Which one is better for home wiring MCB or RCB
There are two types of electrical faults.
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Overcurrent. Or short circuit fault current.
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Earth fault current.
MCB (miniature circuit breaker) is the option for fuse. Fuse has to be replaced once it blow off, where as MCBs don’t have to replace if it trips. So the fault is identified by observing which circuit is faulty by seeing the tripped MCB. MCBs working principle is Thermal, Thermal-Magnetic. So it protects from over current and short circuit current.
RCCB (residual current circuit breaker) or RCD ( Residual current device )protects human from electrocution. When the circuit feeds the appliances, in the return the current flow in milliamperes which is sensed by RCCB. And RCCB / RCD trips instantly ( in 20 millisecond). The unbalanced current in the circuit / earth leakage current sensed by only RCCB or RCD.
So MCB does over current and short circuit protection.
Whereas RCCB/ RCD does only earth leakage protection.
RCBO is a combination of MCC and RCCB. So if you use RCBO then not required to use MCB