The consumer unit — commonly called the fuse box — is the nerve centre of your home's electrical installation. It receives the electricity supply from the meter, divides it into individual circuits, and provides protection for each circuit via a circuit breaker or fuse. Understanding what it does helps you make informed decisions about whether yours needs upgrading.
Modern consumer units must comply with BS 7671 (the IET Wiring Regulations, 18th Edition) and the Wiring Regulations Amendment 1:2020. They contain two key types of protective device: Miniature Circuit Breakers (MCBs), which protect against overcurrent and short circuits, and Residual Current Devices (RCDs), which protect against electric shock by detecting leakage currents as small as 30mA. Current regulations require consumer units to have either a split-load arrangement (with two RCDs protecting different groups of circuits) or RCBO protection on every circuit.
Consumer units also need to be housed in non-combustible enclosures — metal consumer units have been required in domestic premises since the 2016 amendment to the wiring regulations. If your unit is in a plastic enclosure, it does not comply with current standards. This alone is not a legal defect if the installation was compliant when it was installed, but it is a factor to consider. Similarly, old-style fuse boards with rewirable fuses are not illegal, but they offer much less protection than a modern unit.
When DP Power Solutions carries out a consumer unit upgrade, we disconnect the existing unit, install the new metal-clad consumer unit with the correct protective devices for your installation, reconnect all circuits, and carry out a series of tests to confirm the installation is safe and compliant. We then issue a full Electrical Installation Certificate and notify the work to the local authority under Part P of the Building Regulations. The job typically takes one day and the supply is off for a few hours during the changeover.
About DP Power Solutions: We are qualified domestic electricians based in Staffordshire, providing EICRs, consumer unit upgrades, rewires, EV charger installation, and more across Cannock, Rugeley, Lichfield, Stafford, and the surrounding area.