Charger VS EVSE (Electric Vehicle Supply Equipment)
Electric vehicle (EV) chargers come in various shapes and sizes. Each with different pros and cons. What they all have in common – is that they are not actually chargers at all. EV chargers are actually a type of Electric Vehicle Supply Equipment (EVSE).
Much like a ‘phone charger’ they are misnamed. In fact an ‘EV charger’ is essentially just a power supply. Because EV batteries come in various shapes, sizes, chemistries and voltages, ‘charging’ is done by the EV – as it is programmed and designed to manage its own battery best. The only electrical conversion that occurs within an EV charger is for the small amount of electronics that the EV uses for its own lights and circuitry.
EV chargers – are a bit smarter than your phone charger luckily – and we’ll dive into those aspects here. Largely though, an EV charger has the single task of safely delivering power to your electric vehicle.
AC Current Charging – AKA Slow Charging
There are Level 1 chargers and level 2 chargers, each referring to the different voltages supplied to the EV.
Level one refers to 120 volts supplied to the EV. Level 1 for instance would be a common wall outlet.
Level 2 refers to 240 volts supplied to the EV. Level 2 would be more likely a dedicated circuit of various amps, typically ranging between 16 amp and 40 amp circuits.
DC Current Charging – AKA Fast Charging
DC current charging is often referred to as fast charging. DC chargers, like the Tesla Superchargers, you may find at commercial offices or buildings. These chargers require significant infrastructure upgrades – and in some ways are much like a gas pump. DC chargers are not the type you’d likely be able to install or find in a residential setting. Because plugging in at home is convenient and ideal for most EV car owners, DC chargers are not our focus in this article.
Within the Electric Vehicle
For some car talk, we’ll briefly outline the electrical pieces within an EV.
Junction box –separates the battery voltage supplied to the inverter module and the high-draw power car accessories, such as the air-conditioning compressor and the car cabin heating elements.
Inverter module - Runs the traction motor and manages charge during regenerative braking.
DC to DC converter – Much like an alternator, this converter takes the high voltage DC current from the AC Charger and steps it down to approx. 13.8 volts. This low voltage DC charges the standard car accessories and 12V battery. EVs still have a standard 12V lead-acid battery to simplify things for standard maintenance. This battery allows EVs to use the same bulbs, computers, power window motors, cigarette lighters etc. 12 volts is also far safer for technicians working on the car, than the higher voltage DC power.
Onboard charger – This is the ‘charger.’ Taking the AC power from your ‘EV Charger’ it converts the power into DC and charges the battery pack at their required voltage. Within the battery pack there are various modules and monitoring systems. These systems, part of the on board charger, are able to pull more power from the grid then your home’s circuit can provide safely. This is where the ‘EV Charger’ comes in – and takes over the job of managing how much current the onboard charger can draw at a given time.
Behind the Enel X JuiceBox
One of our favorite EV chargers on the market is the Enel X JuiceBox. Made by the first company to bring smart EV chargers to the market, they have expanded from the original design for a second generation EV charger with all the bells and whistles. The JuiceBox is compatible with nearly every EV and offers numerous upgrades that other EV Chargers do not.
With integrated cable management & connector holster, the charging cable can loop around the mount for easy storage. Which is great because you won’t find an EV Charger with a longer cable. The JuiceBox comes with the longest cable allowable by the NEC – 25 ft long!
Depending on your home’s circuit panel availability, the JuiceBox comes in three different power level options. There is the 32 amp – delivering up to 7.7 kw, The 40 amp – delivering up to 9.6 kw, and the 48 amp – Delivering up to 11.5kw. Following the NEC each dedicated circuit must follow the 125% rule. Therefore the JuiceBox 32, needs to be on a dedicated 40 amp circuit, the JuiceBox 40 needs to be on a 50 amp dedicated circuit, and the JuiceBox 48, requires a 60 amp dedicated circuit. The smaller sizes of the juice box come in plug-in versions, while the JuiceBox 48 requires hard wiring & and a qualified electrician to install.
The JuiceBox offers a NEMA 4 exterior enclosure – which is higher than other EV chargers, which often only offer NEMA 3. This NEMA 4 enclosure protects your EV Charger from the sturdiest storms and the hardest winds.
The JuiceBox, unlike many other EV Chargers on the market, is even Energy Star Certified.
In the event of a power outage, the JuiceBox offers automatic restart. Automatic restart means the EV charger will be ready to delivery power to your vehicle once power is restored. Some cars don’t play perfectly with automatic restart however. The JuiceBox will reinitiate a charging session, but you might need to un-plug and plug-it-back-in depending on your EV.
That’s becoming less common with newer EVs luckily.
There are simple chargers, where you plug in your EV Charger and it provides power to your EV. There are also smart chargers, which can save you time and money in the long term, as well as make your EV experience more hands on.
With the JuiceBox App, you can track all sorts of charging and use info. You can track things such as:
Real time statuses - such as the current charging status, how long it’s been charging and real time Stop/ Start from your app
Reminders to Charge your car - for example at bedtime on a school night.
Review past charging sessions
Track how much power your EV has used charging, thus how much it costs you each month in electricity.
Track mileage range per charging session
And perhaps most importantly smart chargers can allow you to work with your local utility provider.
Perhaps this will be of greater and greater need as time goes on and the grid feels more and more strain in its switch to renewable. However it also is a great added benefit EV owners can tap into today. Grid utilities have peak and off peak rates. Simply when it’s working hours and all the AC units in a city are running – there is more demand for electricity, and thus peak hours. Rates for electricity in peak hours are greater than the rates charged in off hours. With Smart chargers you are able to collaborate with your local utility. By providing them access to your charger remotely, the EV Charger can be set to operate in off-peak hours, lowering your electric bill costs. Perhaps you come home and plug in your car at 6:00pm, but peak hours end at 8:00pm. With this feature your car will start charging at 8:00pm.
Our last and favorite feature of the JuiceBox is its power share feature.
Very few EV Chargers offer this seemingly essential smart function. With the JuiceBox two vehicles can share one circuit. The JuiceBox does this by carefully charging one vehicle at a time. The JuiceBox will charge one car, then once finished charging it will switch to begin charging the second vehicle.This is a great space and money saver if you have two EVs but don’t want to install an entirely second electrical circuit.
UL listed with a three year warranty – considering a JuiceBox for your home EV charging needs!