金属氧化物避雷器的工频参考电压如何测量？工频参考电压是无间隙金属氧化物避雷器的一个重要参数，它表明阀片的伏安特性曲线饱和点的位置。运行一定时期后，工频参考电压的变化能直接反映避雷器的老化、变质程度。
How to measure the power frequency reference voltage of MOA? Power frequency reference voltage is an important parameter of gapless MOA, which indicates the position of saturation point of V-A characteristic curve of valve plate. After a certain period of operation, the change of power frequency reference voltage can directly reflect the aging and deterioration degree of arrester.
所谓工频参考电压是指将制造厂规定的工频参考电流(以阻抗电流分量的峰值表示，通常约为1~20mA)，施加于金属氧化物避雷器，在避雷器两端测得的峰值电压，即为工频参考电压。
The so-called power frequency reference voltage refers to the power frequency reference current specified by the manufacturer (expressed by the peak value of impedance current component, usually about 1 ~ 20mA) applied to the metal oxide arrester, and the peak voltage measured at both ends of the arrester is the power frequency reference voltage.
由于在带电运行条件下受相邻相间电容耦合的影响，金属氧化物避雷器的阻抗性电流分量不易测准，当发现阻性电流有可疑现象时，应测量工频参考电压，它能进一步判断该避雷器是否适用于继续使用。
Due to the influence of capacitance coupling between adjacent phases under the condition of live operation, the impedance current component of metal oxide arrester is difficult to measure accurately. When the resistance current is found to be suspicious, the power frequency reference voltage shall be measured, which can further determine whether the arrester is suitable for continuous use.
判断的标准是与初始值和历次测量值比较，当有明显降低时就应对避雷器加强监视，110kV及以上的避雷器，参考电压降低超过10%时，应查明原因，若确定是老化造成的，宜退出运行。
The judgment standard is to compare with the initial value and previous measured values. When there is a significant reduction, the arrester shall be monitored more closely. When the reference voltage of the arrester of 110kV and above is reduced by more than 10%, the cause shall be found out. If it is determined that it is caused by aging, it is better to quit the operation.