Changes to EV charger installation in the 2018 UK Wiring Regulations

EV charger installation – changes in the
2018 UK Wiring Regulations

The 18th Edition the UK Wiring Regulations, BS7671:2018, was released on 1st July and becomes mandatory from 1st Jan 2019. There are a number of important changes that affect EV charging – the main implications are as follows.

  1. Charging from a 13 amp socket outlet (Mode 2 charging)

    Mode 2 charging uses the charging cable with in-line control box usually supplied with the vehicle.

    Standard 13 amp socket outlets can no longer be used because they are not designed to supply a constant 10-13 amps as required by an electric vehicle. A new type of socket has been defined with uprated contacts and switches. This new socket type will be labelled at manufacture with the letters EV on the rear.

  2. Earthing

    It is critically important to provide a safe secure earth or alternative protection to each charging point and new, complex, more stringent rules have been introduced for the earthing of EV chargers.

    The mains electrical supply to any building will normally include an earth. The most common type of building earth cannot be used to earth an external EV charger unless certain conditions are satisfied.

    Often the solution is to earth the charger(s) with an earth spike but sometimes this too is impractical. 

    ElectrAssure will specify the safest and most cost effective means of earthing your EV  chargers that will conform to the new regulations.

  3. RCD Protection

    RCDs are now commonly installed on the socket and other circuits of fuse boards in homes and commercial premises to provide additional protection from fatal electric shock.

    However, the type of RCDs used on general circuits will not work correctly if used on electric vehicle charging circuits. Specialist types of RCD protection (Type B) must be used. There are different means of providing Type B protection, either in the charger itself or in the fuse board. Each option conforms to the new regulations but the difference in installation cost can be as much as £1000 per charger socket.

    ElectrAssure will specify a safe solution that conforms to the new regulations and is the most cost effective option for you.

Please note that these changes are not retrospective – they will only apply to new installations. Until 1st January the changes are optional but become mandatory for new installations on that date.

For more information please contact ElectrAssure.