"ED"(low-voltagelinebutterflyinsulator)"—"Thenumberafter"—"istheordinalnumberofshapeandsize,and1isthelargestsize.Themainfunctionistoachieveelectricalinsulationandmechanicalfixation.Kindofelectricalandmechanicalperformancerequirements.Ifunderthespecifiedoperatingvoltage,lightningovervoltageandinternalovervoltage,nobreakdownorflashoverwilloccuralongthesurface;inthespecifiedlong-termandshort-termUndertheactionofmechanicalload,nodamageordamagewilloccur;afterlong-termoperationunderspecifiedmechanicalandelectricalloadsandvariousenvironmentalconditions,noobviousdeteriorationwilloccur;Itdoesnotproduceobviouscoronadischargeundertheoperatingvoltage,soasnottointerferewithradioorTVreception.Becauseinsulatorsarewidelyuseddevices,theirconnectionfittingsarealsorequiredInterchangeable.Inaddition,thetechnicalstandardsforbutterflyinsulatorsED-1alsore