Define circuit breaker

Here you learn about that what is circuit breaker and types of breaker, with about its working principle.

 What is circuit breaker?

The circuit breaker is use for protection purpose. It protects electrical equipment and machines in the short circuit or overload's condition. Its basic function is interrupt current flow after a fault detect. If the current flows over from its capacity then will be trip, and circuit will open means circuit will “OFF”. So that appliances or machine be safe. The circuit breaker is always used in any one wire's series like neutral and phase wire. And it used always in main supply.

          When do any short circuit it give protect. In short circuit condition flow of current will increase. So circuit breaker sense it and automatic trip, for this circuit will open and wires be safe from fire. If we circuit breaker not use in electrical wiring, so we will get harmed, and wiring be burnt. The circuit breakers tripping time is 1/100 sec.

Other advantage of circuit breaker has if it tripped. Then we can easy to reset in “ON” condition, but if it be tripe means have any problem in the circuit. So we needs check our system or circuit then reset (ON) the circuit breaker.

The Circuit breaker is available in different capacity in the market. Because it use on need base, means how much amperes (Current) we need for our load, and its capacity measure in ampere.

Circuit breaker is most important device for home and industries. And we can use it for an "ON" "OFF" switch like a switch button, because it is easy for “On” or “Off”.

The circuit breaker we can use in "AC" and "DC" both of them, but "AC" or "DC" Breaker is different. Not every breaker can be use in either of these. Because its coil is design different, the "AC” circuit breaker operates at high voltage. While "DC" circuit breaker operates at low voltage.

Advantage in the overload's condition:-

Example:-

A motor is normal running at “10” ampere current. But suppose, the Motor's windings comes a fault and it take high current like 15-20 Ampere. This is overload's condition so circuit breaker will be trip and give protect to motor from Burnt or fire. Because it windings support only 10-12 ampere. But if high amount of current will flow from windings, then wire get heat quick and winding can burn.

 

Types of circuit breaker:-

There are “5” most useful circuit breaker

               1- MCB (Miniature Circuit Breaker) 

The MCB is a safety device that protects our devices or circuits from damage. On the event of a short circuit or overload's condition, because in the event of a short circuit or overload. Excessive current flows into the devices so can damage the devices.

This type circuit breakers capacity is 2-100 ampere. And this is available like 8, 16, 32, 64 ampere etc. Its uses depended on load that how much ampere we need for our equipment.

When MCB feels excessive current, then it will trip. And its most used on place of fuse. The Miniature Circuit Breaker common used in house distribution box. Such in panel board where electricity comes from.

2- MCCB Molded Case

This type circuit breaker absolute work like “MCB” but it use for heavy load. Such as industries or where need high amount of current.

It is design for heavy duty, its current capacity from 80 ampere to 1000 ampere. It’s also use for protection like overload or short circuit condition. It not has other difference; it has only different of ampacity.

3- MPCB Motor Protection Circuit Breaker

This type circuit breaker most use for motors protection. It is different from other circuit breaker, like “MCB” or “MCCB”.

The MPCB flow high current for some seconds, because any Motor take high current at starting time. But if current flows have remained then it will sense that done short circuit or over load and MPCB will off. MPCB also protect the motor against phase loss or imbalance condition. In MPCB we can set over current on need, for this MPCB breaker more use in motors,

Suppose a motor’s normal current is 10 ampere, but starting current is 14-15 ampere. This circuit breaker flow this current. But normal circuit breakers like “MCB” will quick off and motor can’t start.                          

4- RCCB Residual Current

This type circuit breaker protect only against electric shock and earth leakage condition. The RCCB has not short circuit or over load protection. It use with MCB or MCCB in the house distribution box, because this type breaker will protect to us.

Example:-

In our home we use electric appliances such as electric Iron or electric Geyser etc.

If any fault comes to it and current leakage in its body. so if we touch it so we get electric shock, so RCCB protect in this condition.

The RCCB operates by “Kirchhoff's” law, it sense outgoing current and incoming current. If it senses that both current is unequal then it will trip.

5- RCBO Residual Current Breaker With Over Load

This type circuit breaker is combination of above two type’s circuit breakers, such as “MCB” and “RCCB”. Means RCBO will protect against short circuit overload and earth leakage condition.

 Which circuit breaker how many current can support?

This rating wrote in ampere on any circuit breaker. And current capacity set by manufacturer; we can’t change its capacity. Most 8 or 16 ampere’s circuit breaker we use in home wiring.

Working principle of Electrical circuit breaker?

Inside circuit breaker has two copper plates which connect or disconnect. When plates connect to gather so circuit will complete. And when plates disconnect then circuit will open, means off.

How circuit breaker will automatic off in short circuit condition?

The circuit breaker works by electro magnet. Circuit breaker has one coil where current pass through, and below coil a solenoid rod. When current increase its capacity so magnet will increase with changing of current. If magnet increase then solenoid rod will down, and if solenoid rod will down so it pull down the copper plate. If plate go down then circuit breaker will off.

 

THE END