MCB (MINIATURE CIRCUIT BREAKER)

• Rated current not more than 100 A.
• Trip characteristics normally not adjustable.
• Thermal or thermal-magnetic operation.

MCCB (MOULDED CASE CIRCUIT BREAKER)

• Rated current up to 1000 A.
• Trip current may be adjustable.
• Thermal or thermal-magnetic operation.

RCD (RESIDUAL CURRENT DEVICE / RCCB(RESIDUAL CURRENT CIRCUIT BREAKER)

• Phase (line) and Neutral both wires connected through RCD.
• It trips the circuit when there is earth fault current.
• The amount of current flows through the phase (line) should return through neutral .
• It detects by RCD. any mismatch between two currents flowing through phase and neutral detect by -RCD and trip the circuit within 30Miliseconed.
• If a house has an earth system connected to an earth rod and not the main incoming cable, then it must have all circuits protected by an RCD (because u mite not be able to get enough fault current to trip a MCB)
• RCDs are an extremely effective form of shock protection