Different faults, different protection
MCBs and MCCBs provide overcurrent protection. An RCCB detects residual-current imbalance but does not include overcurrent protection. An RCBO combines residual-current and overcurrent functions.
A rating is not a complete selection
AC or DC use, voltage, breaking capacity, trip characteristics and the required residual-current type matter. A device that physically fits in a board may still be unsuitable.
Make a useful enquiry
Send a nameplate photo and describe the circuit or application. Have a competent installer assess the complete protective arrangement; do not replace a tripping device with a higher rating to silence the symptom.
Further reading: Primary technical reference ↗
Apply this to your system
This guide explains concepts. Equipment selection and installation need an assessment of the actual system and the relevant manufacturer instructions.
Talk to an Engineer ↗