ISO 5474-1:2024

Overview

ISO 5474-1:2024 - "Electrically propelled road vehicles - Functional and safety requirements for power transfer between vehicle and external electric circuit - Part 1: General requirements for conductive power transfer" defines general safety and functional requirements for conductive power transfer between electrically propelled road vehicles (EVs) and external electric circuits. It applies to vehicle power supply circuits for voltages up to 1 000 V a.c. and 1 500 V d.c., and covers conductive charging modes 2, 3 and 4 (per IEC 61851-1) and reverse power transfer. External electric circuits themselves are not part of this standard.

Key topics and technical requirements

• Voltage coverage: Up to 1 000 V AC and up to 1 500 V DC for vehicle-side power circuits.
• Charging modes: Requirements for conductive charging in modes 2, 3 and 4; mode 1 excluded. For mode 4, requirements apply only when using isolated DC EV supply equipment per IEC 61851-23.
• Safety objectives: Protection against electric shock, thermal incidents, arc faults and unintended power transfer. Topics include insulation resistance, touch current limits, insulation coordination, protective conductor integrity and overcurrent/overload protection.
• Functional requirements: System architecture, EMC considerations, vehicle movement safety, and provisions for reverse power transfer (vehicle-to-grid or vehicle-to-home scenarios).
• Testing & verification: Test methods such as insulation resistance and protective conductor resistance measurements are specified.
• Information & marking: Requirements for owner’s manuals and vehicle/inlet markings to support safe use.
• Scope exclusions: Simultaneous operation of multiple EV plugs/vehicle inlets and power transfer while driving (electric road systems) are not addressed (under consideration). Mopeds/motorcycles are excluded (see ISO 18246). The standard is not a comprehensive maintenance/manufacturing safety manual.

Applications and who uses it

ISO 5474-1 is intended for:

• EV manufacturers and vehicle electrical system designers implementing vehicle inlets, connectors and internal power circuits.
• EV charging equipment and system integrators ensuring compatibility with vehicle-side requirements (especially for isolated DC charging equipment).
• Automotive safety and compliance teams preparing type approvals, conformity assessments and technical documentation.
• Standards writers, testing laboratories and certification bodies validating vehicle-side conductive charging safety and functional requirements.
• Engineers working on vehicle-to-grid (V2G) and reverse power transfer implementations where vehicle-side requirements are relevant.

Related standards

• IEC 61851-1, IEC 61851-23 (charging modes, DC supply equipment)
• IEC 62196 (plugs, vehicle connectors)
• ISO 6469-3 (electric vehicle electrical safety)
• ISO 18246 (mopeds and motorcycles)
• IEC 60664, IEC 60364-5-54, IEC 60479-2, ISO 20653

Keywords: ISO 5474-1, conductive power transfer, EV charging safety, reverse power transfer, electric vehicle standards, IEC 61851, vehicle power supply circuits.