RELATED: Do I need a power supply upgrade for fleet charging?
The Core Safety Standards
BS 7671 Section 722 is the primary standard governing EV charging electrical installations in the UK. It sets requirements for circuit design, cable sizing, protective devices and earthing arrangements specifically for charging equipment.
Every EV charging circuit requires a dedicated Type A or Type B RCD rated at 30mA for personal protection. Type B RCDs are increasingly specified for DC capable chargers because they detect DC fault currents that Type A devices cannot. Each charger also needs overcurrent protection sized to the cable and charger rating.
The IET Code of Practice for Electric Vehicle Charging Equipment Installation provides practical guidance for applying BS 7671 to depot environments. It covers cable routing, distribution board design and protection coordination across multiple chargers.
Physical Installation Requirements
Outdoor depot chargers need IP65 protection against dust and water ingress as a minimum. IK10 impact resistance protects against vehicle contact and general depot activity. Chargers operating in covered but unheated areas still need IP55 rated enclosures.
Charging cables must not cross pedestrian or vehicle routes. The recommended maximum cable length is 7.5 metres between charger and vehicle connection point. Cable management systems keep everything tidy and off the ground.
Emergency isolation switches must be prominently labelled and accessible. In a depot with multiple chargers, isolation points should allow individual chargers to be disconnected without affecting the rest of the network.
RELATED: What is load balancing for EV charging?
Inspection and Certification
Every completed installation receives an Electrical Installation Certificate (EIC) confirming compliance with BS 7671. This is a legal requirement for new electrical work. The certificate covers circuit design, inspection results and test data.
Periodic inspection and testing should follow every 5 years for commercial installations, or annually for higher risk environments. We recommend annual visual inspections for depot chargers given the heavy use they receive.
All work must be carried out by qualified electricians. We are NAPIT accredited and all our engineers hold the relevant qualifications for EV charging installations. We handle the safety requirements so you do not have to interpret the standards yourself.
