October 2, 2023

Miniature Circuit Breaker (MCB) – An Overview

Every household, factory, or building that uses electricity will likely have an MCB. MCB is as necessary for your house’s electrical infrastructure as windows and doors. But what makes an MCB so important, and how do you select the right one? 


Well, this is all that we are discussing in this article. So, continue reading to get answers to all your questions regarding your electrical infrastructure. 

What Is Mcb?

A miniature circuit breaker (MCB) is an electrical switch that self-operates and provides protection from electrical shocks caused by current overload or short circuits. It breaks the circuit if the current flow is above the usual limit. In the use and use of electricity for domestic, commercial, and industrial purposes, MCB is a trustworthy form of protection.


The MCB is a fantastic alternative to the fuse since it automatically opens when there is an excessive current flow and closes automatically once the circuit current is at the standard rate. It eliminates the need for manual replacement.

 How Does An Mcb Work?

The MCBs operate on two mechanisms: the thermal tripping effect and the magnetic tripping effect. The thermal operation uses bimetallic strips that are made of brass and steel and are used to provide time delays during overloads.


In contrast, the magnetic tripping system consists of one magnetic pool with a spring-loaded dashpot and magnetic slug in a silicon fluid and another normal magnetic pool. In cases of short circuits or heavy overloads, it helps to attract the armature of the trip lever and neutralise the current.

 Types Of Mcb 

The Miniature Circuit Breakers (MCB) are categorised into three parts:

  •  Type B MCB 

These MCBs trip and signal instantly once the current rate increases three to five times the normal rated current. Type B MCBs are found in residential and small commercial buildings.

  •  Type C MCB 

The type C MCB trips instantly if the current flow exceeds five to ten times its rated current. It can handle high short-circuit currents and is thus suitable for commercial and industrial installations.

  •  Type D MCB 

It trips when the current flow exceeds its rating by ten to twenty-five times. It is adequate for large industrial and commercial areas with high inductive loads.

 MCB Vs. MCCB <h2/>

Often, buyers need clarification on MCBs and MCCBs and their respective purposes. So, let’s put those worries aside and learn about MCCBs and how they differ from MCBs. 


An MCCB stands for Molded Case Circuit Breaker. MCCBs have adjustable trip characteristics, and they are used in high circuits. Their interrupting rating ranges from 10,000 to 20,000 amps and is suitable for high-power industries.

How To Buy The Right Electrical Infrastructure?

The MCBs or MCCBs are an essential part of the electrical infrastructure of any household or commercial space. They protect from electrical shocks, fires, and other hazards. 


Therefore, purchase the ones that fit your existing energy distribution set-ups and offer high-quality certification standards.


To shop for high-quality MCBs and MCCBs, visit Legrand today!