What's the function of the current transformer.

In the power generation, transformation, transmission, distribution and electricity lines, the size of the current varies from a few amps to tens of thousands of amps. For the convenience of measurement, protection and control, it needs to be converted to a relatively uniform current. In addition, the voltage on the line is generally relatively high, so it is very dangerous to measure directly. Current transformers play the role of current conversion and electrical isolation. For pointer type ammeter, the secondary current of current transformer is mostly amperage (such as 5A). For digital instruments, the sampled signal is generally of milliampere level (0-5V, 4-20mA, etc.). The secondary current of the miniature current transformer is at milliampere level, and it mainly acts as a bridge between the large current transformer and sampling.

In order to ensure the safe and economical operation of power system, it is necessary to monitor and measure the operation of power equipment. However, the general measuring and protection devices cannot be directly connected to the primary high voltage equipment, and the large current of the primary system needs to be converted into small current in proportion to provide the measuring instruments and protection devices for use.

When measuring the high current of alternating current, the secondary instrument measurement needs to be converted to a relatively uniform current (the secondary rating of current transformers is set as 5A or 1A in China). In addition, the voltage on the line is relatively high, which is very dangerous to measure directly. The current transformer acts as current converter and electrical isolation. It is a sensor for secondary equipment such as measuring instruments and relay protection to obtain the current information of the electrical primary circuit in the power system. The current transformer converts high current into low current in proportion. The current transformer is connected to the primary system at the primary side, and the measuring instrument and relay protection are connected to the secondary side.

Therefore, current transformers can be divided into measuring current transformers and protection current transformers; The purpose of the measuring current transformer is to measure (charge) and measure the current of the operating equipment. The current transformer for protection is mainly cooperated with the relay device to provide signal to the relay device to cut off the fault circuit in case of fault such as short circuit and overload, so as to protect the safety of the power supply system.

    

We manufacture various precision current transformers and voltage transformers, which are widely used in electric power, energy, telecommunication, railway, industrial control and other fields.

If you have any needs, pls be free to contact us, we welcome customers to customize.

Email: sales008@mycoiltech.com

Sales engineer: Bob Bao

Tel: +86 551 6291 5885