# The standards that govern V2L — a clause-indexed map

> A clause-by-clause map of the standards that govern EV V2L home backup — feature → standard → clause — with each entry's confidence flag. Standards are cited by reference only; no standard text is reproduced.

**Safety frame.** This is education, not an instruction to carry out work. Work connecting V2L equipment to fixed wiring is safety-critical and may be notifiable under Part P. It must be designed, installed, inspected and tested by a competent person to the current edition of BS 7671. Vehicle manufacturers generally do not sanction back-feeding fixed wiring from V2L outlets; follow manufacturer instructions.

## Still being verified (renders "Not confirmed")

- **(safety-critical)** What (if anything) BS 7671 Amendment 4:2026 changed for §722 / V2X / V2H / V2L / PME / open-PEN, and the “Chapter 57” number for the new stationary-battery chapter.
- BS EN IEC 60947-6-1:2026 UK adoption (IEC parent exists; no UK BSI adoption page located).
- ENA G98 / G99 Issue 2 exact clause/section locators (pending the official PDFs).
- BS 7430:2026 precise clause numbering (2026 edition < 1 month old at last check).

## Feature → standard → clause

- **EV charge-point earthing / open-PEN on a PME (TN-C-S) supply** — BS 7671:2018+A4:2026 `§722.411.4.1` — PME prohibition + protective-measure routes (confidence: inference)
- **Island-mode / backup source feeding the home** — BS 7671:2018+A4:2026 `§551 (esp. 551.4.3.2.1, 551.7)` (confidence: inference)
- **Floating V2L output → controlled re-earthing (indoors)** — BS 7671:2018+A4:2026 `§54 (542/544), separation §413 / §418.3` (confidence: inference)
- **TT island earth electrode (resistance Ra)** — BS 7430:2026 `with BS 7671 542.2.2 / 542.2.4` (confidence: inference) (deep dive: https://v2lworkshop.co.uk/standards/earth-electrodes-tt-island-bs-7430)
- **RCD type selection (Type A/F/B, smooth DC)** — BS 7671:2018+A4:2026 `§722.531` (confidence: inference)
- **Changeover / transfer switching (anti-paralleling)** — Switchgear & transfer-switching standards (BS EN 60947 / 60669) `60947-6-1 (ATS), 60947-4-1 (contactors), 60947-3 (isolators)` (confidence: inference) (deep dive: https://v2lworkshop.co.uk/standards/compliant-changeover-switchgear)
- **DNO notification (grid-parallel V2G/V2H)** — ENA EREC G98 / G99 (and G100) `G98 / G99 Issue 2; G100 export limitation` (confidence: inference)
- **Connector (Type 2 AC / CCS DC)** — BS EN IEC 62196 series `-2 (Type 2 AC), -3:2022 (DC/CCS)` (confidence: inference) (deep dive: https://v2lworkshop.co.uk/standards/connectors-and-comms)
- **Bidirectional comms (true V2G/V2H, not plain V2L)** — BS EN ISO 15118 series (key part -20:2022) `-20:2022 (bidirectional power transfer)` (confidence: inference) (deep dive: https://v2lworkshop.co.uk/standards/connectors-and-comms)
- **Inverter / power-converter safety** — BS EN 62109 series `-1 / -2` (confidence: inference) (deep dive: https://v2lworkshop.co.uk/standards/inverter-power-converter-safety)
- **Notifiable work / legal sign-off** — Approved Document P (Building Regulations, England) `Reg 12(6A) (England) + devolved equivalents` (confidence: verified)
- **Companion home battery (BESS) fire safety** — PAS 63100:2024 `PAS 63100:2024` (confidence: inference) (deep dive: https://v2lworkshop.co.uk/standards/pas-63100-home-battery-fire-safety)
- **Testing, verification & certification** — IET Guidance Notes (GN1–GN8) + On-Site Guide `GN3 + BS 7671 Part 6` (confidence: inference)

