If you are considering buying an electric vehicle—or even if you already have one—you may be considering adding some type of home charging equipment. However, the choices are not necessarily straightforward—especially if you aren’t an electrician or electrical engineer. Let’s take a look at what you need to know to make a smart choice. First, we’ll go over some basic terminology. Second, we’ll talk about your equipment choices, breaking that down into choices for Tesla owners and choices for owners of other EVs.
EV Equipment Terminology
Understanding a few key terms can make shopping for EV charging equipment less mysterious and enable you to have a more effective conversation with an electrician:
EV Chargers and EV Service Equipment. Industry insiders will tell you that all electric vehicles include an on-board charger. Vehicle manufacturers don’t let just anyone control the flow of energy into their batteries.
So what are these other boxes people want you to buy for your garage? Technically, they are called Electric Vehicle Supply Equipment, or EVSE. We won’t begrudge you for calling it a charger, though. What it does is make sure no power flows unless the charging plug is physically inserted into a vehicle, that the home does not deliver more energy than the vehicle can safely accept, and that the vehicle does not draw more than the home can safely provide.
120 Volt and 240 Volt circuits. Volts measure how hard electricity is pushing through a circuit. Almost all U.S. single family homes have 240V service, but most circuits use only half of this and thus operate at 120V. A few specialty circuits, such as those for electric dryers and ovens, operate at 240V.
Level 1 and Level 2. Level 1 EV service equipment operates at 120V. Level 2 equipment operates at 240V. As you might imagine, Level 2 equipment will charge your vehicle more quickly.
Amps. Amps measure electrical current—how much electricity is flowing. A 20A circuit can have up to 20A flowing through it, but typically has less at any given moment. The maximum amount of power a circuit can deliver is its voltage multiplied by its amperage.
All Level 2 equipment operates at 240V, but different models and configurations have different levels of maximum current. For example, one 240V charger may operate at a maximum of 32A and another at 48A. A 48A system will charge your vehicle more quickly than a 32A system if your vehicle is also designed to use that much current. An 48A system connected to a vehicle than can only draw 32A will not charge a battery more quickly.
SAE J1772 Connector. This is a standardized connector type used by all passenger EVs in the United States except Teslas. Any charger you buy from anyone but Tesla will have a J1772 connector for the vehicle. Teslas use a proprietary connector, but you can buy a small adapter from Tesla that will allow you to use a J1772 connector.
NEMA 5-15, 14-50, and 6-50 Receptacles. These are the official names of different types of outlets used in households. NEMA 5-15 is the name of the nearly universal 3-prong, 120V outlet. NEMA 6-50 and 14-50 two different 240V outlets. Most Level 2 chargers can be hardwired or connected via a 6-50 or 14-50 outlet.
NEMA 5-15 Receptacle
NEMA 6-50 Receptacle
NEMA 14-50 Receptacle
If You Have a Tesla
You’d think that because Tesla manufactures both vehicles and charging equipment, choosing charging equipment would be a no-brainer. However, you have to make sure you don’t get confused by their convoluted naming. We are here to help!
Gen 2 Mobile Connector. This is the solution that comes standard with all new Teslas. It includes a NEMA 5-15 adapter for standard 120V household outlets and puts out a maximum of 12A in this configuration. You could use the Gen 2 Mobile Connector like this without any help from Certasun. However, your vehicle would charge pretty slowly. (Likely days for a full charge.)
You can purchase a NEMA 6-50 or 14-50 adapter from Tesla at nominal cost to use the Gen 2 at 240V. In this configuration it will deliver 32A, but you’ll probably need someone like Certasun to install a 240V circuit.
Corded Mobile Connector. The Corded Mobile Connector operates at 240V and can deliver up up 40A, so it can charge most Teslas faster than the Gen 2 Mobile Connector. However, will not charge them as fast as a Wall Connector (see below). It comes with a NEMA 14-50 plug, so you’ll need an electrician to install a 240V circuit with that type of receptacle.
Wall Connector. The Wall Connector also operates at 240V but can deliver up to 48A, so it can charge most Teslas even faster than a Corded Mobile Connector. It can be hardwired or used with either of the 240V receptacles. The Wall Connector also has a feature that allows it to communicate with up to three other Wall Connectors to share a single circuit. (Charging will slow down when more than one vehicle is connected.)
The best solution for your home depends both on your vehicle and your needs. The Model 3 Standard Range can accept a maximum charge current of 32A, so none of these options will charge your vehicle any faster than the others, assuming you have a 240V circuit. You might choose the Wall Connector, though, if you want a cleaner, more durable, or more permanent solution, or if want to share a solution with another (higher-powered) Tesla. As of this writing, all Teslas except the Model 3 Standard Range can charge at up to 48A, so the Wall Connector will provide the fastest charging for those vehicles. You may decide, however, that one of the other options is fast enough for your needs.
If You Have Any Other EV
The options for other vehicles are, to some extent, more simple. Your vehicle almost certainly came with a 120V, Level 1 charger. This option might be totally acceptable as a complete solution if your car also has a gasoline engine. Such vehicles often have relatively small batteries, so it doesn’t take that much energy to recharge them. Besides, these cars can run on the gasoline engine alone if the battery isn’t charged.
If you have a fully battery-powered vehicle or you want to ensure a fast charge rate in a partial EV, however, you’ll want a 240V circuit and a Level 2 charger. We furnish Level 2 chargers from ClipperCreek that are durable, attractive, and made in the United States. Their HCS-40 should be able to recharge most vehicles from empty overnight. An HCS-60 would be a premium option for vehicles that can accept up to 48A of charging current. Both models can be configured to share a single circuit with another ClipperCreek charger.
What about web-enabled chargers that allow you to use your cellphone to monitor them and change settings? Frankly, we think these are unnecessary. Most EVs already have the ability to schedule their charging. We think most people are better served by a simple charging device that is easy-to-use and will operate reliably for a long time.
If you have any questions, please don’t hesitate to call us at (312) 638-0800.