电气英语证书考试(PEC)-电气自动化专用术语.doc

电气英语证书考试(PEC)-Glossary of Electrical Engineering and Automation

100BaseT - A synonym for the Fast Ethernet network standard. The "100" refers to a maximum data-transfer rate of 100 megabits per second over twisted pair, copper wire.

10BaseT - A synonym for the Fast Ethernet network standard. The "10" refers to a maximum data-transfer rate of 10 megabits per second over twisted pair, copper wire.

10K - A grade level Box or Cover rating. See "Incidental Light Traffic".

1A - 1 Normally Open

1B - 1 Normally Closed

20A - A California ruling that has the investor owned utilities performing the under-grounding of electrical cables. The funds to perform the work are derived from rates and go into a sinking fund that is used at the discretion of the municipality the electric

20B - A California ruling that has the investor owned utilities performing the under-grounding of electric cables. The funds to perform this work are derived from a combination of rates and the developer of the land the line is on. This work is done at the di

20C - A California ruling that has the investor owned utilities performing the under-grounding of overhead electrical cables. The funds to perform this work are derived from the developer of the land the line is on.

20K - A grade level Box or Cover rating. See "Occasional Traffic".

2S1W - Two Speed, 1 Winding (motor).

2S2W - Two Speed, 2 Winding (motor).

3 Phase - See "Three Phase" and "Polyphase"

600 Volt - Electrical systems, cables or service designed to be operated under 1000 Volts.

600V-UD - 600 Volt Underground Distribution Cable.

802.11a - A specification for a wireless LAN that operates in the 5GHz frequency range and provides a data transmission rate of 54Mbps using spread spectrum technology.

802.11b - A specification for a wireless LAN that operates in the 2.4GHz range and provides a data transmission rate of 11Mbps using spread spectrum technology. This specification was known as Wi-Fi but the term now applies to 802a and 802g as well.

802.11g - A specification for a wireless LAN that operates in the 2.4GHz frequency range and provides a data transmission rate, over short distances, of 54Mbps using orthogonal frequency division multiplexing (OFDM) technology.

802.1x - A security standard for wired and wireless LANs.

A

A - 1) Amperes; Amps. 2) Area. For cables Area is expressed in Circular Mils.

A-H - Ampere-Hour

A/D Conversion - The process of converting an analogue signal into an equivalent digital one utilizing an A/D converter.

AA - 1) The Aluminum Association. 2) Refers to All Aluminum as in All Aluminum Conductor.

AAAC - All Aluminum Alloy Conductor

AAC - All Aluminum Conductor.

AAC/TW - All Aluminum Conductor, Trapezoidal-Shaped Aluminum Strands.

AASHTO - American Association of Safety Highway Traffic Officials

Absorbed Glass Mat - Absorbed Glass Mat, also known as AGM, is a newer type of battery construction that uses saturated absorbent glass mats rather than gelled or liquid electrolyte. It is somewhat more expensive than flooded (liquid) type, but offers good reliability and fa

AC - See "Alternating Current"

ACAR - All Aluminum Conductor, Aluminum Alloy Reinforced.

ACB - Air Circuit Breaker

Access Point - A wireless networked device usually connected to a wireless LAN used to access the wired LAN.

Accuracy - The degree of uncertainty for which a measured value agrees the ideal value.

Accuracy Class - A number used to indicate the accuracy range of a measurement transducer, according to the defined standard.

ACSR - Aluminum Conductor Steel Reinforced.

ACSR/AW - Aluminum Conductor, Aluminum Clad Steel Reinforced.

ACSR/TW - ACSR conductor made using Trapezoidal Wire construction.

ACSS - Aluminum Conductor Steel Supported. This is a conductor that is generally used for overhead transmission construction. ACSS is often preferred over ACSR because of its superior sag characteristics.

ACSS/AW - Aluminum Conductor, Aluminum Clad Steel Supported.

ACSS/TW - ACSS conductor made using Trapezoidal Wire construction.

Active Material (Battery) - Material which reacts chemically to produce electrical energy when the cell discharges. The material returns to its original state during the charging process.

Active Power - A term used for power when it is necessary to distinguish among Apparent Power, Complex Power and its components, and Active and Reactive Power.

Adjustment - The operation intended to bring a transducer into a state of performance suitable for its use.

Admittance - The reciprocal of Impedance (1/Z).

