Metal Oxide Surge Arrester for Generator and Electromotor Protection
Usys---Nominal system voltage
Umcov---Continuous operating voltage
Urat---Rated voltage of MOA
Ures--Residual voltage of MOA
U1mA---Reference voltage at 1mA d.c. Current
Uref---a.c. Reference voltage atresistive currnt1mA
12ms2ms---2ms rectangular current withstand
Uimp.spv---Impulse sparkover voltage
Uacsp---Power frequency discharge voltage
Hbas---Insulating base height
Dmax---Maximum shell diameter
Lspec---Specific creepage path
MOA for Generator and Electromotor Protection
Technical parameters of MOA for generator and electomotor protection
Type of MOA
Three phases combined MOA
Theer-phases-in-one combination polymeric housed MOA is designed for protecting 35kv(or lower) neutral-point non-earthing electrical equipments form damage due to over-voltage.Because of the special structure and excellent V-I characteristic of ZnO varistor,its protective performance,reliability and service life are improved.Many actual operations prove that,besides limiting lightning over-voltage,it also can limit over-voltages between phase to phase and phase to ground by switch-on or switch-off of vacuum swithch. Thus protecting electrical equipments Insulation and vacuum switch from flashover between phases and phase to ground. Because of its excellent protection capabilities,one set of three-phase combined MOA can replace six sets of ordinary MOAs.
Metal Oxide Surge Arrester(MOA) without Gaps for A.C.Sytems
MOA is composed of metal oxide varistors,housing(porcelain or silicon rubber),base,upper cover,grading ring etc.Our products have excellent performance in accordance with IEC international standard IEC600 99-4(2000) and China National Standard GB11032-2000 for "Alternating Current Gapless MOA".Polymeric housed MOA manufactured by AMTECH features small size,lightweight,simple manufacturing process,good sealing,explosion-proof,long working life,wounded-proof,high pollution resistance and reduced line maintenance,etc.
MOA Classification Code
Gapless arrester electrical parameter
|Type||Rated voltage||MCOV||Residual voltge(kv)|| |
Wave impluse withstand current
2000µ S square
4/10µ S high
|Steep impluse current||Switching impluse current|| |
8/20 µ Lightning impluse current
Zinc-oxide lightning arrester is the most advanced Over-Voltage Protector at present in the world. The voltage current characteristic of the varistor has been changed compared with traditional carborundum arresters due to the multiple metal oxide materials application in the core element-varistor,which has greatly improved the varistor's throughput capacity and brought thorough change to arresters'characteristics.
When arrester is under normal voltage,there is only microamp current through it .When it is under high voltage,arresters'excellent nonlinear voltage current feature gets into play,so the current through arresters will reach thousands of amperes and the arresters are at conducting status,releasing over-voltage energv to effectively protect the power transmission equipments from damage caused by over voltage.
Application and features
Zinc-oxide lightning arrester is protective equipment for electrical devices in A.C.power system from damage caused by over voltage or over-voltage operation.
Contact us if you need more details on Over-Voltage Protector. We are ready to answer your questions on packaging, logistics, certification or any other aspects about a. C. Power System、Lightning Arrester. If these products fail to match your need, please contact us and we would like to provide relevant information.
Product Categories : MOA Without Gaps