High Voltage Terminology
American National Standards Institute (ANSI)- An organization that identifies industrial and public requirements for national census standards and coordinates and manages their development, resolves national standards problems, and ensures effective participation in international standardization. ANSI does not itself develop standards. Rather, it facilitates development by establishing consensus among qualified groups. ANSI ensures that the guiding principles- consensus, due process, and openness- are followed.
Ampacity - The current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Ampere - The measurement of intensity of rate of flow of electrons in an electric circuit. An ampere is the amount of current that will flow through a resistance of one ohm under a pressure of one volt.
Arc Fault Circuit Interrupter (AFCI)- A device intended to provide protection from the effects of arc faults by recognizing characteristics unique to arcing and functioning to de-energize a circuit when an arcing fault is detected.
Ballast- Used for energizing fluorescent lamps. It is constructed of a laminated core and coil windings or solid state electronic components.
Bonding - The permanent joining of metallic parts to form an electrically conductive path that will ensure electrical continuity and the capacity to conduct safely any current likely to be imposed.
Branch Circuit- The current conductors between the final over current device protecting the circuit and outlets.
Circuit Breaker- A device designed to open and close a circuit by no automatic means and to open the circuit automatically on a predetermined over current without damage to itself when properly applied within its rating.
Bare - A conductor having no covering or electrical insulation whatsoever.
Covered - A conductor encased within material composition or thickness that is not recognized by this code as electrical insulation.
Insulated - A conductor encased with material of a composition and thickness that is recognized by this code as electrical insulation.
Current- The flow of electrons through an electrical circuit, measured in amperes.
Disconnecting Means - A device or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply.
Fuse - An over current protective device with a fusible link that operates to open the current on an over current device.
Ground - A conductive connection, whether intentional or accidental, between an electrical circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounded - Connected to earth or to some conducting body that serves in place of the earth.
Ground Fault Circuit Interrupter (GFCI)- 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.
Equipment - Recognizable as suitable for the specific purpose, function, use, environment, application, and so on, where described in a particular code requirement.
Terminal - The identification of terminals to which a grounded conductor is to be connected shall be substantially white in color. The identification of other terminals shall be of a readily distinguishable different color.
National Fire Protection Association (NFPA)- Located in Quincy, MA. The NFPA in an international Standards Making Organization dedicated to the protection of people from the ravages of fire and electric shock. The NFPA is responsible for developing and writing the National Electrical Code, The Sprinkler Code, The Life Safety Code, The National Fire Alarm Code, and over 295 other codes, standards, and recommended practices. The NFPA may be contacted at (800)344-3555 or on their website at www.nfpa.org .
Neutral - In residential wiring, the neutral conductor is the grounded conductor in a circuit consisting of three or more conductors. There is no neutral in a two-wire circuit, although electricians refer to the white grounded conductor as the neutral.
Occupational Safety and Health Act (OSHA)- This the code of federal regulations developed by the Occupational Safety and Health Administration, U.S. Department of Labor. The electrical regulations are covered in part 1910, Subpart S. In order to shorten and simplify regulations, Part 1910, and Subpart S contains only the most common performance requirements of the NEC. The NEC must still be referred to in conjunction with OSHA regulations.
Ohm - A unit of measure for electric resistance. An Ohm is the amount of resistance that will allow one ampere to flow under a pressure of one volt.
Service Drop - 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 Equipment – The necessary equipment, usually consisting of a circuit breaker or switch and fuses, and their accessories, located near the point of entrance of supply conductors of a building, or other structure, or otherwise defined area, and intended to constitute the main controls and means of cutoff of the supply.
Service Lateral - 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 with adequate space, inside or outside the building wall. Where there is no terminal box, meter, or other enclosure with adequate space, the point of connection shall be considered to be the point of entrance of the service conductors into the building.
Service Point - The point of connection between the facilities of the serving utility and the premises wiring.
Short Circuit - A connection between any two or more conductors of an electrical system in such a way as to significantly reduce the impedance of the circuit. The current flow is outside of its intended path, thus the term “short circuit”. A short circuit is also known as a fault.
