Not Every Charger Is Created Equal
These EV chargers use a higher-output 240 volt power source. This is the same type of circuit that you plug a clothes dryer into. Charging times are much faster than with a Level 1 EV charging station. A Mercedes BClass 250e, for example, can take 20 hours to fully charge (87 miles of range) with a standard 120 volt charging station A 240 volt Level 2 charger can fully charge a 250e in 3 hours.
Most EV owners charge their vehicles at home 85% of the time and upgrade to a Level 2 charging station to make use of the fast charging soon after buying their first electric car. A high-speed charging station at home is much more convenient and can also add to your home's resale value.
Installing a Level 2 charging station requires a certified electrician to run a new circuit from the home's breaker or fuse panel to where the vehicle will be plugged in, and may require other upgrades to the home's electrical system.
Depending on the city you live in, a qualified electric contractor must obtain an electric permit, file an application with your electric utility, and obtain an inspection. All upgrades must meet appropriate NEC and UL state and local code requirements.
These charging stations plug into a normal 120-volt connection which uses any standard household outlet; there are no extra costs here. The downside is that charging times can be slow. Many electric vehicle owners will likely find that they typically deplete more of the battery than can be replenished overnight using a basic 120 V connection.
These fast-charging devices use very high voltage accessible only on commercials grids and can, in some cases 90 or more miles of range to an EV in just 30 minutes. These chargers, however, are extremely expensive, costing tens of thousands of dollars, and routinely using a level 3 charger can ultimately hurt you car's battery, so we wouldn't consider one for home installation; they are also cost prohibitive for most EV owners.