Product Update: I originally
posted a JuiceBox review here on June 14th 2015. Since then, eMotorWerks
has made improvements and is positioned as a leader in the home charging
industry. I felt it was time to update the post.
One of the first things many
first-time electric car owners ask once they've bought (or are about to buy)
their new car is what home charging solution should they choose. In fact, other
than asking for advice on specific plug-in cars, it's the most popular question
I get from readers.
Luckily, there are some really good choices on the market now, and the prices for home EVSEs are considerably less than they were when I first started driving electric in 2009. Back then, the only level 2 home EVSEs that I would recommend were from Clipper Creek. Clipper Creek still makes very good products, and I still recommend them, but the competition is getting better all of the time, and one company in particular, eMotorWerks has rapidly climbing to the top of home EV charging market.
Before I get into the review, I'd first like to explain some basic EV charging levels and terminology. This applies to charging in North America, as electric supply is different for most European countries.
EVSE: Electric Vehicle Supply Equipment. These are quite often called "chargers" or "charging stations." That really isn't the correct terminology though, because they don't actually charge the car. They really just supply the electricity safely, from the power source to the vehicle. The actual charging equipment is built into the electric cars. Some EVSEs are portable, while others are hard wired and permanently installed.
Level 1: Every electric car sold or leased in the US that isn't a Tesla comes with a Level 1 portable EVSE. Some manufacturers, like BMW, call it an "occasional use charger." Level 1 EVSEs can be plugged into a simple 120-volt household outlet and typically charge at 6, 8 or 12 amps. Tesla doesn't bother supplying their customers with a basic Level 1, 120-volt EVSE, because their vehicles have such large batteries that they would take very long to slow-charge on 120 volts. For that reason, every Tesla comes standard with a portable 240-volt EVSE for more robust charging at home or on the road.
Level 2: Level 2 EVSEs charge at 240 volts and most of the time are permanently installed in a garage or public parking lot. However, recently some manufacturers have been selling portable 240-volt EVSEs, allowing the owner the flexibility of using the equipment at home as well as on the road, provided they can find a 240 volt outlet that they can plug into. The JuiceBox Pro 40 which I'll be reviewing here today is one of the few EVSEs that comes with a NEMA 14-50 plug option, instead of requiring the owner to hard wire it to their home. I think it’s important to give the customer the choice to decide if they want a hard-wired, or portable EVSE. For that reason, I hope that all EVSE manufacturers decide to give the customer both options.
DCQC / DCFC: DC Quick Charge or DC Fast Charge. DC fast charge allows rapid charging of electric vehicles, enabling long distance travel with little inconvenience. DC Quick Charge stations can charge many EVs up to 80% full in about 30 minutes, but are not something an individual would buy for home use because of the cost and required 480 volt electric supply. These units are very expensive and are only just beginning to really proliferate. Unlike Level 1 and 2 charging, there are multiple connectors used by different manufacturers, as a single standard hasn't been established yet.
Some people live fine with their EV charging solely with the supplied 120-volt portable EVSE. However, most owners will prefer using a 240-volt EVSE, so that they can charge much faster, enabling the vehicle to be driven more miles if needed. For example, a basic 120-volt EVSE will replenish about 4 to 5 miles of range per hour. A standard 30-amp 240-volt Level 2 EVSE will add 20 to 30 miles of range per hour to the typical EV. That can make the difference of being able to use the car or not on some days.
Luckily, there are some really good choices on the market now, and the prices for home EVSEs are considerably less than they were when I first started driving electric in 2009. Back then, the only level 2 home EVSEs that I would recommend were from Clipper Creek. Clipper Creek still makes very good products, and I still recommend them, but the competition is getting better all of the time, and one company in particular, eMotorWerks has rapidly climbing to the top of home EV charging market.
Before I get into the review, I'd first like to explain some basic EV charging levels and terminology. This applies to charging in North America, as electric supply is different for most European countries.
EVSE: Electric Vehicle Supply Equipment. These are quite often called "chargers" or "charging stations." That really isn't the correct terminology though, because they don't actually charge the car. They really just supply the electricity safely, from the power source to the vehicle. The actual charging equipment is built into the electric cars. Some EVSEs are portable, while others are hard wired and permanently installed.
Level 1: Every electric car sold or leased in the US that isn't a Tesla comes with a Level 1 portable EVSE. Some manufacturers, like BMW, call it an "occasional use charger." Level 1 EVSEs can be plugged into a simple 120-volt household outlet and typically charge at 6, 8 or 12 amps. Tesla doesn't bother supplying their customers with a basic Level 1, 120-volt EVSE, because their vehicles have such large batteries that they would take very long to slow-charge on 120 volts. For that reason, every Tesla comes standard with a portable 240-volt EVSE for more robust charging at home or on the road.
