国产一级毛片av_日韩经典天堂v色_午夜黄片在线播放_边做边流奶水的人妻_亚洲特片国产精品_国产AV无码专区亚洲AV手机麻豆_思思精品热中文字幕_黄色毛片成人免费观看_国产午夜av在线_欧美久久成人精品

The commonly used connection modes of voltage transformer are:The main results are as follows: (1) single connection can be used to measure the line voltage of the system whose neutral point is not directly grounded below 35kV or the relative groundi

The working principle of voltage transformer:Its working principle is the same as the transformer, and its basic structure is iron core, original winding and secondary winding.Its characteristic is that the capacity is small and relatively constant,