A Residual Current Device (RCD) is a safety device designed to quickly disconnect electrical circuits when it detects an imbalance in the electric current, helping prevent electrical shocks and fire hazards. An RCD is a standalone device that is typically installed at the origin of the electrical installation. It offers protection to a group of circuits or to the entire installation, detecting imbalances in the current flow.
RCD’s & Split Load Consumer Units are now being phased out in place of RCBO’s, mainly due to the combination of earth leakage in modern installations & nuisance tripping. The cost of RCBO’s have come down considerably recently and benefit the installation by combining the functions of an RCD with an MCB into a miniature device. If a circuit trips when protected by an RCBO it does not affect half of the house / installation as it would with an RCD / split load consumer unit, only that individual circuit would be isolated.
