Overview
IEC TS 61851-3-1:2023 is a Technical Specification in the IEC 61851 series that defines general rules and requirements for stationary DC EV supply equipment where protection against electric shock relies on double or reinforced insulation. It covers conductive transfer of electric power between the supply network and an electric road vehicle, a removable rechargeable energy storage system (RESS), or an on‑board RESS when connected to supply networks up to 480 V AC or 400 V DC with a rated output up to 120 V DC. The specification requires double/reinforced insulation between all AC and DC inputs and outputs.
Key topics and technical requirements
The document addresses practical and safety-focused aspects of DC EV supply equipment, including:
- Scope & classification
- Equipment types and EV supply system configuration (types A–F) and relation to ISO 18246.
- Voltages and currents
- Rated input/output voltage classes and current/voltage regulation expectations.
- Protection against electric shock
- Mandatory double/reinforced insulation rules, IP ratings, touch current limits, fault protection and handling of stored energy (capacitor discharge).
- DC leakage and Y capacitors
- Limits and treatment of DC leakage currents and EMI filter components.
- Communications
- Mandatory command-and-control communication and optional communication interfaces for control and telemetry.
- Constructional and performance tests
- Clearances and creepage, dielectric withstand (AC and impulse), insulation resistance, temperature rise, IP ingress protection, damp heat and mechanical tests.
- Accessories and cable assemblies
- Requirements for adaptors, latching devices, cable ratings, strain relief and storage for tethered cables.
- Safety systems
- Overload and short-circuit protection, optional emergency disconnects, and protection for built-in VCUs (AC/DC or DC/DC).
- Marking and documentation
- Installation and user manuals, marking durability and required identification of equipment types.
- Informative annexes
- Acoustical/optical signalling, socket-outlet positioning, conversion device considerations and example VCU wiring.
Applications and who uses it
IEC TS 61851-3-1:2023 is intended for:
- EV charging station manufacturers designing stationary DC EV supply equipment relying on insulated protection.
- Component suppliers (VCUs, cable assemblies, connectors) ensuring compliance with insulation and testing requirements.
- Test laboratories and conformity assessment bodies performing constructional and safety tests.
- System integrators, fleet operators, site owners and specifiers selecting or installing DC charging systems for public, commercial or private facilities.
- Regulators and safety inspectors referencing requirements for electrical safety and installation.
Keywords: IEC TS 61851-3-1:2023, DC EV supply equipment, conductive charging, double insulation, reinforced insulation, EV charging station, RESS, VCU, DC leakage currents.
Related standards
- IEC 61851 series (other parts covering AC/DC charging system requirements)
- ISO 18246 (corresponding type designations and interfaces)