Three-phase supply

A three-phase supply is an electricity connection where the property is served by three live phases rather than one live phase and neutral. In GB low-voltage supplies, the standard declared voltage is 230 V between phase and neutral at the supply terminals, unless another arrangement has been agreed, while EV chargepoint specifications commonly refer to 400 V AC three-phase equipment. In home energy work, the phase arrangement matters because equipment such as solar inverters, batteries, EV chargepoints and heat pumps may be assessed against import capacity, export capacity, maximum demand, cut-out rating and per-phase limits.