Voltage¨Current qualities of ZnO surge arresters are highly determined by temperature within the low-passing region

Voltage¨Ccurrent qualities of ZnO surge arresters are highly determined by temperature within the low-passing region. ZnO surge arresters experience thermal runaway once the temperature surpasses the appropriate limit. This phenomenon is connected using the increase of resistive leakage current because of degradation. This paper is definitely the thermal and electrical qualities of ZnO arrester blocks underneath the power frequency AC operating voltages. The leakage power of ZnO arrester blocks were measured during a period of time. The high temperature profiles of ZnO arrester blocks were observed through the infrared camera. The degradation and also the thermal runaway from the ZnO arrester blocks are carefully associated with the high temperature limit which determines heat generation and dissipation. Because the leakage current was .5mA, the quantity of heat generation is gloomier compared to heat dissipation. So temperature from the ZnO arrester blocks was rarely altered. However, because the leakage current was .7 and 1mA, the quantity of heat generation was more than those of heat dissipation. The high temperature of ZnO arrester blocks progressively increases and also the test specimen encounters thermal runaway. In those days the high temperature situated in the center of ZnO arrester blocks string was greater in comparison to that particular of ZnO block at both edges.

http://www.znoblock.com