Explain MCB and ELCB with connection diagram supplying single phase load.

Explain MCB and ELCB with connection diagram supplying single phase load. 
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1 Answer

Answer :

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OR

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Explanation:

* MCB provides short circuit protection.

* MCB provides overload protection

* ELCB provides earth fault protection.

* MCB is in series with load and ELCB is across the supply.

ELCB:-

 An Earth Leakage Circuit Breaker (ELCB) is a device used to directly detect currents leaking to earth from an installation and cut the power and avoid the person from getting shock.


There are two types of ELCBs:

 1. Voltage Earth Leakage Circuit Breaker (voltage-ELCB)

2. Current Earth Leakage Circuit Breaker (Current-ELCB). 


OR


Earth leakage circuit breaker is a safety device used in electrical installations with high earth impedance to prevent shocks and disconnect power under earth fault conditions. Works on principle of relaying when the current in the earth path exceeds a set value. ELCB is used for protection against electric leakage in the circuit of 50 Hz or 60 Hz , rated voltage single phase 230 V, 3 ph. 400 v. Rated current up to 60 Amp. When the earth fault occurs, the ELCB cuts off the power within the time of 0.1 sec. automatically to protect the personnel. 

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