Electrical Systems in London, domestic properties
The Fuse Box or Consumer Unit
The fuse box is the house or flat’s insurance against electrical fires and safety against electrical shocks. If an electrical circuit is made to carry more current than it was designed for, perhaps by running a heater from a lighting power point, the fuse for that circuit will overheat and melt if the Fuse Box is the old style or the modern fuse will be cutting off the current to the electrical circuit.
If an old fuse is replaced by heavier wire, instead of the fuse melting, it is the cables, out of sight, under the floor boards, inside the walls and ceilings, against wooden joists and timber that will overheat and melt. This can start a fire and fires started this way are not covered by the Insurance Policy. Upgrade your electrical system to be safe using a qualified electrician.
Circuit Breakers are switches that turn off when overloading by current. They can be reset.
Old fuses are thin wires designed as weak links in electrical circuits. In even older electrical circuits, there are usually two fuses, one for live wire and one for neutral. The standard for old electrical systems is just one fuse fitted to the live wire. Old fuses melt when overloaded, slowly with a small overload or with a big noise ( bang ) if for example two bare wires touch. ( Live & Neutral, etc )
Modern fuses called MCB (Micro Circuit Breaker) are designed with safety and practicability in mind. They detect when a circuit is overloaded with precision and trips the electrical circuit. They are very easy to reset.
Modern Fuse Boxes – Consumer Units are protected by RCD system (Residual Current Device) for domestic buildings and RCBO ( Residual Current Breaker with Overload Protection ) for commercial – industrial buildings.
RCDs are designed to trip (shutdown) the electrical circuit if there it detects an imbalance in the electrical system, making the electrical system even safer.