I take an example about the design requirements for composite insulators for154kV service is set second below.
◆ Overall performance
● To have satisfactory electrical characteristics in outdoor use, and to be free of degradation and cracking of the housing
● To be free of the penetration of moisture into the interfaces of the end-fitting during long-term outdoor use
● To possess long-term tensile withstand load characteristics
● To be free of voids and other defects in the core material
● To be non-igniting and non-flammable when exposed to flame for short periods

the design requirements for composite insulators

◆ Electrical performance (insulator alone)
● To have a power-frequency wet withstand voltage of 365 kV or greater
● To have a lightning impulse withstand voltage of 830 kV or greater
● To have a switching impulse withstand voltage of 625 kV or greater
● To have a withstand voltage of 161 kV or greater when polluted with an equivalent salt deposition density of 0.03 mg/cm2
● To have satisfactory arc withstand characteristics when exposed to a 25-kA short-circuit current arc for 0.34 sec
● Not to produce a corona discharge when dry and under service voltage, and not to generate harmful noise (insulator string).

This article talked about the design requirements for composite insulators for154kV service, if you want to buy this insulator or other composite insulator, please contact Orient Power.

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