EV Charging Installation Checklist Template

In the UK, the electrical wiring requirements for EV charging points are primarily based on the standards and regulations set forth in the British Standard 7671:2018 + A1:2020, which is also known as the IET Wiring Regulations 18th edition. Here are the requirements outlined in those regulations that must be integrated into the ev charging station checklist:

General Requirements

The IET provides two general areas that must be considered when selecting the voltage supply. Domestic areas can use a 240 V single-phase supply, while commercial sites can either use a 240 V single-phase or a 400 V three-phase supply. Supply frequency should be 50 Hz AC for both.

Dedicated Circuits

Each EV station must have its own dedicated circuit in its control panel. Cable sizing on these circuit boxes is dependent on the following: rated power, number of phases, expected voltage drop (3% is recommended), and continuous load factor. Inspectors conducting an installation assessment should verify these things to ensure compliance with regulations.

Earthing and Bonding

The Earthing arrangement for EV chargers depends entirely on the supply type. The PME (TN-C-S) supply requires two things. A protective bonding to the PME earth must be implemented, and open-PEN detection devices should be considered.

For TT supplies, the charger must adhere to earth-fault loop impedance limits, and a dedicated TT earth rod must be provided. All exposed metal parts of the charger—both PME and TT—should be grounded to the earth to prevent electric shock hazards.

Circuit Protection (MCB/Fuse)

When installing an MCB or fuse, it must match with the cable rating and operating current of the circuit. Derating factors must also be considered when selecting a circuit protection device, since EV chargers mainly function with a continuous load. For EV chargers operating on a three-phase supply, a dedicated protection device must be installed for each phase to obtain maximum protection and safety.

Residual Current Device Protection (RCD)

When installing an EV charging point, an RCD must be present. AC charging points should install a 30 mA type A RCD, while units that are capable of DC units should consider installing a Type B RCD. Typically, an RCD integrated with an MCB is recommended to protect the device from overcurrents and earth faults.

Routing Cables

Choosing the right cable depends entirely on the suitability of the area where the charger is installed. Charging units that are installed outside or exposed to outdoor conditions are recommended to use SWA, H07RN-F, and NYY types. However, installers must carefully select these cables, especially considering the frequent conditions they will encounter once installed. If cables are exposed to the possibility of mechanical damage, adequate protection devices on them must be provided.

Charger Location

The EV charging location also requires careful consideration. The area must be accessible to users and safe to operate. This means that chargers should be placed in areas free from direct water sources. If unavoidable, the charger must meet the IP54 ingress protection rating.
Furthermore, chargers should have enough clearance from walls, vehicles, and other obstructions to ensure safe use of the charger.