A residual current operated circuit breaker with over-current protection, often abbreviated as RCBO, integrates both residual current protection (RCD) and over-current protection functionalities.

This device monitors for two main electrical faults:

  1. Residual Current Protection (RCD): It swiftly disconnects the circuit if it detects a leakage of current to the ground, protecting against electric shock.
  2. Over-current Protection: Similar to a miniature circuit breaker (MCB), it safeguards against excessive current flow due to overloads or short circuits. When the current surpasses a specified threshold, the over-current protection feature triggers, interrupting the circuit to prevent damage to the electrical system or appliances and reducing fire hazards.

The combination of these features makes an RCBO a versatile safety device, providing comprehensive protection against both ground faults and excessive current conditions in electrical circuits.