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Home EV Chargers and How to Choose One

charge-car-at-home Cars.com illustration by Paul Dolan

If you’re buying an electric vehicle, you’ll want to charge it at home, and if you’re being practical, that can mean only one thing: a Level 2 charging system, which is another way of saying it runs on 240 volts. Typically, the most range you can add with 120-volt charging, called Level 1, is 5 miles in one hour’s time, and that’s if the vehicle you’re charging is an efficient, small EV. That’s far from enough charging speed for a pure battery-electric vehicle that offers hundreds of miles of range. With the right car and Level 2 charging system, you can recharge at 40-plus miles of range per hour. Though a plug-in hybrid electric vehicle (PHEV) might get by with Level 1 because its battery is smaller, we still recommend Level 2’s speed to maximize EV driving. Level 1 charging doesn’t provide enough power to run the heat or air conditioning for preconditioning the cabin in extreme temperatures when still plugged into grid power.

Unless you’re buying a Tesla, a Ford Mustang Mach-E or another model that comes with a combination Level 1/2 mobile charger that travels with the car — or you want faster charging than those provide — you’ll need to buy one of your own that mounts to the wall or somewhere near where you park. Why do you need this added expense in the first place, and how do you choose one? Cars.com has purchased chargers from popular manufacturers, including ChargePoint, Electrify America, Wallbox, ClipperCreek and JuiceBox, for installation in editors’ homes, so we’ll tell you everything you need to look for.

Related: Electric Vehicles: Understanding the Terminology

What They Do: Compatibility and Safety

Just so you understand what you’re buying, it’s helpful to know what chargers do in the general sense. We call it a charger, but technically that’s the name reserved for the component onboard the car, out of sight, that makes sure a rechargeable battery gets the appropriate amount of power — more when it’s empty and at an optimal temperature, less when it’s closer to full or is exceptionally cold.

Level 1 and 2 hardware is actually something else, technically an EVSE, which stands for electric vehicle service equipment or supply equipment. EVSEs are relatively simple and designed to ensure safety and compatibility. The following information applies whether it has a Tesla connector at the end of the cable or the other universal pistol grip, which is named after the SAE International charging standard: J1772. The most basic EVSE encloses little more than a ground-fault circuit interrupter, some switching and circuitry that communicates the amount of power it can provide to an EV.

Roughly 240 volts is a lot to be holding in your hand, especially if you’re outside in the rain or snow. The EVSE, whether it’s at home or in public, won’t provide high voltage to the cable until the connector is attached to the EV. Once the connector is inserted, the car detects the EVSE’s pilot signal, which indicates how much power it can provide. Then charging can commence and the EVSE throws a switch, a heavy-duty relay called a contactor, which energizes the cable. You can usually hear this contactor click.

Similarly, if you go to remove a J1772 connector from an EV, the moment you press the release button, both the car and the EVSE will shut off charging so there’s no danger. (The same happens before a Tesla will release the charging connector.)

With the exception of the different connectors — Tesla and J1772, both of which can be adapted to work with the other for Level 1 and 2 charging — all chargers (to return to the casual name) follow the SAE J1772 standard that governs EV charging. This means any charger should charge any electric vehicle, and you don’t have to worry about the charger being too strong for your car even though some chargers have more power than some cars can exploit, as we detail in 5 Things That Could Slow Your EV’s Home Charging Speeds.

Chargers Are Universal

When it comes to choosing a Level 2 charger, your task isn’t difficult, at least not in the ways shoppers often assume. For example, chargers are universal because they all use the same charging standard, so you don’t have to buy a Volkswagen-branded charger if you buy a VW. (Tesla complicates this claim with its proprietary connector, but that’s one brand, and it’s about the connector alone.)

You also won’t find a particular charger brand that’s faster than another unless it’s backed up by the specifications, which we’ll get to.

Yet Chargers Can Be Quite Different

There are many brands and types of Level 2 chargers, and the difference that matters most is how much current they provide, but that explanation gets a bit thick, so we’ll start with the simpler differences:

