The function and principle of current transformer

Update:09-01-2021
Summary:

The role of current transformers: the currents vary gre […]

The role of current transformers: the currents vary greatly in the lines of power generation, transformation, transmission, distribution and power consumption, ranging from several amperes to tens of thousands of amperes. In order to facilitate measurement, protection and control, it needs to be converted into a relatively uniform current. In addition, the voltage on the line is generally relatively high, such as direct measurement is very dangerous. The current transformer plays the role of current conversion and electrical isolation.

A current transformer is an instrument that converts a large current on the primary side into a small current on the secondary side based on the principle of electromagnetic induction. The current transformer is composed of a closed core and windings. Its primary winding has a few turns and is stringed in the circuit of the current to be measured. The principle of current transformer is based on the principle of electromagnetic induction. The current transformer is composed of a closed core and windings. Its primary winding has a few turns, which is stringed in the line of the current that needs to be measured. Therefore, it often has all the current flowing through the line. The secondary winding has a large number of turns. It is serially connected to the measuring instrument and the protection circuit, and the current mutual inductance When the transformer is working, its secondary circuit is always closed, so the impedance of the series coil of the measuring instrument and the protection circuit is very small, and the working state of the current transformer is close to short circuit.

Ankerui Electronic Commerce (Shanghai) Co., Ltd. M8 current transformer has a small primary current and is mostly used in relay protection circuits, suitable for low-voltage drawer cabinets and other small spaces. It is used to collect low-voltage overload and short-circuit signals, and is used with protection relays and motor protectors.