EVSE - What is EV Supply Equipment?
Feb 25, 2023
If you've heard of an "electric vehicle charging station," you may not know that it's actually an EVSE. EVSE stands for "electric vehicle supply equipment."
EVSE is a more precise and inclusive term, referring not just to the plug that charges your EV but also to the software, communications protocols, and other components that make it all work together.
What is EVSE?
The National Electronics Manufacturers Association (NEMA) defines EVSEs as devices that "provide electric power to the vehicle and use that to recharge the vehicle's batteries. EVSE systems include the electrical conductors, related equipment, software, and communications protocols that deliver energy efficiently and safely to the vehicle." This means that an EVSE is more than just a simple plug. It's a complex system with various components that work together to charge your EV safely and efficiently.
The three main components of an EVSE are software, enclosure, and plug. The software and communications protocols are responsible for ensuring that everything runs smoothly, while the enclosure houses the main relay, control module, and power supply.
The plug itself is often the most confusing part, as different types of connectors are used depending on the region and charging level. Some EVSE manufacturers build charging stations with a wide variety of connector types, and EV owners may need to carry adapters to ensure compatibility.
EVSEs don't actually charge your EV's battery, despite what their name suggests. Instead, they provide electric power to your vehicle, which charges the battery itself. The charging process is managed by the control module, which analyzes the connectors on the plug to ensure that everything is connected properly. Depending on whether you're using alternating current (AC) or direct current (DC) charging, the onboard charging system inside the EV may convert AC power to DC power before sending it to the battery.
To ensure interoperability and consistent quality, there are codes, rating systems, and standards that apply to both EVSEs and their installation infrastructure. These can include amperage requirements, quality control for grounding cables, and communications protocols to minimize friction during charging.
Although EVSEs have come a long way in the past few years, there's still room for improvement. The primary area for growth is speed, as even the best chargers can still take up to 30 minutes to fully charge an empty battery.
Continued innovation and development in EVSE technology will not only improve charging times but also make these devices more affordable for consumers. If EVs are to become the new standard, innovation can't just come from the cars themselves - it must also come from the devices and software that help charge them.