Hardwired or Plug-In

Many EV owners have their chargers hardwired instead of plugged into a 240-volt outlet, meaning a more permanent and clean installation, and in some applications (like outdoors) and municipalities, it might be required. If you opt for a 48-amp or higher unit, this is the only option. But there are advantages to a charger that can plug into a 240-volt outlet. One is that it can be transported to any other location with a compatible outlet, and even if you never do this under normal circumstances, moving to a new house won’t require an electrician to free your property. It might also be helpful to have a 240-volt outlet in your garage for other purposes, such as a heater. Historically, in cases where the manufacturer has sold separate plug-in and hardwired versions of the same unit, the plug has added incremental cost, though JuiceBox seems to be bucking this with a slight upcharge for hardwired models, everything else being equal. The installation of an outlet rather than direct hardwiring may also add incremental cost. Our ChargePoint Home Flex, Electrify America HomeStation and Wallbox Pulsar Plus 40 all shipped with plugs accompanied by installation instructions to remove them if not needed. Our ClipperCreek HCS-50 and Enel X JuiceBox 32 are sold in two forms, and we purchased the plug-in HCS-50P and hardwired JuiceBox 32 along with a JuiceBox 48.

Networked or Not

A basic EVSE does what’s described above with no fanfare, as our ClipperCreek HCS-50P has done for years, but many now offer Wi-Fi connectivity so you can monitor, program or manually start or stop charging remotely via smartphone app. These products are often marketed as “smart chargers.” Some EVs duplicate these features, often with an app of their own, so paying extra for a networked charger might not be worthwhile — unless you’re interested in tracking the electricity used. Cars aren’t as likely to track their consumption while charging, and even if they do, they won’t necessarily account for all the power, including the losses associated with the charging process, as a networked charger can. Our networked chargers include all those mentioned above except the ClipperCreek.

We’ll be evaluating the pros and cons of these different networked products, their apps, partnerships (such as Amazon Alexa) and customer service in future coverage.

Length of Cable

For years, you could get a Level 2 charger with a cord less than 20 feet long — 12 and 18 were common — but now it seems the industry is settling on 25 feet as standard, or just trying to simplify things under crushing demand. There may still be options, especially if you consider a used unit. A longer cord is helpful if you can’t park close to the charger or have guests who need some juice and you don’t want to move cars around. Note that a vehicle’s charging port may be in front or back, depending on the model. You might also find that running the circuit to exactly where you want the charger isn’t possible or cost-effective, and a long charging cable can compensate for this.

All other things being equal, a longer cable will add incremental cost. If there’s a downside to the longer cord beyond cost, it’s probably just weight and manageability, which matters more if you get a plug-in charger and expect to transport it.

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Current Rating — That Other Level

We’re endlessly annoyed by the Level 2 distinction because it seems to represent one thing. Hardly. As we detail in What Is Level 1, 2, 3 Charging?, Level 2 represents voltage but not current, measured in amps, and both are factors that determine how quickly you can recharge an EV. We’ll use a couple Teslas to illustrate, merely because the company kindly provides this broad level of detail: At 12 amps a Level 2 charger will add 11 miles of range per hour of charging to a small Model 3 sedan, while a 48-amp charger will add 44 miles in the same period. Remember, both of these chargers are Level 2. The larger, less-efficient Tesla Model X SUV would add 5 miles and 30 miles using the same amp levels in an hour. See how Level 2 merely means better than Level 1 but doesn’t tell you the whole story?

If you’d prefer a non-Tesla example, Ford says a base Mustang Mach-E averages 20 miles of range per hour on a 240-volt outlet and 30 miles on its 240-volt, 48-amp Connected Charge Station. Don’t get the idea that a Tesla charger could charge the Mach-E faster than any other Level 2 unit — AC chargers all deliver their rated power. If one vehicle charges faster than another, it’s because the vehicle itself is more efficient, in which case the same amount of power over the same period translates to more miles of range.

ford-mach-e-charging Cars.com graphic by Paul Dolan and Joe Wiesenfelder

Choosing the Right Amp Rating

When choosing your charger’s fixed or adjustable amp rating (see next entry), you’ll want to know your car’s maximum charging rate in kilowatts, such as 10.5 kW to use the Mach-E as an example. Multiply that by 1,000 to get watts and you have 10,500 watts. Divide that by the 240 volts and, voila, you get 43.75 amps. That means a 48-amp charger would fill the Mach-E’s battery as quickly as possible, and a 40-amp maximum charger wouldn’t charge the Mach-E as fast as the car is capable. Yes, it should be simpler than this, but the industries involved haven’t caught on yet.

Remember that you can’t give an EV too much power, so don’t be afraid to go too high or future-proof your installation. Do be concerned about not having as much power as your EV can use if you can afford the required circuit.

