100V equipment works according to the principle of electromagnetic induction, but its electromagnetic structure relationship is exactly the opposite of that of current transformers. The secondary circuit of the voltage transformer is a high-impedance circuit, and the magnitude of the secondary current is determined by the impedance of the circuit. When the secondary load impedance decreases, the secondary current increases, so that the primary current automatically increases by one component to satisfy the electromagnetic balance relationship between the primary and secondary sides. It can be said that the voltage transformer is a special transformer with a defined structure and form of use.

Precision voltage transformers are instruments used in electrical testing laboratories to expand the limits and measure voltage, power and electrical energy. Voltage transformers and transformers are very similar, and are used to convert voltages on lines. However, the purpose of transformer voltage conversion is to transmit electricity, so the capacity is very large, generally in kilovolt acc or megvolt acc. The purpose of transformer voltage conversion is mainly to supply power to measuring instruments and relay protection devices, used to measure the voltage, power and electrical energy of the line, or to protect valuable equipment, motors and transformers in the line when a line fails. Therefore, the capacity of voltage transformers is very small, generally only a few volt acc or dozens of volt acc, and the maximum is no more than one thousand volt acc .

? 220V 380V If the voltage transformer is connected to the line to convert the voltage, the low voltage and high voltage voltages on the line can be converted into one or several low voltage voltages in the corresponding proportions. As long as one or more voltage specifications of instruments and relays, such as general voltage meters, the voltage on the line can be measured and monitored through the voltage transformer.