How to maintain the mini circuit breaker？

The MCB is a device that many people have access to, but not all of them know how to use it safely. How does a circuit breaker work? What is the function of the mini circuit breaker?

• What is the purpose of a circuit breaker?

• How does a circuit breaker work?

• How do I maintain the MCB?

What is the purpose of a circuit breaker?

A micro circuit breaker is a small capacity plastic case circuit breaker with a very compact structure. It is a branch of low voltage circuit breaker and has become a large category of terminal appliances. Micro circuit breakers are used to protect electrical appliances, mainly to protect circuits and equipment safety. When the circuit or electrical equipment overload, short circuit and other faults, the tripping device should be able to timely action, reliable cut off the circuit; When the circuit or electrical equipment is in normal condition, the main contact should be able to connect the circuit reliably, and the release should not fail. The main fault modes of MCB are operation fault, misoperation fault, and rejection fault.

How does a circuit breaker work?

The short circuit protection function of mini-circuit breaker is realized by instantaneous trip. The instantaneous trip is connected in series in the circuit and the coil turns are few (usually less than 10). According to F=IN analysis (suction is proportional to the product of the current and the number of turns), when the circuit works normally, due to the small number of turns, the suction generated by the normal working current is not enough to overcome the spring reaction force, so the circuit can work normally. When the circuit is short or seriously overloaded, a large current flows through the induction coil, generating a strong magnetic field. The number of turns of the coil remains the same, but the current is increased by several or tens of times, so the suction is increased by several or tens of times. Pushing the lever will cause the circuit breaker to trip rapidly due to current. The current is very large, and the trip time of the circuit breaker is usually within 0.1s.

How do I maintain the MCB?

1. Dust should be removed from the circuit breaker regularly, and the action value of various tripping devices should be checked. The operating mechanism usually fills the transmission part with lubricating oil every two years.

2. After breaking the short circuit current or long-term use, metal particles and black smoke on the wall and gate of the arc extinguishing chamber should be removed to maintain good insulation and arc extinguishing performance.

3. It is not allowed to take off the arc extinguishing cover during the operation. If damaged, it should be replaced in time to avoid short-circuit failure to extinguish the current accident.

4. If the MCB is disconnected due to a fault of the protected circuit (leakage, overload, or short circuit), the operating handle should be in the trip position (middle position). After finding out the cause and troubleshooting, pull down the operating handle (that is, put it in the "off" position) and make the operating mechanism "buckle" again before closing the MCB handle (note the different meanings of the three positions).

If you are looking for mini circuit breaker with good quality and reasonable price, Zhejiang Chinehow Technology Co., Ltd. can provide you with the best.