The Full-Form of MCB - Miniature Circuit Breaker
What is MCB short answer?
MCB stands for miniature circuit breaker. An MCB is an electrical switch that is automatically controlled to protect an electrical circuit from damage caused by excess current from an overload or short-circuiting. The main function is to interrupt current flow until a fault has been found.
They are specially designed to trip during an overload or short circuit to protect against electrical faults and equipment failure. MCB is widely used as protecting components in domestic, commercial, and industrial settings.
MCB Types and Uses
We will talk about Types of MCB because MCB has been divided into many types. Such as type B, type C, type D, type K, and type Z. We will talk about all these in this article.
Why it is important to know the types of MCB?
MCB is the most used circuit breaker. Therefore, questions related to this are asked a lot in interviews. MCB protects our system in case of short circuits and overload. But our electrical equipment comes in many types, due to this, the types of MCB have also been divided according to the equipment.
What are the Disadvantages of installing the wrong type of MCB?
You can understand this very easily. If ever we put type D MCB in our house, and there is a fault in the house. Like overload, our equipment will get damaged due to this but Type D MCB will not trip either.
Therefore, if ever MCB is to be installed for home appliances, then at that time use type B MCB only. Apart from this, you can also install type C MCB.
Types of MCB available in the Indian Market
MCB is divided into 5 parts based on tripping characteristics.
- B type
- C type
- D type
- K type
- Z type
The only difference between all these types of MCB is that all these MCB trips at different times due to fault in the system.
 |
| MCB different tripping current table |
Now let us understand the work of all these MCB and their use one by one.
Type B MCB - This MCB is mostly used for home appliances.
If a current of 3 to 5 times its capacity comes out from the B type MCB, then it will trip in between 0.04 seconds to 13 seconds.
Applications: residential, commercial, and industrial.
Type C MCB- This is the most used MCB, it is used a lot in both homes and companies. Well, this MCB is designed for an AC induction motor. But it can also be used at home.
Type C MCB working and use
If a current of 5 to 10 times its capacity comes out from type C, then it will trip in between 0.04 seconds to 5 seconds.
Applications: residential, commercial, and industrial.
Type D MCB - This MCB is used where a large amount of current is getting less and less frequently. For example, you can understand with a welding machine. Because the welding machine runs intermittently.
On this type of equipment, we use type D MCB.
If a current of 10 to 20 times its capacity comes out from the D type MCB, then it will trip in between 0.04 seconds to 3 seconds.
Usage- welding machine, x-ray machine in hospitals
The important thing- Please never put type D MCB at home, it will not provide any protection on home appliances, because this MCB is made for high fluctuating current equipment.
Type K MCB - This MCB is also called sensitive MCB because it trips in a very short time.
If 8 to 12 times of its capacity current comes out from K type MCB. Then it will trip in less than 0.01 second, meaning it trips in less than 1 millisecond and gives us protection.
Type Z MCB - This MCB is called a highly sensitive MCB. Because it trips in a very short time, but at the same time gives protection to our system by sensing very small faults.
If 2 to 3 times current comes out of type Z MCB above its capacity, then this MCB will also trip in less than 0.01 second.
We can never use Z Type and K Type on our home load or motor.
Both these MCB are used in that place. Where even a little too much current can damage our equipment.
Example- semiconductor devices, transistors, etc.
Which type of MCB is used in the homes?
The best MCB suited for domestic appliances is type C, where the current load is medium. Type C MCBs trips off when the flow of current is 5-10 times more than normal.
Any Questions related to this topic please feel free to ask me on my other social media accounts.
Thank You!
Happy Learning!
