Reading an EV Charger Spec Sheet: What the Numbers and Terms Mean

An EV charger spec sheet covers power output, electrical supply requirements, connector types, and enclosure ratings. They’re also thick with insider terminology. What’s the difference between kW and kWh? Are single-phase and three-phase both available options for my location? How do I know whether to get a Type 1, Type 2, or NACS charging connector? And what do any of those words even mean? EV chargers are a significant purchase for a home and a serious infrastructure decision for a business, and it’s important to understand what you’re investing in and why before you buy. Here’s a quick rundown on some of the most important terminology you’re likely to see when looking through EV charger specs.

A kilowatt (kW) is a measurement of power, how fast the energy is being delivered or used. Conversely, a kilowatt-hour (kWh) is a unit of energy and is the amount of energy a 1 kW appliance uses when it runs for 1 hour. You can think of a kW as your speed - how fast a vehicle goes, and the kWh as the distance that vehicle travels. So, a 7 kW charger running for one hour delivers 7 kWh of energy, and driving 60 km/h for one hour covers 60 km of distance. AC Level 2 chargers typically come in 7.2 kW, 11 kW, and 22 kW models.

Power moves in waves. Single-phase power moves in a single wave and can deliver up to 7.2 kW. Three-phase power has three waves moving together, which is why three-phase chargers can deliver up to 22 kW of power. In the US, home power is nearly always single-phase because that’s how the American residential grid was built. And in Australia, residential supply is similarly single-phase in most homes, though three-phase is available on request in many areas. In Europe, however, homes often have three-phase power because those grids were developed later. American commercial buildings often have three-phase power as well. So when making purchasing decisions for an EV charger, make sure you know what kind of power you have before buying a charger. An electrician can confirm this for you during any standard site assessment.

For AC charging, there are three connector types you might hear about. First, there’s Type 1 connectors, also known as J1772. These are very common in the United States, while Type 2 connectors (Mennekes) are the standard for Europe and Australia. Finally, there’s the NACS (North American Charging Standard, originally developed by Tesla) connector. These are the standard connector for all Tesla vehicles and are becoming the de facto connector type in North America, although they are not standard in either Australia or Europe.

Level 2 charging stations come in cable and socket type. In North America, all charging stations are cable type, which means that the charging cable and connector are built into the station. This comes with both benefits and drawbacks. While it means that everything you need to charge is right there for you, it also means that the cable can more easily be damaged or vandalised. In other areas of the world, however, socket-type chargers are more prevalent. These charging stations have a socket in the face of the charger where the user can plug in one end of their charging cable and then plug the other end into the vehicle. The driver has a cable they keep in their car for times when they need to charge, and that cable belongs to them. The obvious drawback is that not all drivers will always have or remember the cable. Without it, a socket-type EV charger is useless.

Reading a spec sheet gets easier once you know what you're looking at. kW tells you how fast the charger delivers power. Single or three-phase tells you what your building can support. Connector type tells you whether the charger is compatible with your vehicle or market. And cable versus socket tells you how the charging session actually works for the person standing in the car park.

There's one more layer worth understanding before you buy or specify a charger: the IP and IK ratings that tell you how well the unit handles the physical environment it will be installed in. Dust, rain, pressure washing, and physical impact all get their own rating system, and knowing how to read them helps you choose a charger that will last in the conditions it will actually face. We cover those in another post: [LINK]

If you're ready to explore Level 2 charging options, take a look at the MSI Eco Series or get in touch with our team for a commercial quote.