## The standards library

- **Requirements for Electrical Installations (IET Wiring Regulations, 18th Edition)** — BS 7671:2018+A4:2026. Governs every fixed-wiring aspect of a V2L home-backup arrangement: the PME/open-PEN earthing question, island-mode earthing, RCD selection, isolation and changeover. A car's standalone V2L socket sits outside §722 until its output is wired into the consumer unit. (edition checked 2026-06-14). Official source: https://electrical.theiet.org/bs-7671-18th-edition-wiring-regulations/about-bs-7671/.
- **IET Code of Practice for Electric Vehicle Charging Equipment Installation** — IET Code of Practice for EV Charging Equipment Installation, 5th Edition (2023). The 5th edition substantially expands bidirectional / “vehicle as storage” use cases, including island-mode operation — the core V2L home-backup scenario. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/iet-cop-ev-charging. Official source: https://shop.theiet.org/code-of-practice-for-electric-vehicle-charging-equipment-installation-5th-edition.
- **Electrical installations — Protection against fire of battery energy storage systems for use in dwellings — Specification** — PAS 63100:2024. The standard for any companion fixed home battery sitting alongside a V2L backup — location, fire detection, stored-energy limits, impact protection near vehicles. The vehicle-as-source side stays under BS 7671. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/pas-63100-home-battery-fire-safety. Official source: https://knowledge.bsigroup.com/products/electrical-installations-protection-against-fire-of-battery-energy-storage-systems-for-use-in-dwellings-specification.
- **Safety of transformers, reactors, power supply units and combinations — Part 2-4: isolating transformers (general applications)** — BS EN IEC 61558-2-4:2025 (isolating transformers). The indoor floating-output fix: a 61558-2-4-compliant isolating transformer breaks the galvanic link between the EV's floating V2L output and the house wiring, letting the secondary be re-earthed in a controlled way — restoring a normal earth-fault path and RCD operation while keeping the one PME/MET earth. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/isolation-transformers-indoor-v2l. Official source: https://knowledge.bsigroup.com/products/safety-of-transformers-reactors-power-supply-units-and-combinations-thereof-particular-requirements-and-tests-for-isolating-transformers-and-power-supply-units-incorporating-isolating-transformers-for-general-applications-1.
- **Protective earthing of electrical installations. Code of practice** — BS 7430:2026. The UK reference for designing and proving the local earth electrode that forms a TT-type island when a V2L output backs up a property — because the DNO/PME earth is normally isolated during backup. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/earth-electrodes-tt-island-bs-7430. Official source: https://knowledge.bsigroup.com/products/code-of-practice-for-protective-earthing-of-electrical-installations.
- **RCD/RCBO/MCB/RDC-DD product-standard register** — Protective-device product standards (RCD / RCBO / MCB / RDC-DD). A floating V2L output passes a socket tester but gives no RCD protection until bonded; and power-electronic sources can produce DC/higher-frequency residual currents a plain Type AC/A RCD may not clear. Device type selection (A/F/B + smooth-DC detection) is safety-load-bearing. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/rcd-types-for-v2l. Official source: https://knowledge.bsigroup.com/products/type-f-and-type-b-residual-current-operated-circuit-breakers-with-and-without-integral-overcurrent-protection-for-household-and-similar-uses-2.
- **BS EN 60947 / BS EN 60669 series — contactors, isolators, transfer switching** — Switchgear & transfer-switching standards (BS EN 60947 / 60669). The standards a designer points to when specifying the interlocked contactors, isolators and changeover/ATS, and the formal basis for insisting a V2L changeover is open-transition (break-before-make), never bridging grid and vehicle. (edition checked 2026-06-15). Deep dive: https://v2lworkshop.co.uk/standards/compliant-changeover-switchgear. Official source: https://knowledge.bsigroup.com/products/low-voltage-switchgear-and-controlgear-multiple-function-equipment-transfer-switching-equipment-3.
