RCBO is a Residual Current Breaker with Overcurrent Protection (a type of electrical safety device that integrates leakage protection and overload/short circuit protection functions).
In simple terms, it is equivalent to combining “leakage circuit breaker (RCD)” and “miniature circuit breaker (MCB)” into one device and installing it in the same unit.
Core functions:
Leakage protection (RCD function):
When there is a leakage in the circuit (such as an electrical appliance having an exposed casing or someone getting an electric shock) and the current exceeds the set value (usually 30mA), the RCBO will automatically trip and cut off the power supply within an extremely short period of time (usually <0.1 seconds), preventing electric shock accidents and electrical fires.
Overload protection:
When the current in the circuit exceeds the rated value (for example, when too many electrical appliances are connected), the RCBO will trip like a regular air switch to prevent the wires from overheating and causing a fire.
Short circuit protection:
When the live wire and the neutral wire come into direct contact and generate a huge current, the RCBO will trip instantly to cut off the faulty circuit.
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