ELCB and MCCB

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MCCB have thermal overload which provide tripping commend if temp. increasde with increase in current(load).Normally in amp(2amp to 1000 amp)

ELCB check leakage current between earth & nutral , it is normally in miliamps (30mamp or 100 mamp).

MCCB = Molded Case Circuit Breaker

additional idea for Guest idea,

MCCB used to protect circuit from short circuit and overload. MCCB can be modified with relay 50/51. this 50/51 relay get input from CT, and ouput from this CT can trip MCCB (of course, we must add shunt trip in this MCCB).

for ELCB, as long as i know ELCB used in 1 phase. for three phase, we use Zct. Secondary cable from Zct goes to 50G relay. and then 50G relay makes contactor trip. or 50G relay makes MCCB (complete with shunt trip) trip.

Zct is CT with 1 hole. all of three cables(R,C,T) goes through this 1 hole.

MCCB are curent limiting devices which function in two ways

1) relay tripping for short circuits

2) thermal tripping for overloads

ELCB are monitering the earthleakage currents and in an evant of earth current flowing it will trip they come in sensitivity of 30ma and 60 Etc

Normally recommended in areas of high earth resistance where the MCCB will delay in tripping.

Dear Friend ,

This is a basic question which has answers in the net if you surf a little in google.Please read the following links and come out with doubts if you have any one. In CR4 this was discussed many times earlier. Take a little pain to read the earlier threads. it will help you in understanding the subject if you decide.

http://www.allinterview.com/showanswers/61375.html

http://en.wikipedia.org/wiki/Earth_leakage_circuit_breaker

http://in.answers.yahoo.com/question/index?qid=20080308001048AAgQjG2

elcb meains earth tripped good safety equipment

mccb meains short circuit &over load tripped

Internet search engines can provide this. So can telephone calls to the equipment manufacturers.