The J1772 is the standard AC charging connector for most electric vehicles sold in North America that do not use Tesla's connector. If you are planning a home charger, it is the connector you are most likely to need to match. This article explains what the J1772 is, how it works with a home charger, and what to check before you install one.
What the J1772 connector is
J1772 is the name of an SAE standard that defines the physical connector, pin layout, and signaling used for AC charging. The plug is round, has a latch, and uses several contacts for power, ground, and communication between the charger and the car. The same connector covers Level 1 charging from a standard 120-volt outlet and Level 2 charging from a 240-volt circuit.
How it works with a home charger
The J1772 is an AC connector. The charger on your wall supplies alternating current and does not convert it to direct current for the battery. The car's onboard charger does that conversion, and it has a maximum rate that sets the AC speed limit for the vehicle, no matter how powerful the home unit is. A 48 amp charger will not charge a car faster than the car's onboard charger allows.
When you plug in, the charger and the car exchange signals through the connector. The charger reports how much current it can supply, and the car draws up to that amount, or less if its own limit is lower. This is why one J1772 connector can work with chargers of different ratings.
Power levels and charging time
Level 2 charging on a 240-volt circuit is the usual choice for home installation. Power in kilowatts equals volts times amps, divided by 1,000. At 240 volts, a 40 amp charger delivers 9.6 kW, and a 48 amp charger delivers 11.5 kW, before losses. Level 1 charging on a standard 120-volt outlet is much slower, which is why most owners who want a home charger choose Level 2.
Charging time is roughly the battery capacity in kilowatt-hours divided by the charger's power. For example, a 75 kWh battery charged at 9.6 kW takes roughly 8 hours from empty. Real sessions take a little longer because of losses, and charging usually slows as the battery approaches full.
Plug-in or hardwired installation
J1772 chargers are sold for two kinds of installation. A plug-in unit connects to a dedicated outlet, commonly a NEMA 14-50 outlet, which is a 240-volt, 50-amp receptacle. A hardwired unit is permanently connected to a circuit by an electrician. The circuit has to be sized for the charger. A continuous load may use at most 80 percent of the breaker rating, so a 40 amp charger needs a 50 amp circuit, and a 48 amp charger needs a 60 amp circuit and must be hardwired.
Hardwired work should be done by a licensed electrician. Local permits and inspection may apply, so check with your local building department before installation begins.
Is my car a J1772 car?
Most non-Tesla electric vehicles in North America use a J1772 inlet for AC charging. Some vehicles use a different AC connector, and some have a combined port that adds large pins for DC fast charging next to the J1772 section. The owner's manual and the charge port on the car will confirm which connector applies to your vehicle. The article on how to tell which connector your EV uses walks through the checks step by step.
How this applies to EVIQO chargers
EVIQO sells three J1772 options, all 240-volt Level 2 chargers with a 25 ft cable and a 3-year warranty. One model can be installed as a 40 amp plug-in unit at 9.6 kW or as a 48 amp hardwired unit at 11.5 kW. A separate 48 amp hardwired model is also available, as is a 40 amp NEMA 14-50 plug-in model. A 4-year extended warranty is available for an additional charge. At 40 amps the chargers add about 38 miles of range per hour of charging, and at 48 amps about 46 miles per hour.