arrester dictionary.doc

Arrester DictionaryAacceptance tests arrester arrester agingarrester body, EGLA SVU arrester classification arrester - deadfront typearrester - dead-break arrester discharge current arrester discharge voltage arrester disconnector arrester - dist, heavy duty arrester - dist, light duty arrester - dist, normal duty arrester duty cycle rating arrester - EGLA arrester - GIS-arrester arrester - high voltage arrester - line discharge class arrester - liquid-immersed type arrester - load-break arrester arrester - medium voltage arrester - MOV type arrester - polymer-housed arrester - riser pole type arrester - separable typearrester - station class arrester unit arrester - 5kA arrester arrester - 10kA arrester average sparkover voltage BBILBSL backflashback flashover rate, BFOR bending moment breaking load Ccertification tests CFO classifying current composite hollow core insulator conditioning testsconformance tests continuous current of arrester continuous operating voltage - Uc conventional BIL conventional BSL coefficient of grounding (COG) conventional withstand voltage coordination of insulation cracking creepage distance crest value critical flashover voltage (CFO) Ddamage limit deadfront type arrester deflector degradation design tests designation of an impulse shape disconnectordischarge counter discharge current discharge indicator discharge voltage discharge voltage-current characteristic discharge withstand current disruptive discharge distribution arrester duty-cycle voltage rating Eearth fault factor electrical unit electrical agingelectrical unit of SVU energy absorption capability externally gapped line arresters, EGLA Ffail-open current rating for liquid-immersed arrester fail-short current rating for liquid-immersed arrester fast-front overvoltage, FFO fault indicator ferroresonance flashover flashover rate, FOR follow current (i-follow) follow current of an arrester front of an impulse front-of-wave impulse sparkover voltage Ggapless grading current grading or control ring ground lead disconnectorground terminal Hhigh current impulse highest system voltage, Us highest equipment voltage Um housing hydrophobic hydrophilic IIEC IEEEimpulse impulse protective level - IEC impulse protective level - IEEEimpulse protective volt-time characteristic impulse sparkover voltage impulse sparkover volt-time characteristic impulse withstand voltage indoor arrester insulation coordination insulation level internal grading system of an arrester ionization current ionization voltage Llead lengthlightning lightning current impulse lightning impulse protective level, LIPL lightning impulse withstand voltage, LIWV lightning overvoltage lightning surge line arrester line discharge class line terminal liquid-immersed type arrester long-duration current impulse Mmargin of protectionmaximum continuous operating voltage rating (MCOV) maximum design cantilever load-static (MDCL-static) maximum system voltage mean breaking load, MBL mechanical unit metal-oxide surge arrester (MOSA) metal-oxide surge arrester without gaps metal-oxide surge arrester with gapped structures metal-oxide surge arrester with external series gap (EGLA) metal-oxide varistor (MOV) MOSA MOV arrester Nneutral earthing or grounding nominal discharge currentnominal rate of rise nominal system voltage non-gapped line arresters, NGLAnon-linear metal-oxide resistor nonself-restoring insulation normal lightning current Oovervoltage operating duty cycle oscillatory surge outdoor arrester Ppartial discharge (PD) peak value peak (crest) value of opposite polarity of an impulse polymer-housed arrester porcelain-housed arrester power-frequency sparkover voltage power-frequency withstand voltage power-frequency withstand voltage versus time characteristic pressure-relief device of an arrester pressure relief rating production tests prorated section prospective (available) short-circuit current (at a given point in a circuit) protective characteristics of an arrester protective zone puncture Rradio-influence voltage (RIV) rating rated frequency of an arrester rated voltage of an arrester Ur reference current (Iref) reference current of an SVU (Iref) reference voltage (Vref) (Uref) reference voltage of an SVU (Uref) residual voltage of an arrester, Ures riser pole type arrester routine tests S salt deposit density (SDD) section of an arrester self-restoring insulation separation distanceseries gap severe lightning current shed shielding failure flashover rate, SFFOR shielding failure rate, SFR shunt gap single energy absorption capability slow-front overvoltage, SFO sparkover SPD specified continuous load (SCL) specified short-term load (SSL) standard lightning impulse standard lightning impulse sparkover voltage standard switching impulses statistical (BIL) statistical (BSL) statistical withstand voltage steep current impulse strike distance surface current of SVU surge surge arrester switching impulse protective level (SIPL) switching overvoltage switching surge switching current impulseswitching impulse withstand voltage, SIWV switching surge flashover rate, SSFOR system voltage system neutral grounding system grounding Ttail of an impulse terminals terminal line forcetime-to-impulse sparkover tracking temporary overvoltage (TOV)thermal energy absorption capability thermal runaway of an arrester thermal stability of an arrester time to sparkover torsional loading TOV curvetransient overvoltage transmission line arrestertraveling wavetype tests (design tests) Uultimate mechanical strength-static (UMS-static) unit operation unit of an arrester Vvalve arrester valve element vent verification test for EGLA & insulator coordination very-fast-front overvoltage, VFFO vibration withstand test virtual duration of wave front virtual zero point virtual steepness of impulse virtual time to half-crest on the tail T2 virtual duration of a rectangular impulse Wwave wave front waveshape waveshape designation wave tail withstand voltage acceptance tests IECtests made on arresters or representative