Answer / desingurajan

MCBs are miniature circuit breakers with optimum protection facilities of overcurrent only.These are manufactured for fault level of up to 10KA only with operating current range of 0.5 to 63 Amps (the ranges are fixed), single,double and three pole verson.These are used for smaller loads -electronic circuits,house wiring etc.
MCCBs are Moulded case Circuit breakers,with protection facilities of overcurrent, earth fault.it has a variable range of 50% to 100% operating current.They can be wired for remote as well as local operation both.They are manufactured for fault levels of 16KA to 50KA and operating current range of 25A to 630Amps.They are used for aplication related with larger power flow requirement.

Desingh
RAjapalayam

Answer / kadher.304

mcb its thermal operated and use for short circit rating of
mcb 63amp(max)
mccb is thermal operated for over load current and magnetic
oprataion for instant trip in short circuit condition.rating
of 63amp(9min)

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