Create EV Charger Certificates on Your Phone

An EV charger installation certificate is the Electrical Installation Certificate required by BS 7671 Section 722 after every dedicated EV charging point installation.

Specifically, it is the EIC produced after installing a dedicated electric vehicle charging point, certifying that the installation has been designed, constructed, inspected, and tested in accordance with BS 7671:2018+A4:2026 (the IET Wiring Regulations, 18th Edition), with particular attention to the requirements of Section 722, which deals specifically with the supply of electric vehicles.

The certificate is a legal document. It confirms to the property owner, the Distribution Network Operator (DNO), and any competent person scheme provider that the EV charging installation meets the required safety standards. Without a valid EIC, the installation cannot be signed off through a competent person scheme, and the property owner may not be able to claim any available government grants or meet their insurance obligations.

Unlike a standard domestic circuit installation, an EV charger certificate must address several additional considerations specific to Section 722. These include the earthing arrangement assessment (particularly for PME supplies), load management provisions, the type of charging mode, cable sizing for continuous duty at maximum load, and the selection of appropriate protective devices. The certificate must demonstrate that all of these requirements have been properly assessed and met. The underlying Electrical Installation Certificate form is the basis for EV charger certification.

Elec-Mate provides a purpose-built EV charger certificate form that includes all Section 722 requirements as structured checklist items. Rather than trying to remember every regulation, the app guides you through each requirement, validates your test results, and produces a professional PDF certificate ready to issue on site.

Section 722 of BS 7671:2018+A4:2026 sets out the particular requirements for the supply of electric vehicles. It applies to circuits intended to supply electric vehicles, including those for charging at residential properties, workplaces, and public charging locations. Understanding these requirements is essential for every electrician installing EV chargers.

The section covers several critical areas. Regulation 722.411.4.1 addresses the earthing arrangements where the supply is TN-C-S (PME). Because an open PEN conductor fault could place a dangerous potential on the vehicle body via the charging cable, the regulation prohibits using the PME earthing facility for the protective conductor contact of an outdoor charging point unless one of the permitted alternative methods is used. This is one of the most important and most commonly misunderstood requirements in EV charger installation.

The circuit must be designed for continuous duty — the cable and protective device must be rated for the full load current drawn continuously. For a standard 7kW domestic charger, this means a 32A circuit with no diversity applied. Under Regulation 722.312.2.1, a circuit supplying EV charging equipment in a TN system shall not include a PEN conductor. Regulation 722.531.3.101 governs the selection of the RCD and the detection of DC fault current for the charging circuit.

The circuit must have 30mA RCD additional protection in line with Regulation 415.1. The type of RCD depends on the charger: where the charging equipment does not itself provide protection against DC fault current, Regulation 722.531.3.101 requires a Type B RCD, or a Type A RCD combined with a residual direct current detecting device (RDC-DD to BS IEC 62955) that disconnects on a smooth DC residual current of 6mA or above. Always check the charger manufacturer installation instructions.

Note: where the protective measure of electrical separation is used (Regulation 722.413.1.2), it is limited to the supply of one electric vehicle from one unearthed source through a fixed isolating transformer. AFDDs are not required for circuits supplying EV charging equipment conforming to the BS EN 61851 series that incorporate socket-outlets or vehicle connectors to BS EN IEC 62196-2 (Regulation 722.421.1.7.201).

The majority of domestic properties in the UK are supplied with a TN-C-S (PME) earthing system. Under Regulation 722.411.4.1, where an EV charger is installed on a PME supply, a PME earthing facility must not be used as the means of earthing for the protective conductor contact of a charging point located outdoors (or one that might reasonably be expected to charge a vehicle outdoors) unless one of the permitted alternative methods applies. The most common method is to install a separate installation earth electrode for the EV circuit, effectively creating a TT earthing arrangement for that circuit alone. (Indent (a) of this regulation was deleted by BS 7671:2018+A2:2022, and the A4:2026 amendment adds a further alternative method.)

The reason for this requirement is safety. On a PME supply, the neutral and earth are combined in the supply cable (the PEN conductor). If the PEN conductor becomes disconnected (an open PEN fault), the voltage on the PME earth terminal can rise to a dangerous level. Because an EV charging cable provides a direct metallic connection between the installation earth and the vehicle chassis, a person touching the vehicle during an open PEN fault could receive a lethal electric shock. By using a separate TT earth electrode for the EV circuit, this risk is eliminated because the vehicle earth is independent of the PME system.

Installing the earth electrode requires driving a copper-clad earth rod into the ground, typically to a depth of 1.2 to 2.4 metres. The earth electrode resistance (Ra) must be measured and recorded. Combined with the 30mA RCD, the product of Ra and the RCD operating current must not exceed 50V (i.e., Ra must be less than approximately 1667 ohms for a 30mA RCD, though in practice a much lower value is desirable for reliable operation).

There are some exceptions. If the property already has a TN-S earthing system (where the earth is provided by the cable sheath), or if it has an existing TT system, the separate earth electrode for the EV circuit may not be required — though the 30mA RCD protection is still mandatory. Some newer chargers with built-in earth monitoring may offer alternative protective measures, but the installer must always follow the specific requirements in BS 7671 and the charger manufacturer instructions.

