What should we consider before buying an MCB?

Knowing what a miniature circuit breaker is can help you determine if it is beneficial to your electrical system. MCB has implications for the life safety and safety of expensive wiring in home offices and industry. What should we consider before buying an MCB?

l What is the internal structure of the MCB?

l How does a miniature circuit breaker work?

l What is the importance of matching MCB to load?

What is the internal structure of the MCB?   

In short, the MCB has a dual safety trip element. One is a bimetallic element that heats up and trips to disconnect the power supply under overload conditions, and the other is an electromagnetic coil that acts and trips to disconnect the power supply in the event of a short circuit or a spike that exceeds its rated current. The quality varies depending on the type of bimetallic elements, sprint actuators, metal parts and coils. These must be of high quality to work as prescribed. Contact metal components need to be of high quality to prevent spark corrosion since sudden disconnection always produces sparks that can corrode the contacts. Some of the best MCBs use silver alloys. The metal parts should be sufficiently rigid, and spring quality is also important for fast operation. In addition, you want the structure to be strong and well treated to withstand rust that can impede movement. It's the small, important things that really matter.

How does a miniature circuit breaker work

1. In case of overload, more than the rated current is driven through the MCB. When an electric current flows through the bimetal, it heats up and bends, deflecting it and releasing the mechanical latch. The deflection time of the bimetallic sheet depends on the amount of current flowing through the sheet. The higher the current, the faster the bimetal will deflect.

2. During a short circuit, the transient current flowing through the solenoid forces the plunger toward the latch. This action instantaneously releases the mechanical latch and immediately opens the contact.

What is the importance of matching MCB to load?

It is important to match the MCB to the load. It is easy to calculate the load by looking at the power rating of each appliance and equipment connected to the line through the MCB switchboard. The current can be found by dividing the watt by the voltage. Add current for all possible devices. You may not use all devices at once. However, exercise caution or choose 80% of the total current of all devices. Overestimate this by 25%, so that if your load current is 10 A, you choose an MCB rated at 12A. Do not choose the MCB with lower amps to save money, as it will trip frequently. Do not make the mistake of thinking that you will be safe if you put in A 30 A MCB in this situation.

If you are looking for a supplier of high quality miniature circuit breakers at a reasonable price, the Singi Electrical is a very good choice. Our website is https://www.singi.com/. We are looking forward to cooperating with you. Years of accumulated R&D and production experience will provide you with more product services and technical support! Our company adheres to the corporate culture of "quality-oriented, customer first", and has always made unremitting efforts to become a professional metal detector supplier in the industry.