保定电气厂家价格-交流无间隙金属氧化物避雷器

金属氧化物避雷器的特点 

Characteristics of metal oxide arresters

金属氧化物避雷器的非线性电阻阀片主要成分是氧化锌，氧化锌的电阻片具有极为优越的非线性特性。正常工作电压下其电阻值很高，实际上相当于一个绝缘体，而在过电压作用下，电阻片的电阻很小，残压很低。但正常工作电压下，由于阀片长期承受工频电压作用而产生劣化，引起电阻特性的变化，导致流过阀片的泄漏电流的增加。电流中的阻性分量急剧增加，会使阀片上温度上升而发生热崩溃，严重时，甚至引起避雷器的爆炸事故。依照规程1规定，金属氧化物避雷器的检测项目共6项，分别为（1）绝缘电阻（2）直流U1mA及0.75U1mA下的泄漏电流（3）运行电压下的交流泄漏电流（4）工频参考电流下的工频参考电压（5）底座绝缘电阻（6）检查放电计数器动作情况。

The nonlinear resistance valve of metal oxide arrester is mainly made up of Zinc Oxide, and the resistor chip of Zinc Oxide has excellent nonlinear characteristics. At normal operating voltage, the resistance is very high, in fact equivalent to an insulator, and under the influence of over-voltage, the resistance of the resistor is very small, the residual pressure is very low. However, under normal operating voltage, the valve is subjected to the power frequency voltage for a long time, resulting in deterioration, resulting in changes in resistance characteristics, resulting in an increase in leakage current through the valve plate. The resistive component in the current increases sharply, causing the temperature of the valve to rise and cause thermal collapse, and even cause an explosion of the arrester. In accordance with the provisions of regulation 1, detection of metal oxide arrester 6, respectively (1) insulation resistance (2) leakage current of DC U1mA and 0.75U1mA (3) under operating voltage AC Leakage Current (4) frequency reference voltage power frequency reference current at the base (5) insulation resistance (6 check the electrical discharge counter).