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UL's EV standards development activities

CHARGING STATION AHEAD UL is the key North American developer of safety-related EV Standards. We also actively cooperate with other standards developing organizations in sharing our EV safety expertise. A few of our contributions to EV safety standards include:

UL Standards

Standard for Safety, Electric Vehicle (EV) Charging System Equipment, UL 2202

This Standard covers conductive and inductive charging system equipment intended to be supplied by a branch circuit of 600 volts or less for recharging the storage batteries in over-the-road EVs. In an inductive charging system, there is no direct metal-to-metal electrical connection between the charger and the vehicle. Instead, electrical power is passed through an electromagnetic field between the primary winding of a transformer, which is usually located off board the vehicle, to the secondary winding of the transformer which is usually located on board the vehicle. Conversely, in a conductive charging system, power is passed from the charger to the vehicle though direct metal-to-metal contact by way of a coupler or a plug and receptacle suitable for EV charging.

Standard for Safety, Personnel Protection Systems for EV Supply Circuits, UL 2231

This Standard covers devices and systems intended for use in accordance with the National Electrical Code ® (American National Standards Institute/National Fire Protection Association 70), to reduce the risk of electric shock to the user from accessible parts, in grounded or isolated circuits for charging EVs.

Standard for Safety, Plugs, Receptacles, and Couplers for EVs, UL 2251

This Standard covers plugs, receptacles, vehicle inlets, and connectors rated up to 800 amperes and up to 600 volts ac or dc, intended for conductive connection systems, for use with EVs in accordance with the National Electrical Code ® for either indoor or outdoor nonhazardous locations.

Other Codes and Practices

SAE J1718, Recommended Practice for Measurement of Hydrogen Gas Emissions from Battery-Powered Passenger Cars and Light Trucks During Battery Charging

Research at UL developed data and information that aided in the development of the hydrogen emission testing procedure in the Recommended Practice. This Recommended Practice describes a procedure for measuring gaseous hydrogen emissions from the aqueous battery system of battery-powered passenger cars and light trucks. The purpose of the procedure is to determine what concentrations of hydrogen gas an EV, together with its charger, will generate, and whether or not forced air ventilation is required when a particular EV and its associated battery and charging system are used in a residential garage.

Research at UL developed data and information on EV charging systems with respect to hydrogen gas emissions and ventilation requirements that aided in the development of the National Electrical Code ® (1996 edition), Article 625 -- Electric Vehicle Charging System Equipment. The article covers electrical conductors and equipment external to an EV that connect an EV to a supply of electricity by conductive or inductive means, and the installation of equipment and devices related to EV charging.

For more information about UL's electric vehicle activities, please contact Peter Boden at UL's Northbrook office at +1-847-272-8800, ext. 42011.

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