Views: 22 Author: Site Editor Publish Time: 2023-01-16 Origin: Site
The residual current circuit breaker realizes the protection action by detecting the current vector sum of the phase line and the current difference between the neutral line and the neutral line. The sensitivity is higher than that of the zero-sequence protection. Generally, it has two purposes. One is to prevent fire (300~500MA), and it is used for trunk lines.
What is the main structure of residual current circuit breaker?
What is the function of residual current circuit breaker?
What is the difference between residual current circuit breaker and circuit breaker?
For the residual current circuit breaker, the upper line means that the power line passes through the connecting plate - static contact - moving contact - soft connection - protection system (bimetal element or heating resistance element and electromagnet system) - connecting plate; The line is the power line-connecting board-protection system-soft connection-moving contact-static contact-connecting board. When the line is fed down, if the short-circuit current is interrupted, although most of the arc enters the arc extinguishing chamber, there is always a part of the charged free gas moving to the connecting part of the moving contact, and the free gas of a certain phase is in contact with the charged body of the adjacent phase. Phase-to-phase short circuits may occur. On the other hand, even if the residual current circuit breaker successfully breaks the short-circuit current, due to the lower wiring, the protection system, soft connection, and common shaft are always under the power supply voltage (although no current flows), which will cause the insulation to age, and also Accidents such as creepage between phases may occur.
When the phase line of the protected line is connected to the ground directly or through an unexpected load, an approximate sinusoidal waveform is generated and its effective value is a slowly changing residual current. When the current is greater than a certain value, the residual current circuit breaker cuts off the line. to maintain. Residual current protection: The installation of residual current action protectors in low-voltage power grids is an effective protection measure to prevent personal electric shock, electrical fire and damage to electrical equipment. Leakage current is a kind of residual current. The meaning of residual current covers leakage current, but the essence of the two is consistent with the protection principle.
The difference between residual current circuit breakers and circuit breakers: residual current circuit breakers have leakage protection functions, and some also have short circuit protection and overload protection functions;
The circuit breaker has overload protection and short circuit protection functions, but no leakage protection function.
The biggest difference is that the former can play the role of leakage protection, while the latter cannot.
It is very dangerous when the equipment used is leaking, so a residual current circuit breaker is required.
After reading, do you have a deeper understanding of residual current circuit breaker? For further information, please contact JIELI Electrical. They will be very pleased to help you.