1- MPCB-Motor Protection Circuit Breaker:

MPCB is the electromechanical protection device which is specially designed for motor protection. It is combination of two function like as one is adjustable overload relay and circuit breaker. It is the latest device of motor protection. Generally overload and circuit breaker are used as separately.

2- Circuit diagram of MPCB:

3- Working principle of MPCB:

First of all we will discuss about the function of MPCB. It is the combination of circuit breaker and overload relay. So we can categorized MPCB function in two types, one is circuit breaker function and overload relay function.

Circuit Breaker Function:

Circuit breaker is a switching device accept this it provides us protection against below mentioned details.

• Short circuit protection
• Over current protection
• Line protection

Overload relay function:

Overload relay is used for motor protection just like as below mentioned.

• Overload protection
• Protection against phase loss
• Current adjuster as per capacity
• Ambient temp

4- Benefits of MPCB:

MPCB is the combination of two electrical device. It is initial cost is more but other benefits are more as below mentioned detail.

• Compactness
• High breaking capacity
• Protective coordination of short circuit
• Wiring work reduction
• Design standard is ecological

5- Types of MPCB:

1. According to Phase:
   • Single Phase
   • Three Phase
2. According to Motor capacity:
   • Single phase motor capacity
   • Three phase motor capacity
3. According to protection devices:
   • Thermal and Magnetic protection
   • Magnetic protection

6- Why MPCB is used:

MPCB is specially designed for motor protection because in around us the motor are used a lot off just like as domestic and industrial. It is a compact design in place of breaker and overload relay as reducible wiring and equipment. It has additional safety features are inbuilt as phase loss etc.

Go back to index ↑

---