Before installing an EV charger, the installer must consider the impact on the property's maximum demand and whether notification to the Distribution Network Operator (DNO) is required. A standard 7kW single-phase EV charger draws 32A continuously, which is a significant addition to a typical domestic supply.

Most domestic properties have a supply fuse rated at 60A, 80A, or 100A. If the existing maximum demand of the property (including electric showers, cookers, immersion heaters, and other large loads) plus the 32A EV charger exceeds the supply fuse rating, action is needed. This might involve installing a load management device that limits the charger output when other loads are active, or it might require requesting a supply upgrade from the DNO.

DNO notification is generally required when connecting a load of 13.8kVA (approximately 60A single phase) or above, or when the total demand of the property will exceed the existing supply capacity. In practice, most DNOs ask to be notified of all EV charger installations through their online portals. This notification helps the DNO manage the local network and plan for the increasing demand from electric vehicles across the grid.

Elec-Mate includes a maximum demand calculator within the EV charger certificate. You enter the existing loads on the supply, and the app calculates the total demand including the new charger. If the total exceeds the supply fuse rating, the app prompts you to document the load management solution and record the DNO notification reference number.

Load management is increasingly important as more EV chargers are installed on the UK electrical network. A CT (current transformer) clamp is typically installed on the supply tails to monitor the total current drawn by the property in real time. The charger uses this data to dynamically adjust its charging rate, reducing the output when other loads are active and increasing it when demand is low.

This dynamic load balancing ensures the supply fuse is never overloaded, even when an electric shower and an EV charger are both running simultaneously. It eliminates the need for a supply upgrade in many installations and is a cost-effective solution for properties with limited supply capacity.

Smart charging goes further than simple load management. Under the Electric Vehicles (Smart Charge Points) Regulations 2021, all new domestic and workplace EV chargers must be "smart" by default. This means they must be capable of being remotely controlled, must default to off-peak charging times, and must respond to signals from the electricity network to help balance supply and demand.

From an installation certificate perspective, the load management and smart charging configuration must be documented. The certificate should record whether a CT clamp has been installed, the maximum current limit set by the load management device, and the smart charging settings configured during commissioning. Elec-Mate provides dedicated fields for all of this documentation.

Regulation 722.311.201 (A4:2026) explicitly permits load curtailment — including automatic or manual load reduction or disconnection — to be taken into account when determining the maximum demand of the installation or any part thereof. This means a properly documented CT-clamp load management system can legitimately reduce the assessed maximum demand, potentially avoiding the need for a supply upgrade or DNO capacity increase.

Every Mode 3 EV charger must be supplied by its own dedicated circuit from the distribution board. The circuit must be designed for continuous duty at the full rated current of the charger. For a standard 7kW domestic charger, this means a 32A circuit with no diversity applied — the cable, protective device, and all connections must be rated for 32A drawn continuously for extended periods.

The protective device should be a 32A Type A RCBO for most domestic installations. The Type A characteristic provides protection against both AC and pulsating DC fault currents, which is appropriate for Mode 3 chargers with built-in DC residual current detection. If the charger does not include DC detection, a Type B RCBO may be required — always check the manufacturer instructions.

Cable sizing for a 32A continuous load requires careful consideration of all derating factors. The minimum cable size for a typical domestic installation is 6mm² twin-and-earth (for thermoplastic insulated cable clipped direct). However, this assumes favourable conditions: ambient temperature not exceeding 30 degrees Celsius, no grouping with other cables, and a circuit length short enough to keep the voltage drop within the 5% limit (11.5V on a 230V supply).

For longer cable runs — common when the charger is mounted on an external wall or in a detached garage — a larger conductor may be required to meet the voltage drop requirement. For external underground runs, SWA (steel wire armoured) cable is typically used and must be buried at the correct depth as specified by the installation design. The SWA armour can be used as the circuit protective conductor (CPC) but must be properly terminated with gland plates and earth tags. The table below gives indicative starting points; always calculate each circuit for its actual conditions.

The UK government has offered various grant schemes to support the uptake of electric vehicles, including grants towards the cost of installing domestic and workplace EV chargers. The Office for Zero Emission Vehicles (OZEV) historically administered the Electric Vehicle Homecharge Scheme (EVHS) and the Workplace Charging Scheme (WCS). While the specific schemes available may change over time, the documentation requirements remain broadly similar.

To claim a grant, installers typically need to submit the completed Electrical Installation Certificate, photographs of the installed charger, evidence of the DNO notification, and confirmation that the installation meets all Building Regulations and BS 7671 requirements. The certificate must demonstrate compliance with Section 722, including the earthing assessment and load management provisions. Incomplete or incorrect documentation is one of the most common reasons for grant claims being rejected.

Elec-Mate streamlines this process by producing a certificate that includes all the documentation typically required for grant submissions. The Section 722 checklist, PME assessment, load management details, and test results are all structured in the format that scheme providers and grant bodies expect, reducing the risk of rejection due to missing information.