Everything You should Know about Miniature Circuit Breakers

Miniature circuit breakers are now found all over the world, and for good reason. These small and compact circuit breakers serve as protection for various electrical circuits, and they are easy to install and maintain as well. But if you are thinking of using MCBs for your electrical installations, it pays to know as much as you can about them – and their advantages. Here, then, is everything you should know about miniature circuit breakers and how they can benefit you.


What are they and what is their function?

MCBs are electro-mechanical devices which are specially-designed to protect electrical circuits from overloading. MCBs also protect against a variety of electrical faults and short circuits. MCBs can be found in different current ratings, and this versatility allows MCBs to protect a number of electrical loads. MCBs are used for fire prevention and the prevention of electric shock, since MCBs have the capacity to interrupt dangerous electrical currents, preventing them from melting the wiring’s insulation.

How they are constructed and how they work

MCBs are equipped with a thermal barrier or protection which protects them against situations involving overcurrent. A typical MCB will have a bi-metallic contact which can expand when coming into contact with heat, and it is also calibrated to interrupt or trip the MCB if the rated current goes beyond normal for whatever reason. MCBs also have a special magnetic cover or protection when it comes to electrical faults. This is especially useful since electrical fault currents are often higher and can bring more harm. MCBs are fitted with a mechanism that allows for manual interruption, and this allows an electrician to disconnect an electrical circuit for reasons such as retro-fitting, maintenance, or new equipment installation. 

MCBs compared to MCCBs and fuses

The moulded case circuit breaker, or MCCB, is another device used for electrical protection similar in internal workings to the MCB since they are both circuit breakers which are magnetic and thermal. But there are some distinctive differences as well: MCCBs are larger than MCBs, and the current ratings of MCBs are at less than 125 amperes, whilst the current ratings for MCCBs can be as high as 2500 amperes. But the miniature circuit breaker is easier on the budget than MCCBs.

The fuse, on the other hand, is also a protective device for electrical installations, but it operates on an entirely different code or principle. MCBs can disconnect the electrical circuit if there is an overload or fault, and they will not be damaged. The only way an MCB can become damaged is if it goes through a particularly severe overload or fault. Meanwhile, fuses are only able to protect an electrical circuit one single time. Rather than tripping, a fuse will interrupt the electrical circuit through the process of burning out. Because of this, fuses have to be thrown out and then replaced with an entirely new one whenever there is an electrical fault.


Image courtesy of jk1991/FreeDigitalPhotos.net





Leave a Reply

Your email address will not be published. Required fields are marked *