What is the difference between MCCB and RCCB?


MCCB - Moduled Case Circuit Breakers

MCCBs protect against over current and short circuit.

Some MCCBs are designed with inbuilt residual protection.

An MCCB isolate the circuit whenever it senses any short circuit or prolonged overload in the device or circuit it protects.

Overload rating of MCCBs can be varied from 40 to 70 percent of its rated value.

Some MCCBs comes with inbuilt residual current / earth fault protection

Residual current values of MCCBs with LSIG can be varied from 10 ma to 30 ma

MCCbs are available in single pole,two pole,three pole, and four pole version up to the rating of 2500 A.

RCCB - Residual current Circuit Breaker

Residual current circuit breaker are used to provide protection against electrical shocks.

In healthy circuit,line and neutral current will be balanced always.

Whenever there is some leakage in the circuit or in case of any earth leakage in the circuit,there will be an imbalance between the line and neutral current.

These imbalance can also be caused due to electrical shock.

RCCB senses such imbalances and trip the circuit.

RCCBs cannot provide protection against short circuit.Also short circuit can even damage RCCB

Hence it is recommended to use RCCBs along with short circuit protection devices such as MCB or MCCBs to protect them against short circuit.

RCCBs are available in two pole and four pole versions with an ampere rating of up to 160 A with a residual trip current rating of 300 mA