- **Plugs, socket-outlets, vehicle connectors and inlets — conductive charging of EVs** — BS EN IEC 62196 series. Defines the Type 2 interface almost all V2L on European-market EVs uses (a V2L adapter plugs into the car's Type 2 inlet). The connector geometry bounds how much backup power a V2L setup can deliver; the coupler is a live, latched interface — not an ordinary plug to be pulled live. (edition checked 2026-06-15). Deep dive: https://v2lworkshop.co.uk/standards/connectors-and-comms. Official source: https://knowledge.bsigroup.com/products/plugs-socket-outlets-vehicle-connectors-and-vehicle-inlets-conductive-charging-of-electric-vehicles-general-requirements-6.
- **Road vehicles — Vehicle-to-grid communication interface** — BS EN ISO 15118 series (key part -20:2022). Marks where V2L ends and true V2G/V2H begins: a vehicle's plain V2L socket does NOT use ISO 15118-20, but a future communicating bidirectional home charger feeding the consumer unit would. Don't imply V2L = ISO 15118. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/connectors-and-comms. Official source: https://knowledge.bsigroup.com/products/road-vehicles-vehicle-to-grid-communication-interface-2nd-generation-network-layer-and-application-layer-requirements.
- **Electric vehicle conductive charging system** — BS EN IEC 61851 series. Positions V2L correctly: a V2L adapter draws power OUT of the vehicle and sits outside the Mode 1–4 charging framework and the control-pilot path. The regulated grid-aware bidirectional pathway lives in the DC bidirectional work (-23/-24). (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/connectors-and-comms. Official source: https://knowledge.bsigroup.com/products/electric-vehicle-conductive-charging-system-general-requirements-5.
- **Safety of power converters for use in photovoltaic / battery / EV-derived power systems** — BS EN 62109 series. The standard most likely cited on a bidirectional EV charger/inverter or portable V2L unit's type-plate. Critically: a 62109 mark is NOT evidence of anti-islanding compliance — that duty lives in ENA G98/G99 and BS 7671, with islanding test methods in IEC 62116. (edition checked 2026-06-14). Deep dive: https://v2lworkshop.co.uk/standards/inverter-power-converter-safety. Official source: https://knowledge.bsigroup.com/products/safety-of-power-converters-for-use-in-photovoltaic-power-systems-particular-requirements-for-inverters.
- **Connection of generation/storage to the distribution network** — ENA EREC G98 / G99 (and G100). Marks the DNO-notification trigger. True islanded V2L — physically separated by a changeover so it cannot run in parallel or export — is generally outside G98/G99; but whether a given changeover genuinely prevents parallel operation is a design-and-test matter for the competent person and the DNO. (edition checked 2026-06-14). Official source: https://www.energynetworks.org/industry/connecting-to-the-networks/connecting-generation-to-the-electricity-networks.
- **Approved Document P — Electrical safety — Dwellings (2013 edition)** — Approved Document P (Building Regulations, England). A V2L arrangement that adds a dedicated inlet circuit, a changeover/transfer switch, or alters the consumer unit will normally be notifiable — the legal hook for the safety frame: design, install, test and certify by a registered competent person, not DIY. (edition checked 2026-06-15). Official source: https://www.gov.uk/government/publications/electrical-safety-approved-document-p.
- **IET Code of Practice for Electrical Energy Storage Systems (EESS)** — IET Code of Practice for Electrical Energy Storage Systems (3rd Edition). Relevant where a fixed home battery is paired with a V2L backup arrangement; the island-mode material is the analogue for a vehicle acting as a backup source. (edition checked 2026-06-14). Official source: https://electrical.theiet.org/guidance-and-codes-of-practice/.
- **Reciprocating internal combustion engine driven alternating current generating sets** — BS EN ISO 8528 series. An island-mode analogue: a V2L backup is a switched-alternative source like a standby genset, so the same changeover and earthing discipline applies (the source's earth reference must be correct in each switch state). (edition checked 2026-06-14). Official source: https://www.iso.org/standard/iso-8528.
- **IET Guidance Notes and On-Site Guide (companions to BS 7671)** — IET Guidance Notes (GN1–GN8) + On-Site Guide. GN3 (testing/verification) and GN8 (earthing/bonding) support the testing and sign-off, and the TT-island electrode design, for a V2L arrangement. (edition checked 2026-06-14). Official source: https://electrical.theiet.org/guidance-and-codes-of-practice/.

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_Last reviewed: 2026-06-15. Written against: BS 7671:2018 + A4:2026. Standards cited by clause only; not reproduced._