Thursday, September 1, 2016

3 Pole - 4 Pole MCCB Wiring Diagrams and Installation

As you know that there are different types of circuit breaker , in those circuit breaker a well known name is mccb which molded case circuit breaker and in this post you will learn about the mccb wiring and initiation. in this post i am gonna to share with you two diagram of mccb in which one is about the wiring of 3 pole mccb circuit breaker and other one is about 4 pole circuit breaker.
By using the the three pole circuit breaker we can control three phase power system and by using the four pole we can control 3 phase 4 wiring system. However i also share diagram about the wiring and instillation of MCB (miniature CB) and you can also read about those diagram and post by using the following links.

Also read below
How to wire 4 pole mcb
how to wire 3 pole mcb
how to wire a distribution board
How to instill mcb breakers in home wiring

How to wire Three Pole and 4 Pole MCCB circuit breakers

The wiring of mccb and mcb circuit breaker is same, and it's too simple but the difference between in mcb (miniature CB) and mccb is that we can use mcb the load between 0.5 to 100 amps and range of ampere of mccb is 1000 amps.
So if are doing a connection for distribution board which ampere is over then 100 ampere then we can not use the mcb and we must instill the MCCB.
The three pole type of molded case circuit breaker are use mostly for controlling the three phase system and this also design for that work. However we can use it for any work regarding work. If our single phase load is over than 100 ampere than we can also use this circuit breaker.
In the below mccb wiring diagram i show the complete method of wiring and installation of three pole molded case circuit breaker.

mccb wiring diagram

When we have to control a 3 phase circuit by using a breaker the first option to chose a three pole but if the circuit is three phase 4 wire system then this work can not be done with out a 4 pole circuit breaker. In the below 4 pole mccb control wiring diagram i shown the complete method of instillation and wiring of 4 pole molded case CB.

4 pole mccb wiring diagram

On thing more that if you are gonna to wire a multi storey building and instillation  three phase 4 wire system then use mccb in your main distribution board but chose your breaker regarding your total load. However further soon i will will publish post about wiring instillation in multi storey building diagrams and a guide in which i will also do the mccb wiring connection.


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  2. for 3 pole CB in vertical position with on/off Handle.... top L1,2,3 is shown as incoming power
    which is line side. I have a clear momory how to wire in old day... because on/off handle upper positon is on , so incoming live power wire should connect to bottom L1,2,3 and Load wire to the top L1,2,3. what happened is this wrong now.
    For power Panel board, you should wire like your picture. but incoming power live wire to
    any power circuit breaker, Line side live wire to the bottom L1,2,3,
    Am I wrong ? can anyone answer my question / this was done because of safety in my knowledge.
    The top L1,2,3 shoild have voltages when close CB by close handle upward.