Wiring. Uninsulated conductors or insulated conductors without grounded metallic sheaths or shields installed above ground, but not inside apparatus or wiring enclosures.
(Title 24, Part 3, Article 3-100.)
Outdoor. Outdoor, as an adjective, describes a device or equipment of weatherproof construction, or a location exposed to the weather.
(Title 24, Part 3, Article 3-100.)
Overcurrent. (See Current.)
Overload. (See Current.)
Overtemperature Protective Device. (See Thermal Protector.)
(Title 24, Part 3, Article 3-100.)
Portable or Mobile Equipment. Electrical equipment mounted on skids, pads, legs, or vehicles, and capable of being moved to any required location.
Pothead. (See Cable Terminations.)
(Title 24, Part 3, Article 3-100.)
Power Fuse. (See Fuse.)
Protective Device. A device or combination of devices capable of detecting and automatically interrupting a specific condition.
(Title 24, Part 3, Article 3-100.)
Pull Box. A box with a blank cover into which workers may reach but not enter which is inserted in one or more runs of raceway to facilitate pulling, joining, supporting, or inspecting conductors. The term "pull box" includes but is not limited to: junction boxes, splice boxes, conductor support boxes, inspection boxes, and handholes.
(Title 24, Part 3, Article 3-100.)
Pulling Tension. The longitudinal force exerted on a cable during installation.
Qualified Electrical Worker. A qualified person who by reason of a minimum of two years of training and experience with high-voltage circuits and equipment and who has demonstrated by performance familiarity with the work to be performed and the hazards involved.
Qualified Line Clearance Tree Trimmer. A person who has completed a minimum of 18 months-related training and on-the-job experience and is familiar with the special techniques and hazards involved in line clearance tree trimming operations.
Qualified Line Clearance Tree Trimmer Trainee. Any worker regularly assigned to a line clearance tree trimming crew and undergoing on-the-job training who, in the course of such training, has demonstrated the ability to perform the assigned duties safely at that level of training.
Qualified Person. A person who by reason of experience or instruction is familiar with the operation to be performed and the hazards involved.
Raceway. Any channel for holding wires, cables or bus bars, which is designed expressly for, and used solely for, this purpose.
NOTE:
Raceways shall be permitted to be of metal or insulating material and the term includes rigid metal conduit, rigid nonmetallic conduit, flexible metal conduit, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface metal raceways, structural raceways, wireways and busways.
(Title 24, Part 3, Article 100.)
Rated. A designated value of an operating characteristic at which other characteristics are measured and specified.
(Title 24, Part 3, Article 3-100.)
Ratings.
(A) Basic Impulse Level (BIL). A reference impulse insulation strength expressed in terms of the crest value of the withstand voltage of a standard full impulse voltage wave.
(B) Interrupting Rating. Maximum interrupting capability under specified conditions, expressed in amperes or MVA.
(C) Make and Latch (Close and Hold) Rating. The highest RMS current at which the device or equipment is designed to operate.
(D) Short-Time Current Rating. The maximum RMS current a device, an assembly, or a bus is designed to carry for a specified short-time interval.
(Title 24, Part 3, Article 3-100.)
Readily Accessible. (See Accessible.)
(Title 24, Part 3, Article 100.)
Regulator Bypass Switch. (See Switching Devices.)
(Title 24, Part 3, Article 100.)
Release Free (Trip Free). A descriptive term indicating that the opening operation of a switching device can prevail over the closing operation during specified portions of the closing operation.
(Title 24, Part 3, Article 3-100.)
Riser (Cable Riser). A vertical run of insulate cable, associated raceway, and termination.
Safely Accessible. (See Accessible.)
Safety Strap. A web strap designed specifically for use in conjunction with a linemen's body belt to secure the employee to a pole or structure in a manner that permits work with both hands.
Service. The conductors and equipment for delivering energy from the electricity supply system to the wiring system of the premises served.
(Title 24, Part 3, Article 100.)
Service Conductors. That portion of the supply conductors which extends from the supply main, duct, or from transformers of the serving agency to the service equipment of the premises supplied. For overhead conductors this includes the conductors from the last line pole to the service equipment.
(Title 24, Part 3, Article 100.)
Service Entrance Conductors. The consumer-owned conductors extending between the service point and the service entrance equipment.
(Title 24, Part 3, Article 100.)
Service Entrance Switch (Main Switch). The disconnecting means and overcurrent protection installed at or near the service point.
(Title 24, Part 3, Article 100.)
Service Equipment. The necessary equipment, usually consisting of circuit breaker or switch and fuses, and their accessories, intended to constitute the main control and means of cutoff for the supply to a building or structure.
(Title 24, Part 3, Article 100.)
Service Factor. A multiplier which, applied to the rated output of an electric machine, indicates a permissible loading which may be carried continuously under the conditions for that service factor.
Service Point. The point of connection between the facilities of the serving agency and those of the consumer.
(Title 24, Part 3, Article 3-100.)
Shielded Cable. A cable in which the insulated conductor(s) is enclosed in a conducting envelope(s), so constructed that substantially every point on the surface of the insulation is at ground potential or at some predetermined potential with respect to ground.
Stored-Energy Operation. Operation by means of energy stored in the mechanism, sufficient to complete a specified operation.
Stress Cone. (See Cable Terminations.)
(Title 24, Part 3, Article 3-100.)
Submersible. Submersible, as an adjective, describes a device which is so constructed that it will operate satisfactorily when completely or partially submerged in a liquid under specified conditions.
