IEC 62955:2018

Overview

IEC 62955:2018 specifies requirements and test methods for residual direct current detecting devices (RDC-DDs) utilized in AC charging stations for electric vehicles (EVs) under mode 3 charging configurations. These devices play a crucial role in increasing the safety of permanently connected charging infrastructure by detecting unwanted residual direct currents, in accordance with the provisions set out in IEC 61851-1 and IEC 60364-7-722. This standard applies to systems with rated voltages up to 440 V AC and frequencies of 50 Hz, 60 Hz, or both, with currents not exceeding 125 A.

Compliance with IEC 62955:2018 ensures that mode 3 EV charging stations are reliable and offer appropriate protection measures for users, vehicles, and infrastructure.

Key Topics

• Device Classification: IEC 62955 covers different RDC-DD configurations, including monitoring devices (RDC-MD) and protective devices (RDC-PD), subdivided by their construction, number of poles, connection style, and terminal types.
• Electrical and Mechanical Characteristics: Defines essential attributes such as rated voltage, current, frequency, operating and non-operating residual current levels, making and breaking capacities, impulse withstand voltage, and ambient conditions.
• Product Marking: Specifies the marking and information that must be supplied with the device for identification, safety, and operational guidance.
• Environmental and Installation Requirements: Describes normal operation and installation conditions, including pollution degree, temperature range, and site-specific environmental aspects.
• Construction and Safety Requirements: Mandates criteria for protection against electric shock, resistance to heat, fire, mechanical shock, and impact, as well as requirements for creepage and clearance distances.
• Testing and Verification: Outlines testing protocols to ensure correct and reliable device operation, including performance tests under normal and fault conditions, endurance, EMC compatibility, reliability, and marking indelibility.

Applications

IEC 62955:2018 is essential for manufacturers, installers, and operators of AC electric vehicle charging infrastructure, specifically in mode 3 charging stations. Key applications include:

• Electric Vehicle Charging Stations: Ensures that charging points provide reliable detection of hazardous residual direct currents, reducing the risk of electric shock or equipment damage.
• Infrastructure Safety Compliance: Supports adherence to international safety practices and electrical codes related to EV charging, particularly IEC 61851-1 and IEC 60364-7-722.
• Product Development and Certification: Serves as a technical basis for the design, testing, and certification of RDC-DDs, helping manufacturers produce compliant, high-quality devices.
• Retrofitting and Modernization: Provides guidance for upgrading existing installations to meet current safety standards, thereby improving the safety and reliability of legacy charging equipment.

Related Standards

• IEC 61851-1: Electric vehicle conductive charging system - Part 1: General requirements, defining the modes and safety principles for EV charging.
• IEC 60364-7-722: Low-voltage electrical installations - Part 7-722: Requirements for special installations or locations - supplies for electric vehicles.
• IEC 61008 and IEC 61009: Standards addressing general residual current devices (RCDs) for household and similar uses, which are important for understanding the relationship with RDC-DDs in EV charging.
• ISO 6469-3: Electric road vehicles - Safety specifications related to protection against electric shock in EV on-board and off-board components.

IEC 62955:2018 provides a critical framework for ensuring the safety and reliability of AC charging stations for electric vehicles, supporting the global transition toward e-mobility and sustainable infrastructure. Integrating this standard into product development and facility management fosters industry confidence and compliance across international markets.