samples after agreement between manufacturer and purchaser arrester IEC and IEEEA protective device for limiting surge voltages on equipment by discharging or bypassing surge current around the protected device, without any power frequency current flowing to ground, and is capable of repeating these functions as repeatedly. Sometimes spelled arrestor. Related terms: Surge arrester, SPD arrester agingThere are two types of aging that can occur in arresters. Both are forms of long term degradation.Disk Aging: This is a slow change in the electrical characteristic of the ZnO varistor due to electrical stress over time. If this does occur, the losss of the disk and arrester may increase to a point where the arrester could fail due to excess heating and thermal runaway of the disks. Shed Aging: This is a slow change in the physical characteristics of the weather sheds that can lead to external flashover or puncture. If puncture occurs the arrester may fail internally due to ingress of moisture of contamination. arrester body, EGLA SVU IECnon-linear metal oxide resistor part, contained in a housing, which must be connected with an external series gap to construct a complete EGLA; the arrester body may include several units. arrester classification IEC and IEEEArrester classification or arrester class is determined by prescribed test requirements of a standard. For arresters classified per IEEE standards, the classifications are station, intermediate, distribution heavy duty, distribution normal duty, distribution light duty. arrester- deadfront type, dead-front arrester IEEEAn arrester assembled in a shielded housing providing system insulation and conductive ground shield, intended to be installed in an enclosure for the protection of underground and pad-mounted distribution equipment and circuits. arrester - dead-break IECarrester which can be connected and disconnected from the circuit only when the circuit is de-energized. arrester discharge current IEC and IEEEThe current that flows through an arrester resulting from an impinging surge. arrester discharge voltage IEC and IEEEThe voltage that appears across the terminals of an arrester during the passage of discharge current. arrester disconnector IEC and IEEEA device that provides a means for disconnecting an arrester in anticipation of, or after, a overloaded in order to prevent a permanent fault on the circuit and to give indication of an overloaded arrester.NOTEClearing of the fault current through the arrester during disconnection is generally done by the nearest source side overcurrent-protective device. arrester - distribution, heavy duty class: IEEEAn arrester normally used to protect overhead distribution systems exposed to severe lightning currents. Related term: IEC Class 1 arrester arrester - distribution, light duty class IEEEAn arrester normally installed on and used to protect underground distribution systems where the major portion of the lightning stroke current is discharged by an arrester located at the overhead line/cable junction. arrester - distribution, normal duty class IEEE An arrester normally used to protect overhead distribution systems exposed to normal lightning currents. arrester duty cycle rating IEEEThe designated maximum permissible root-mean-square (rms) value of power-frequency voltage between its line and ground terminals at which it is designed to perform its duty cycle rating. arrester EGLA IECAn externally gapped line arrester. The body of the arrester is referred to the SVU arrester - gas-insulated metal enclosed surge arrester, GIS-arrester IECgas-insulated metal-enclosed metal-oxide surge arrester without any integrated series or parallel spark gaps, filled with gas other than air and used in gas-insulated switchgears.NOTE The gas pressure is normally higher than 1 bar = 105 Pa.= 14.7psi arrester high voltage IECan arrester applied to transmission lines and generally tested to IEC standards. Related terms: station arrester, intermediate arrester, line discharge class 2.3.4.5 arresters. arrester- line discharge class 2,3,4,5 IECArresters tested per IEC 60099-4 and meet the test requirements of line discharge class 2,3,4,5 arresters arrester - liquid-immersed type IEC and IEEEAn arrester designed for use immersed in an insulating liquid. Also referred to as under-oil arrester. arrester - load-break arrester IECarrester which can be connected and disconnected when the circuit is energized. arrester medium voltage IECan arrester applied to distribution circuits and generally tested to IEC standards. Related terms; distribution arrester arrester - MOV type IEC and IEEEan arrester fabricated using nonlinear metal-oxide varistors for the valve elements. arrester - polymer-housed IEC and IEEEarrester using polymeric and composite materials for housing, with fittings.NOTE Designs with an enclosed gas volume are possible. Sealing may be accomplished by use of the polymeric material itself or by a separate sealing system. arrester - riser pole type IEEEAn arrester for pole mounting normally used to protect underground distribution cable and equipment. arrester - separable type, separable arrester IECarrester assembled in an insulated or screened housing providing system insulation, intendedto be installed in an enclosure for the protection of distribution equipment and systems.Electrical connection may be made by sliding contact or by bolted devices; however, allseparable arresters are dead-break arresters.NOTE The use of separable arresters is common in Europe.NOTE 1 Most dead-front arresters are load-break arresters.NOTE 2 The use of dead-front arresters is common in the USA. arrester - station class IEEEAn arrester tested per IEEE C62.11 that meets all station class test requirements. This arrester is generally of higher energy capability and better discharge characteristics than distribution and intermediate class arresters. arrester unit IEC and IEEEAny section of a multi-unit arrester. arrester 5kA arrester IEC and IEEEAn arrester that has a nominal discharge current o