Level 2: Level 2 EVSEs charge at 240 volts and most of the time are permanently installed in a garage or public parking lot. However, recently some manufacturers have been selling portable 240-volt EVSEs, allowing the owner the flexibility of using the equipment at home as well as on the road, provided they can find a 240 volt outlet that they can plug into. The JuiceBox Pro 40 which I'll be reviewing here today is one of the few EVSEs that comes with a NEMA 14-50 plug option, instead of requiring the owner to hard wire it to their home. I think it’s important to give the customer the choice to decide if they want a hard-wired, or portable EVSE. For that reason, I hope that all EVSE manufacturers decide to give the customer both options.
DCQC / DCFC: DC Quick Charge or DC Fast Charge. DC fast charge allows rapid charging of electric vehicles, enabling long distance travel with little inconvenience. DC Quick Charge stations can charge many EVs up to 80% full in about 30 minutes, but are not something an individual would buy for home use because of the cost and required 480 volt electric supply. These units are very expensive and are only just beginning to really proliferate. Unlike Level 1 and 2 charging, there are multiple connectors used by different manufacturers, as a single standard hasn't been established yet.
Some people live fine with their EV charging solely with the supplied 120-volt portable EVSE. However, most owners will prefer using a 240-volt EVSE, so that they can charge much faster, enabling the vehicle to be driven more miles if needed. For example, a basic 120-volt EVSE will replenish about 4 to 5 miles of range per hour. A standard 30-amp 240-volt Level 2 EVSE will add 20 to 30 miles of range per hour to the typical EV. That can make the difference of being able to use the car or not on some days.
I've charged my EVs on
pretty much every brand of EVSE on the market today, and I have a host of different
EVSEs in the garage at my house, which I use for various testing and when I
have multiple visitors that also have cars that plug in. This gives me an
opportunity to really compare the units side by side.
When I did my JuiceBox review in 2015,
eMotorWerks was still a very new company, and had just announced that they had
recently sold their 3,500th JuiceBox. Less than three years later,
they have sold close to 30,000 EVSEs, and were recently acquired
by Enel, a multinational power company, and one of Europe’s largest Utilities.
Also, at the time of that review, eMotorWerks hadn’t yet received UL safety
certification for the JuiceBox Pro 40, and they now have that certification.
First, I'd like to point out the JuiceBox Pro 40 can deliver up to 40 amps of power. The vast majority of Level 2 EVSEs currently on the market are limited to delivering 30 or 32 amps of power. There are a few other companies like Clipper Creek for instance, that do offer a 40 amp EVSE, but for the most part, the industry norm is 30-32 amps, and even less in many cases. When buying any EVSE, make sure you find out what the maximum power the unit can deliver before purchasing it. I know more than one EV owner who bought an EVSE and didn't know it could only deliver 16 or 20 amps until they installed it. Why does 40 amps matter as compared to 30 amps? Well, for many EVs today, it doesn't. Only Tesla makes on board charging equipment that can accept more than 32 amps from a level 2 source, however that is going to change. I like to recommend future-proofing your garage, and if you're investing in a home charging solution which you may be using for ten or more years, why limit the charging supply to today's norm when home charging will only get faster as EV adoption increases? If your home has the capacity to add a dedicated 50 amp circuit (a 50 amp circuit is required for a continuous 40 amp load), then I say pay the few extra dollars today so you don't have to go back and upgrade in the future.
First, I'd like to point out the JuiceBox Pro 40 can deliver up to 40 amps of power. The vast majority of Level 2 EVSEs currently on the market are limited to delivering 30 or 32 amps of power. There are a few other companies like Clipper Creek for instance, that do offer a 40 amp EVSE, but for the most part, the industry norm is 30-32 amps, and even less in many cases. When buying any EVSE, make sure you find out what the maximum power the unit can deliver before purchasing it. I know more than one EV owner who bought an EVSE and didn't know it could only deliver 16 or 20 amps until they installed it. Why does 40 amps matter as compared to 30 amps? Well, for many EVs today, it doesn't. Only Tesla makes on board charging equipment that can accept more than 32 amps from a level 2 source, however that is going to change. I like to recommend future-proofing your garage, and if you're investing in a home charging solution which you may be using for ten or more years, why limit the charging supply to today's norm when home charging will only get faster as EV adoption increases? If your home has the capacity to add a dedicated 50 amp circuit (a 50 amp circuit is required for a continuous 40 amp load), then I say pay the few extra dollars today so you don't have to go back and upgrade in the future.