ADSL - Asymmetric Digital Subscriber Line. ADSL uses standard phone lines to provide high speed data communications. ADSL upstream speeds (from the user) normally top out at 128Kbps and downstream (to the user) at no more than 1.5Mbps. A separate phone line i

AEIC - Association of Edison Illuminating Companies. 
[www.aeic.org]

Aeolian Vibration - A natural forced vibration caused by wind flowing over a conductor. This occurs at alternate wind induced vortices and at wind speeds typically at 8 to 12 MPH. Contact Young & Company for additional information including the formula to calculate Aeolian

Aerial Cable - An assembly of insulated conductors installed on a pole or similar overhead structures. It may be self supporting or attached to a messenger cable.

AFCI - Arc Fault Circuit Interrupter

AFD - Adjustable Frequency Drive

AFI - Arc Fault Interrupter

AGM - See "Absorbed Glass Mat"

AIC - Arc Interrupting Current

Air Blast Breakers - A variety of high voltage circuit breakers that use a blast of compressed air to blow-out the arc when the contacts open. Normally, such breakers only were built for transmission class circuit breakers.

AIS - Air Insulated Switchgear

Al - The chemical symbol for aluminum.

Alarm - A signal for attracting attention to some abnormal event.

ALJ - Administrative Law Judge

All-or-Nothing Relay - An electrical relay which is intended to be energized by a quantity, whose value is either higher than that at which it picks up or lower than that at which it drops out.

Alley Arm - A side brace for a cross arm that is not loaded (balanced) evenly.

Alley Roadway (Lighting) - Narrow public ways within a block, generally used for vehicular access to the rear of abutting properties.

Alligator - A specialized tool attached to a hot stick used to tie a wire or cable into an insulator.

Alloy - A metal formed by the combination of two or more metals.

Alternating Current - An electric current that reverses direction at regular intervals, having a magnitude that varies continuously in a sinusoidal manner.

Ambient Temperature - The temperature surrounding an object.

American Wire Gage (AWG) - A standard system used in the United States for designating the size of an electrical conductor based on a geometric progression between two conductor sizes.

AMF (Lighting) - Average Maintained Foot-candles

Amorphous Semiconductor - A non-crystalline semiconductor material used in photovoltaic panel construction. It is easier and less costly to manufacture than crystalline, but is less efficient and degrades over time. It is also known as thin film.

Ampacity - The current in amperes that a conductor can carry continuously under given conditions of use without exceeding its temperature rating.

Ampere - The unit expressing the rate of flow of an electric current. One ampere is the current produced by a difference in potential of one volt across a resistance of one ohm; An electric current flowing at the rate of one coulomb per second.

Ampere-Hour - The use of one Ampere for one hour.

Ampere-hour capacity (storage battery) - The number of ampere-hours that can be delivered under specified conditions of temperature, rate of discharge, and final voltage.

Ampere-hour meter - An electric meter that measures and registers the integral, with respect to time, of the current of a circuit in which it is connected.

Anchor - A device that supports and holds in place conductors when they are terminated at a pole or structure. The anchor is buried and attached to the pole by way of guy wire to counteract the mechanical forces of these conductors.

Anneal - The process of controlled heating and cooling of a metal. In wire and cable products, copper and aluminum are annealed to increase flexibility while maintaining adequate strength.

Anode - 1) The positive electrode that emits positive ions and attracts negative ions, within a voltaic cell or other such device. 2) The positive pole of a battery.

ANSI - American National Standards Institute. ANSI is located at 1430 Broadway, New York, NY 10018.

Antenna Gain - An antenna's transmission power, provided as a ratio of its output (send) signal strength to its input (receive) signal strength, normally expressed in dBi. The higher the dBi, the stronger the antenna.

Anti-Pumping Device - A feature incorporated in a Circuit Breaker or re-closing scheme to prevent repeated operation where the closing impulse lasts longer than the sum of the relay and CB operating times.

Apparent Power (volt-amps) - The product of the applied voltage and current in an ac circuit. Apparent power, or volt-amps, is not the true power of the circuit because the power factor is not considered in the calculation.

AR - Automatic Recloser.

Arc - A discharge of electricity through air or a gas.

