互感器包括电压互感器和电流互感器
Mutual inductor includes voltage transformer and current transformer.
电压互感器是一种电压变换装置，有电压变换和隔离两重作用，它将高压回路或低压回路的高电压转变为低电压（一般为100V），供给仪表和继电保护装置实现测量、计量、保护等作用。
Voltage transformer is a kind of voltage conversion device, which has dual functions of voltage conversion and isolation. It transforms the high voltage of high voltage circuit or low voltage circuit into low voltage (generally 100V), and supplies instrument and relay protection device to realize measurement, measurement and protection.
电流互感器是一种电流变换装置，有电流变换和隔离两重作用，它将高压回路或低压回路的大电流转变为低压小电流（一般为5A），供给仪表和继电保护装置实现测量、计量、保护等作用。
Current transformer is a kind of current conversion device, which has the dual functions of current conversion and isolation. It transforms the large current of high voltage circuit or low voltage circuit into low voltage and small current (usually 5A), and supplies instrument and relay protection device for measurement, measurement and protection.
实际测量时，为了更好的与仪表量程匹配，也有将5A以下小电流变换为大电流（5A）的互感器。
In actual measurement, in order to better match the instrument range, there are also transformers which convert small current below 5A into large current (5A