氧化锌避雷器用传统数轮计数型监测器下限动作灵敏度研究

Study on Lower Limit Action Sensitivity of Conventional Counting Type Monitor for Zinc Oxide Surge Arresters

金属氧化物避雷器用监测器串接于避雷器接地端,用于记录避雷器的动作次数和泄漏电流。在机械行业标准JB/T 10492-2011中规定了监测器的下限动作电流为50 A,波形为8/20μs,此项要求以动作性能试验进行性能判定,且被列入型式试验及验收试验项目。对数轮式机械计数型监测器在不同波形下的下限动作临界电流幅值及多位数字轮计数器在进位过程中最低动作电流幅值下的动作性能进行研究。结果表明:传统数轮计数型监测器下限动作灵敏度与通过监测器的波形和数轮计数器数轮位数有关,波形持续时间越长,数轮位数越少,灵敏度越高。

The MOA monitors are connected to the grounding end of the MOA in series to record the action times and leakage current of the MOA.According to JB/T 10492-2011,the lower limit action current of the monitor is 50 A and the waveform is 8/20μs.This requirement is judged by the action performance test,and is included in the type test and acceptance test items.The author studied the minimum operating current amplitude of several-wheel mechanical counting monitor under different waveforms,and also researched the action performance of multi digital wheel counter under the minimum operating current amplitude in the process of progressing.The results show that the lower limit action sensitivity of traditional digital wheel counting monitor is related to the waveform of the monitor and the number of wheels of the counter.The longer the waveform duration,and the fewer digits,the higher the sensitivity.