Arc Flash - An arcing fault is the flow of current through the air between phase conductors or phase and neutral or ground. An arcing fault can release tremendous amounts of concentrated radiant energy at the point of the arcing in a small fraction of a second result

Arc Thermal Performance Value - Maximum capability for arc flash protection of a particular garment or fabric measured in calories per square centimeter. Though both garments and fabrics can be used for protection a garment made from more than one layer of arc flash rated fabric will ha

Arcing Time - The time between instant of separation of the CB contacts and the instant of arc excitation.

Armor - An outer metal layer applied to a cable for mechanical protection. Armor is comprised of factory formed wire, designed to be applied to a range of conductor sizes. Preformed Line Products manufacturers Armor.

Armor Rod - An outer metal layer applied to a cable for mechanical protection. Armor Rods are comprised of factory formed wire, designed to be applied to a range of conductor sizes. Preformed Line Products manufacturers Armor Rods.

Array - For photovoltaic systems, a number of photovoltaic modules connected together to provide a single electrical output. Also see "Photovoltaic Array".

Arrester - Short for Surge Arrester, a device that limits surge voltage by diverting it.

Askeral - A generic term for a group of synthetic, fire-resistant, chlorinated aromatic hydrocarbons used as electrical insulated fluids.

ASTM - American Society for Testing and Materials. ASTM is located at 1916 Race Street, Philadelphia, PA 19103.

ATC - Available Transfer Capacity

ATP - Alternative Transient Program

Automatic line sectionalizer - A self-contained circuit-opening device that automatically opens the main electrical circuit after sensing and responding to a predetermined number of successive main current impulses.

Automatic Recloser - An automatic switch used to open then reclose following an over current event on a distribution voltage (medium voltage) line.

Autonomous Photovoltaic System - A stand-alone Photovoltaic system that has no back-up generating source. The system may or may not include storage batteries. Most battery systems are designed for a certain minimum number of days or operation before recharging is needed should sufficie

Autotransformer - A transformer in which at least two windings have a common section. They are use to either "buck" or "boost" the incoming line voltage.

Auxiliary Power - The power required for correct operation of an electrical or electronic device, supplied via an external auxiliary power source rather than the line being measured.

Auxiliary Relay - An all-or-nothing relay energized via another relay. An example is a measuring relay, for the purpose of providing higher rated contacts, or introducing a time delay, or providing multiple outputs from a single input.

Average Maintained Foot-candles (Lighting) - (ILL x CU x LLF)/(PS x RW)

AWG - American Wire Gauge.

Azimuth - The angle between true north and the projection of a surface normal to the horizontal plane, measured clockwise from the north. As applied to a Photovoltaic array, 180 degrees azimuth means the array faces south.

B

Baker Board - A insulated platform used to work above the ground on a pole.

Balanced Load - Refers to an equal loading on each of the three phases of a three phase system...

Balanced polyphase system - A polyphase system in which both the currents and voltages are symmetrical.

Ballast - A device that by means of inductance, capacitance, or resistance, singly or in combination, limits the lamp current of a fluorescent or high intensity discharge lamp. It provides the necessary circuit conditions (voltage, current and wave form) for start

Bandwidth - The data carrying capacity of a transmission path, measured in bits or bytes per second.

Bank - A group of electrical devices, usually transformers or capacitors, connected in a way to increase capacity or to inter connect as three-phase.

Basic impulse level (BIL) - A reference impulse (voltage) insulation strength expressed in terms of the peak value of the withstand voltage of a standard impulse voltage wave. It is used to express the ability of electrical equipment such as transformers to withstand certain levels

Basic Insulation Level - A design voltage level for electrical apparatus that refers to a short duration (1.2 x 50 microsecond) crest voltage and is used to measure the ability of an insulation system to withstand high surge voltage.

Battery - A combination of two or more chemical cells connected together electronically to produce electrical energy.

Battery Tray - A contained with a base and walls for holding several cells or batteries.

Bay-O-Net - A fusing device frequently used to protect transformers and downstream devices. A Bay-O-Net fuse may include a Partial Range Current Limiting Fuse in series with n under oil fuse link.

Beacon - In wireless networking, a beacon is a packet sent by a connected device to inform other devices of its presence and readiness.

Beam Spread - With regard to outdoor light, the angle between the two directions in a plane in which the intensity is equal to a stated percentage of the maximum beam intensity. The percentage is typically 10% for floodlights and 50% for roadway luminaries.

Belt - Refers to