Suitable. Capable of performing with safety the particular function specified in these Orders.
Supervised. Under continuous or intermittent surveillance by a local or remote operator or automatic data processing system.
Switch (Hook) Stick. A device with an insulated handle and a hook or other means for performing stick operation of a switching device.
Switching Device. A device designed to close and/or open an electric circuit.
(Title 24, Part 3, Article 100.)
Switching Devices.
(A) Circuit Breaker. A device designed to open and close a circuit by non-automatic means, and to open the circuit automatically on a predetermined overload of current, without injury to itself when properly applied within its rating.
(Title 24, Part 3, Article 100.)
(B) Cutout. An assembly of a fuse support with either a fuseholder, fuse carrier, or disconnecting blade. The fuseholder or fuse carrier may include a conducting element (fuse link), or may act as a disconnecting blade by the inclusion of a non-fusible member.
(Title 24, Part 3, Article 100.)
(C) Disconnecting Means. A device, or group of devices, or other means whereby the conductors of a circuit can be disconnected from their source of supply.
(Title 24, Part 3, Article 100.)
(D) Disconnecting (or Isolating) Switch (Disconnector, Isolator). A switch intended for isolating an electric circuit from the source of power. It has no interrupting rating and is intended to be operated only after the circuit has been opened by some other means.
(Title 24, Part 3, Article 3-100.)
(E) Interrupter Switch. A switch, capable of making, carrying, and interrupting specified currents.
(Title 24, Part 3, Article 100.)
(F) Oil Cutout (Oil-Filled Cutout). A cutout in which all or part of the fuse support and its fuse link or disconnecting blades are mounted in oil with complete immersion of the contacts and the fusible portion of the conducting element (fuse link), so that arc interruption by severing of the fuse link or by opening of the contacts will occur under oil.
(Title 24, Part 3, Article 100.)
(G) Oil Switch. A switch having contacts which operate under oil (or askarel or other suitable liquid).
(Title 24, Part 3, Article 100.)
(H) Regulator Bypass Switch. A specific device or combination of devices designed to bypass a regulator.
(Title 24, Part 3, Article 100.)
Tag. A system or method of identifying circuits, systems or equipment for the purpose of alerting persons that the circuit, system or equipment is being worked on.
Terminal Chamber. (See Cable Terminations.)
(Title 24, Part 3, Article 3-100.)
Test Position (of a switchgear assembly). That position in which the primary disconnecting devices of the removable element are separated by a safe distance from those in the housing and the secondary disconnecting devices are in operating contact.
(Title 24, Part 3, Article 3-100.)
Thermal Protector--General. An inherent protective device which is responsive to temperature or current, or both, and which, when properly applied, protects the equipment against overheating due to overload or failure to start.
(Title 24, Part 3, Article 3-100.)
Transformer Bank. A transformer installation consisting of two or more transformers.
Transformer Installation. An electrical installation consisting of one or more transformers, including associated lead wires and interconnections, which transforms electric energy from one or more alternating current circuits to one or more other alternating current circuits.
Transformer Primary Winding. The winding on the energy input (source) side.
Transformer Secondary Winding. The winding on the energy output (load) side.
Vault. A room (including manholes) of fire-resistant construction, primarily used to house electrical equipment.
(Title 24, Part 3, Article 3-100.)
Voltage.
(A) Maximum Voltage. (See Ratings.)
(Title 24, Part 3, Article 3-100.)
(B) Nominal System Voltage. A nominal value assigned to designate a system of a given voltage class.
(Title 24, Part 3, Article 3-100.)
(C) Voltage (of a circuit). The greatest root-mean-square (effective) difference of potential between any two conductors of the circuit concerned.
(Title 24, Part 3, Article 100.)
NOTE: On various systems such as 3-phase, 4-wire, single phase 3-wire and 3-wire direct current, there may be various circuits of various voltages.
(Title 24, Part 3, Article 100.)
(D) Voltage to Ground. In grounded circuits the voltage between the given conductor and that point or conductor of the circuit which is grounded; in ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit.
(Title 24, Part 3, Article 100.)
Weatherproof. So constructed or protected that exposure to the weather will not interfere with successful operation.
(Title 24, Part 3, Article 100.)
NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code; and Section 18943(c), Health and Safety Code.
HISTORY
1. New Group 2 (Articles 50 through 86, Sections 2700 through 2949) filed 7-27-73; effective thirtieth day thereafter (Register 73, No. 30). Approved by State Building Standards Commission 2-23-73.
2. Amendment and deletion of numbers preceding definitions of subsection (b) filed 10-14-75 as an emergency; effective upon filing (Register 75, No. 42). Issuing Agency: Occupational Safety and Health Standards Board.
3. Certificate of Compliance filed 1-9-76 (Register 76, No. 2).
4. Amendment of subsection (b) filed 7-6-79 as procedural and organizational; effective upon filing (Register 79, No. 27).
5. Amendment of subsection (b) filed 8-9-79; effective thirtieth day thereafter (Register 79, No. 32).
6. Amendment of subsection (b) filed 10-29-80; effective thirtieth day thereafter (Register 80, No. 44).
7. Amendment filed 2-1-83; effective thirtieth day thereafter (Register 83, No. 6).
8. Editorial correction including renumbering of former Article 50 to Article 1 filed 11-2-83 (Register 83, No. 45).
9. Amendment filed 12-10-87; operative 1-9-88 (Register 88, No. 1).
Go Back to Article 1 Table of Contents
| The above information is provided free of charge by the Department of Industrial Relations from its web site at www.dir.ca.gov. |