e-Book: EV Service Equipment Personnel Protection Systems

Enhancing safety measures for personnel in electric vehicle charging operations

The electric vehicle (EV) market is rapidly expanding, making safety in EV infrastructure and equipment more critical than ever. Personnel protection systems within electric vehicle supply equipment (EVSE) are essential for safe operation. Certification of these systems is vital to protect users from potential hazards.

The importance of safety standards

EVSE acts as an intermediary between the utility grid and the EV and requires stringent safety measures. These systems, including EV charging stations, must provide a safe and efficient way to recharge EVs. Key components of EVSE include:

• EV couplers and cables for convenient connection.
• Conductive EV supply equipment to supply AC power.
• EV personnel protection systems to detect and mitigate shock hazards.

The most critical component, the personnel protection system, prevents electric shock, reduces fire risk, increases safety in wet environments and supports compliance with safety standards like UL 2231-1 and -2, the Standard for Personnel Protection Systems for EV Supply Circuits, Part 1: General Requirements for Personnel Protection, and Part 2: Specific Requirements for Protection Devices.

Safety requirements and standards

North American EVSE is evaluated using UL Standards, including UL 2594 and UL 2202, that cover electrical and mechanical safety to enhance EV operation and charging safety. These Standards mandate the certification of specific components, such as personnel protection systems, to protect users from electric shock.

• UL 2594, the Standard for Safety for Electric Vehicle Supply Equipment (EVSE)
• UL 2202, the Standard for DC Charging Equipment for Electric Vehicles (EVCE)

Understanding UL 2231

UL 2231-1 and UL 2231-2 are crucial for EV charging systems, focusing on the performance of EVSE components to meet safety requirements. It includes:

• Centrally grounded systems using charge current interrupting devices (CCIDs) for Level 1 and 2 EVSE.
• Isolated systems employing isolation monitor detection and interruption (IM/I) for high-power DC charging equipment.

Testing and compliance

Compliance with UL 2231-1 and UL 2231-2 involves rigorous testing of system reliability, including:

• Ground fault detection and interruption in line with Class A equation standards.
• Isolation monitor/initiator (IM/I) activation when isolation thresholds are exceeded.
• Auto-supervisory test circuit ensuring protective function before charging.
• Auto-reclosure feature allowing reattempts to initiate charging.

Benefits of certification

Certification of EVSE and personnel protection systems offers numerous benefits:

• Safety testing to evaluate compliance with safety standards.
• Demonstration of compliance with regulations and adherence to legal mandates and electrical codes.
• Assessing reliability and consistent performance.
• Helping to enhance consumer confidence and trust in EV charging infrastructure.
• Promoting innovation and improvement with advancements in charging technology.

To learn more about enhancing safety measures in electric vehicle charging operations, download our comprehensive guide. This resource provides in-depth information on safety requirements, testing and the benefits of certification for EVSE and personnel protection systems.