Electric Vehicle Conductive Charging System — General Requirements
IEC 61851-1:2017 is the foundational international standard for conductive charging of electric road vehicles, published by the International Electrotechnical Commission (IEC). It defines the four charging modes (Modes 1–4), the control pilot (CP) signalling between the electric vehicle supply equipment (EVSE) and the vehicle, safety requirements for the charging interface, and requirements for on-board and off-board charging equipment. The 2017 third edition updated control pilot duty cycle, current levels, and interoperability with ISO 15118 and IEC 62196. A Corrigendum 1 was issued in 2023.
Published by: International Electrotechnical Commission (IEC)
Current edition: IEC 61851-1:2017/COR1:2023 (3rd edition)
Replaces: IEC 61851-1:2010 (2nd edition)
Scope
IEC 61851-1 applies to on-board and off-board equipment for charging electric road vehicles at AC supply voltages up to 1,000 V and DC voltages up to 1,500 V. It defines the four EV charging modes:
- Mode 1: Slow AC charging via a standard household socket up to 16 A, without dedicated communication
- Mode 2: Slow AC charging via a household socket with an in-cable control and protection device (IC-CPD) — governed by IEC 62752
- Mode 3: Slow or fast AC charging via a dedicated EVSE with control pilot (CP) and proximity pilot (PP) signalling — the most common public and home charging mode
- Mode 4: DC fast charging via an off-board charger connected directly to the vehicle battery — governed by IEC 61851-23
- Control pilot (CP) signal: 1 kHz PWM duty cycle communicates available current and connection state between EVSE and vehicle
Relationship to other standards
IEC 61851-1 is the parent standard of the IEC 61851 family. IEC 61851-23 extends it for DC EV supply equipment (Mode 4). IEC 62196 defines the physical connectors used in Modes 2, 3 and 4. IEC 62752 defines the IC-CPD used in Mode 2. ISO 15118 provides the digital communication that overlays Mode 3 and Mode 4 charging sessions. IEC 63110-1 governs backend management of charging infrastructure. SAE J1772 is the North American equivalent for Mode 3 AC charging.
Disclaimer: This is not a definitive guide, just an indication and it is important that you always go back to the source for legislation.
References
- IEC 61851-1:2017 — Electric vehicle conductive charging system — Part 1: General requirements, IEC Webstore
See also: HV System — the pack-side electrical architecture that must interface with the charging modes and control-pilot signalling this standard defines. ISO 17409 covers the corresponding off-board charger safety requirements. IEC 62752 covers the in-cable protection device used for Mode 2 charging under this standard, and IEC 62840-2 covers the alternative battery-swap energy replenishment pathway.