UL - Underwriters Laboratories Inc. is a independent, not-for-profit product safety certification organization that has been testing products and writing standards for safety for over a century. UL evaluates more than 19 thousand types of products, components, materials, and systems per year. Universally recognized and accepted, regulatory authorities rely upon the UL Mark for safety. www.ul.com
UL Mark - The UL Mark on a product means that UL has tested and evaluated representative samples of that product and determined that they meet UL's requirements. Under a variety of
programs, products are periodically checked by UL at the manufacturing facility to make sure they continue to meet UL requirements.
Volt- The difference between electric potential between two points of the conductor carrying a constant current of one ampere, when the power dissipated between these points is equal to one watt. A voltage of one volt can push one ampere through a resistance of one Ohm.
Watt- A measure of true power. A watt is the power to do the work at the rate of one joule per second. Wattage is determined by multiplying voltage times amperes times the power factor of the circuit.
Water Tight - Constructed so the the water will not enter the enclosure under specified tests with successful operation.
Water Proof - Constructed or protected so that exposure to the weather will not interfere with successful operation. Rainproof, rain tight, or water tight equipment can fulfill the requirements for weather proof where varying weather conditions other than wetness, such as snow, ice, dust, or temperature extremes, are not a factor.
Low Voltage Terminology
Bandwidth - The difference between the upper and lower limits of a given band of frequencies.
Broadband - The technique used to multiplex networks on a single cable without interfacing with each other.
Category Cable - Cables that comply with TIA/EIA-568-A. The higher the category number, i.e. Cat5; the better the cable's electrical performance to carry high speed signals. All cables are 100ohms.
Category 3 (cat 3)- Transmission characteristics up to 16MHZ.
Category 4 (cat 4)- Transmission characteristics up to 20MHZ.
Category 5 (cat 5)- Transmission characteristics up to 100MHZ.
Category 5e (cat 5e)-Transmission characteristics up to 100MHZ.
Category 6 (cat 6)-This standard is currently in draft. The proposed transmission characteristics will be around 250MHZ.
Coaxial Cabling - A transmission medium noted for its high bandwidth and low susceptibility to interference. Most commonly used for transmission of video signals. It has a coaxial cross section, where the center core is the signal conductor, while the outer shield protects it from external electromagnetic interference.
Cross Talk - The interface caused by a signal traveling over one cable pair on a signal traveling on an adjacent cable pair.
Daisy Chain - The connection of multiple devices in a serial fashion.
Fiber Optics - A technology that uses light for transmission data. Transmission characteristics are around 10GB/s. Currently 40GB/s testing is underway.
Home Run - A cabling method in which each cable is run directly to the work station outlet (star wiring)
Hub - A device used for the convergence of data from one or more locations and forwards the data out to one or more locations.
Multimode Fiber - A fiber that propagates more than one mode of light transmission. Commonly used with LED sources of low speed, short distance links.
NEC - Abbreviation for National Electric Code. Electrical contractors are required to follow the NEC standards and practices for installing copper wiring systems, low voltage, and fiber optic cabling.
Network - A system of cables, hardware, and equipment used for communications.
Patch Cord - Cable utilized to connect telecommunications circuits or links at the cross connect.
RG-6 Quad Shield Coax - Handles television ( antenna or cable), satellite dish, cable modem, or audiovisual modular signals. (An audiovisual modulator creates new TV channels for front door cameras, DVD player, and a VCR or satellite receiver.)
Router - A device used for the forwarding of data from networks (LANS) using the OSI network layer or the IP layer.
Star Wiring - A method of cabling each telecommunication outlet directly to cross connect/hub.
Single Mode Fiber - A fiber that uses only one mode of light transmission. Commonly used with laser sources for high speed, long distance links.
TIA/EIA - Abbreviation for Telecommunications Industry Association/Electronic Industries Association. The TIA/EIA sets the standards for the cabling industry.
UTP - Abbreviation for Unshielded Twisted Pair. A cable that consists of two or more unshielded insulated pairs that are twisted around each other to reduce induction. More commonly referred to as category cable.