Most domestic properties in the UK run on single-phase power — a 230V supply capable of delivering up to around 13kW. For a family home, that is plenty. But for a growing commercial unit, workshop, or factory, single-phase quickly becomes a bottleneck. Heavy machinery, CNC equipment, large compressors, commercial kitchens, and EV charging banks all demand more power than a single-phase supply can safely deliver.
Three-phase power solves this. Instead of one live wire, three-phase delivers three live wires carrying alternating current 120 degrees out of phase with each other. The result is a 400V supply that can deliver significantly more power — typically 30kW to 100kW or more, depending on your distribution board and fuse size. Motors run more efficiently, equipment starts under load more smoothly, and you can balance your electrical load across the three phases to avoid overloading any single circuit.
At DCC Electrics, we have installed three-phase supplies for manufacturing plants in Medway, workshop units in Dartford, and commercial kitchens in Maidstone. The process begins with a demand assessment: we calculate your existing and projected power requirements, then liaise with UK Power Networks to arrange a supply upgrade or new connection.
The physical installation involves a new three-phase meter, a larger distribution board with three-pole circuit breakers, and often a new main earthing and bonding system. Cable sizing is critical — three-phase cables must be rated for the full balanced load, and the protective devices must be coordinated so a fault on one phase does not cascade into the others.
Many businesses do not realise they already have a three-phase supply but are only using one phase. We have helped several clients unlock their existing capacity simply by rewiring their distribution board and balancing loads correctly. In other cases, a new dedicated three-phase sub-board for a specific machine — a CNC router, a powder coating oven, or a car lift — is the most cost-effective solution.
If your circuit breaker trips every time you start a heavy machine, or your energy supplier has flagged that you are approaching your supply limit, it is time to talk about three-phase. Our engineers provide free site assessments and can guide you through the entire process from planning to certification.
