An RCBO (Residual Current Circuit Breaker with Overcurrent Protection) is an electrical safety device that combines two functions into a single device: residual current protection and overcurrent protection.
Residual current protection detects any imbalance in the electrical circuit caused by a fault or leakage to earth, and quickly interrupts the circuit to prevent electrical shock or electrocution.
Overcurrent protection, on the other hand, detects and protects against excess current caused by a short circuit or overload.
By combining these two functions, an RCBO provides an additional layer of protection against electrical hazards, and is commonly used in residential, commercial and industrial electrical installations.