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One Current Rating or Adjustable

All chargers have a maximum current rating, and many have that maximum alone, including our ClipperCreek and all JuiceBox residential chargers. But some chargers can be adjusted to work at a number of lower current levels to accommodate existing circuits. For example, a simple 48-amp charger can’t be used safely on a 40-amp circuit, but one that’s adjustable could be. This level of adjustability adds cost. Our ChargePoint, Electrify America and Wallbox units are adjustable, which might also explain why their manufacturers sell them with plugs that can be removed (rather than selling multiple versions, they make just one product for either mounting option and any circuit). Tesla’s Wall Connector is similarly adjustable with six selectable levels: 12, 16, 24, 32, 40 or 48 amps; the ChargePoint Home Flex’s six settings start at 16 amps and top out at 50; and the Wallbox Pulsar Plus 40 also has six settings but adds another at 20 amps: 16, 20, 24, 32, 40 and 48 amps. The Electrify America HomeStation — already our least favorite purchase on several grounds — has a 40-amp maximum and throttles down to only two other settings, 32 and 16 amps.

power-amperage-settings-screens-10-app-menu ChargePoint smartphone app adjustable current menus |

In addition to lower-rated circuits, chargers like these can be throttled down if their circuit is shared with another energy consumer, but it’s not advised. The charging standard calls for a dedicated circuit.

Don’t Confuse Charger and Circuit Ratings

If you want, say, 9.6 kW from your charger, you need a 40-amp Level 2 charger. That means you need a 50-amp circuit (meaning a 50-amp circuit breaker) because the breaker always has to meet roughly 125% of the continuous load regardless of the device involved. A 32-amp charger needs a 40-amp circuit, a 48-amp charger needs a 60-amp circuit, etc. Presumably an electrician wouldn’t make a mistake, but we’ve seen plenty of confusion already, especially when two of the most popular chargers nowadays are rated 32 amps (40-amp circuit) and 40 amps (50-amp circuit), both of which have a 40-amp spec associated. When it comes time to spend many hundreds of dollars on the hardware and installation, make sure you’re reading the right specification and getting the right thing. Some mistakes are easily reversed, while others are not.

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Outdoor Use

Most Level 2 chargers are rated for outdoor use, but we’ve found their ratings differ — both the standard cited, such as NEMA versus IP, which complicates comparisons (sort of like furnace filter ratings from one brand to the next) — and the degree of resistance to water, dust, snow, ice and such once you do cut through the ratings.

Sticking to Cars.com’s collection of mostly popular brands, the ChargePoint Home Flex and Electrify America HomeStation are rated NEMA 3R; the Wallbox Pulsar Plus and all ClipperCreek enclosures are rated NEMA 4; and the JuiceBox residential chargers are rated NEMA 4X, though that required some digging because all we found associated with JuiceBox products was “IP66.” These ratings are in increasing order of protection, which seems to give JuiceBox the advantage for outdoor installations, though the difference might not prove dramatic in actual use and depends partly on your climate.

Technically, NEMA 3R means it’s rated for outdoor use with protection from falling rain and ice formation, but not necessarily from driven rain. It’s not technically watertight or dust-tight. ChargePoint says the bottom of the Home Flex specifically is not sealed against intrusion. NEMA 4 is watertight with resistance to water directly from a garden hose or sprinkler. The X in the NEMA 4X represents additional corrosion resistance.

None of the manufacturers recommend pressure washing the units directly, though brief overspray from washing nearby surfaces such as a wall to which the charger is mounted is probably OK — though I’ll personally proceed with caution as the owner of a Home Flex rated NEMA 3R mounted to vinyl siding that requires seasonal cleaning. We also have JuiceBox chargers mounted outside on posts here in the Midwest, so if enclosures from either end of the rating spectrum fail over time, we’ll be able to share it with you.

As for extreme sunlight, such as what I’ve seen destroy countless plastic items in Arizona, the manufacturers include a degree of ultraviolet resistance to their products, but all recommend mounting their chargers in additional external enclosures for the most extreme climates — or at least overhead cover or shade, as full enclosures run the risk of trapping heat that’s best dissipated during charging.

Though it’s been more than a decade since Cars.com purchased its first home charging setup, most of the units mentioned above are relatively new, so we’ll be evaluating them over the coming months and years with the onslaught of new plug-in models and will report on how they perform and differ from each other.

home-charging-01-charging-station-spx Cars.com's first Level 2 EVSE | Cars.com photo by Joe Wiesenfelder

Cars.com’s Editorial department is your source for automotive news and reviews. In line with Cars.com’s long-standing ethics policy, editors and reviewers don’t accept gifts or free trips from automakers. The Editorial department is independent of Cars.com’s advertising, sales and sponsored content departments.

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