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My 2018 BMW i3s charging on the eMotorWerks Pro 40 EVSE |
The feature I love the most
about the JuiceBox Pro 40 is that is has built in WiFi and connects to
eMotorWerks servers. This allows for real time charging monitoring which
includes voltage and current measurement accurate to 0.2%. This is one of the
only EVSEs currently available today which allows you to monitor this kind of
charging data. I know a lot of EV owners, and one of the things that keeps
coming up is people asking how they can find out what the car is drawing during
charging. Having the ability to monitor your vehicle's electric draw is
particularly useful to BMW i3 owners like myself. The original 2014 i3 shipped with faulty onboard
chargers, causing many of them to fail. This resulted in
the car charging at half the speed than it was supposed to (15 amps instead of
30 amps). To make matters worse, while BMW engineered a new onboard charger,
the dealers were instructed to de-rate the i3's current charging capabilities
to about 24 amps, in an effort to keep the charger from failing. Many i3 owners
didn't know if their car was de-rated, if their charger had failed or if they
were charging at the full 30-amp rate. Without a way to really measure the
energy the car was accepting, many were left in the dark for a few months while
BMW built and installed the new, modified onboard chargers. This is just one example of why having the ability to monitor your charging can be useful. If they had an EVSE
that had the capability of displaying the rate the car was charging at, they
would never have to wonder what the car was capable of drawing since they could
simply look at the app when they plugged in.

The JuiceBox app has lots of useful information about current and past charging sessions. You can also set it up for notifications, start or end a charging session, raise or lower the output to the vehicle.
As mentioned above, the JuiceBox
Pro 40 doesn't need to be hardwired. Instead, it comes with a
NEMA 14-50 connector. This allows the owner to take the EVSE with them, all
they need to do is find a NEMA 14-50 receptacle and they can plug in. The 14-50
outlet is commonly used by RVs and thousands of RV parks across the country
have 14-50 receptacles where you can plug in on the road if needed. But in my
opinion, the real beauty of having a portable, plug-in EVSE is you can install
14-50 receptacles in places like your parents or friends home, or even work,
and take the EVSE with you and charge at your destination. This is much less
expensive than installing EVSEs in locations you may need to occasionally
charge at. The JuiceBox is small and light enough to take with you when needed.
You can see this on the photo above compared to the other EVSEs I have mounted
on my garage wall. The connector also has a rubber cap if you do mount or use
it outdoors. I also like that it’s the only EVSE with a sturdy
aluminum outer case. All of the other EVSEs have outer cases that are made of
plastic. eMotorWerks also offers a handy carrying case for those that use thier JuiceBox at multiple locations.
The app is very easy to set up and should take you less than
ten minutes to complete. There is also a web portal which you can log into for
past history charging info, set up notifications and view your current charging
status. eMotorWerks offers the Pro 40 EVSE in two versions: Standard and Lite.
The JuiceBox
Pro 40 costs $579.00 and the Pro 40 Lite costs $529.00. Both
units offer WiFi connectivity with the app, the difference is in the features
available. The Pro 40 Lite doesn’t have the “Smart Charger” features that the
basic Pro 40 does. These features include: Time of Use configuration, Amazon
Alexa voice activation, Load balancing across multiple EVSEs, notifications and
alerts. Many of these “smart” charging features aren’t going to be important to
buyers, but the charging history and notifications are definitely useful tools,
so I recommend considering the basic Pro 40. It’s only $50 more and there’s a
lot of features included for the slight upcharge.
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eMotorWerks offers a carrying case for the JuiceBox Pro 40. It's available on thier website for $49.95 |
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The Pro 40 Lite may be $50.00 less than the basic Pro 40, but it doesn't have any of the smart charging features. |
Personally, having a WiFi connected
EVSE is well worth the upcharge, and I highly recommend it. You'll really
appreciate the ability to look at your past charging sessions and energy
consumption and it definitely helps you to see exactly how much energy your EV
car uses, because you'll have a true "wall to wheels" measurement,
which includes charging losses. The in-car energy use calculators don't include
charging losses or the energy used from battery or cabin preconditioning while
charging, but this does. The difference can be significant, especially during
the winter months when the battery may need to be warmed while charging. The JuiceBox
Pro 40 comes with a 24 foot cable which is a little longer
than most standard EVSE cables. The extra few feet of cable can make the
difference of having to back into your garage or pull straight in, and possibly
allow you to park on either side of the garage in any position and still have
enough cable to plug in.
The home EV charging market is getting
better all the time. The products available today are more powerful,
lighter, some are portable and overall less expensive than the products
available only a few years ago, and this is welcome news to EV owners. I
recommend eMotorWerks products because I’ve used them for over three years now
and they are high quality and offer features that no other EVSE from any
competitor does. The price is right, the size is right, it’s powerful and
portable. If you’re in the market for a home charging solution, you definitely
should consider the JuiceBox
Pro 40.
Note: As with all of the electric vehicle equipment that I test out and review, I received the JuiceBox Pro 40 from eMotorWerks for free in retuen for my honest review. All thoughts and opinions here are my own and not influenced by eMotorWerks or their affiliated in any way.
Note: As with all of the electric vehicle equipment that I test out and review, I received the JuiceBox Pro 40 from eMotorWerks for free in retuen for my honest review. All thoughts and opinions here are my own and not influenced by eMotorWerks or their affiliated in any way.