Many of the tools in the work seem strange to the name and appearance, but they play a very important role. Without these tools, our life will become inconvenient or even unsafe, so master some The knowledge of these tools still has certain advantages. Molded case Circuit Breakers are one of them. So how do you choose a molded case circuit breaker? What is the difference between a molded case circuit breaker and an air switch?
What is the difference between a molded case circuit breaker and an air switch?
1. The air switch, also known as the air circuit breaker, is opposite to the molded case circuit breaker. Its function in the circuit is to switch on, disconnect and carry the rated working current and short circuit, overload and other fault currents, and can be in the line and load. Under the problems of overload, short circuit, undervoltage, etc., the circuit is quickly disconnected to reliably protect the circuit.
2. The molded case circuit breaker can automatically cut off the current. Under normal circumstances, the protection will be triggered automatically after the current exceeds the setting. The molded case is here to use a plastic insulator as the outer casing of the device for isolating the conductors and the grounded metal portion. The molded case circuit breaker usually contains a thermal magnetic trip unit, and the large molded case circuit breaker is equipped with a solid state trip sensor.
How to choose a molded case circuit breaker
1. First select the category according to the specific conditions of use, and then determine the specific parameters according to the rated current of the circuit and the requirements for protection. When the rated current is below 630A, the short-circuit current is not too large, and the molded case circuit breaker is preferred. The rated current is relatively large, and the frame type circuit breaker is better. It is better to replace it with those molded case circuit breakers with good performance. It should be noted that for the branch with large short-circuit current, it is necessary to calculate the current-limiting capability of the circuit breaker. This function should be used when the circuit breaker has leakage protection requirements.
There are brand-name circuit breakers of People's Electric, Delixi, Zhengtai and so on.
2. Secondly determine the type of circuit breaker, determine the parameters, is to see the price, it is the key factor of choice. Under the condition that the basic use requirements can be met, the circuit breaker should be safe and reliable, and it has good scalability. For example, it can be adjusted to adapt to the change of the future load within a certain range, and the module unit can be added to realize the function expansion.
3. The current distribution system requires that the circuit breaker be able to provide circuit control and simple short-circuit and overload protection in addition to on-off current, and also provide isolation and safety protection functions. It is reliable for personal, equipment safety and power distribution systems. Sexual aspects have put forward new requirements. Therefore, the development, design and purchase of products also focus on three aspects: personal safety, protection of electrical lines and equipment, and reliable Power Supply.
All in all, molded case circuit breakers are very important in our daily life, especially when using electrical appliances. We have some knowledge of molded case circuit breakers to help us safely and reasonably treat electrical hazards in our daily lives.