WHAT is J1772

Whether you have seen the Chevy Volt, the Nissan LEAF, the Tesla Model S, or the newer Prius that can plug in, they all use the SAE J1772 standard to connect and charge.

The SAE J1772 standard defines how a charging station should communicate with and charge electric vehicles. In short, this is the standard that defines how EVSE connects.

In this standard, the Electric Vehicle Supply Equipment (EVSE) manages the link from the grid or household power to the electric vehicle. It will always have a constant connection with your car to check if it needs to charge. It is an easy-to-install device that saves money and prevents any possible accident with your batter. EV sales have increased, but no federal agency J1772 is required to sell EVs in the United States.

You will need an intelligent, onboard AC-DC converter to step up the EVSE AC output and rectify the DC in the onboard battery pack. It is EVSE smart because it communicates via the J1772 protocol and commands the power of the AC-DC adapter.

The original standard specified 120VAC charging (generally less than 16A) for Level 1 charging, and 240VAC charging (usually less than 32A) for Level 2 charging. All-electric vehicles and plug-in hybrids are currently available with Level 2 charging, which means they can recharge the batteries by plugging them in.

The EVSE’s J1772 connector provides Proximity and Ground pins that detect the EVSE plug when connected. The electric vehicle charge port is the EVSE, which can use the power to recharge the battery. There is no need to worry about the battery dying when you park in your garage. The charging station will not work until there is enough power to get electricity from the grid when the vehicle is parked. It does not happen in all cases, as EV manufacturers appear to have all chosen to be compatible with the lowest available (13A) charge current (the Volt, LEAF, and other major supplied EVSEs that come with the vehicles only output this).

DC fast charging is a new feature of the J1772 standard. An EVSE not only connects to a vehicle battery and provides AC charging, but it also provides DC power. SAE J1772 has added this: Audi, BMW, Daimler, Ford, General Motors, Porsche, and Volkswagen have all agreed to implement this as their direct DC charging standard.

Types of J1772

  1. J1772 adapters 
  2. J1772 chargers 
  3. J1772 plugs.
  1. J1772 adapters

Some plug-in electric vehicles are currently on the road. There are two types of chargers available for home charging. They include the Level 1, Level 2, and the DC fast charge. They are the charger that came with your vehicle, plus a portable charger, a cord, and a wall charger.

All-electric cars come with a cable adapter that can be plugged into any standard 120V outlet, and either a J1772 or SAE plug on one end and a three-prong plug on the other. It can charge up to 125 miles per hour in about 20 hours. There is a special charger that is designed to work specifically with the car and is sold separately. With a 240V charging station, these are plugged into a 240V outlet and, depending on the charger, can charge 3-7 times faster than other charging options.
Your car charger will have an SAE J1772 connector, and you will find these at offices, grocery stores, and parking garages. They can be installed anywhere and purchased anywhere. Every newer plug-in electric vehicle uses the SAE J1772 standard for charging. In the US, especially, this is the best way to charge your EV. Standard is an agreed-upon way of doing something and includes technical specifications to be used consistently as a rule or guideline. In this case, the SAE J1772 standard represents how the car relates to and charges the electric car.

  1. J1772 plugs

The North American standard for electrical connectors for electric vehicles is SAE J1772 or “J” plug. It covers the general physical, electrical, communication protocol, and performance requirements for the electric vehicle conductive charge system and coupler. This document defines a common electric vehicle conductive charging system architecture. It also includes the operational requirements for such a system and the functional and dimensional requirements of the vehicle’s inlet and mating connectors.

The J1772 standard supports a wide range of single-phase AC charging rates, from 2.44 kW (12 amps @ 120 volts) to 3.2 kW (80 amps @ 240 volts) from an EVSE, and up to 80 amps from a wall-mountable charger. There is a 7-pin Combo Coupler with a 5-pin J1772 connector and a CCS 2-pin connector that supports fast-charging up to 350 kW.

  1. J1772 chargers

The J1772 chargers are compatible with most level 2 public charging stations and support charging speeds of up to 19.2kW. Most public charging stations use SAE J1772 chargers compatible with most brands of electric vehicles. 

For this reason, each EV sold comes standard with an SAE J1772 charger making it easier for EV owners to charge their vehicles at the standard charging stations available to the public. More recently, electronic vehicle charger manufacturers have also started to make chargers suitable for connecting the standard SAE J1772.

What are the pros and cons?

PROS

  • The J1772 provides connectors and standard PINs to allow detection that the EVSE plug is not charging even when connected.
  • The EVSE identifies its maximum current or the power that it can provide, to the vehicle via a unique tone and an indicator light.
  • The standard allows vehicles to be connected to an EVSE that does not have enough charging power to keep a car fully charged.
  • There’s no charging current compatibility between different EVs. 
  • DC fast charging is a new feature of the J1772 standard. 
  • They can be installed anywhere and purchased anywhere
  • This product is designed to make EV charging quick and effortless.
  • Compact and durable,

CONS

  • The Orion 2 BMS will not engage the J1772 EVSE station
  • The Proximity Detect input is registering an invalid voltage
  • The J1772 plug state goes to “Ready” but the EVSE does not engage (the state does not change to “Charging”)
  • The J1772 EVSE activates but the BMS is restricting the maximum power output too much (charger not charging fast enough)

What is the charging speed? 

Direct Current (DC) charging has one primary advantage: speed. There are many things to consider when thinking about how long it will take to recharge the Leaf. The 16kWh battery packs, the SAE level 2 maximum of 63A, and the 12-volt standard home outlets. All add up, but with the 24kWh LEAF, you should be good to go, even at peak demand. In the case of a LEAF, 24kWh battery charging at a Level 2, 30A rate (30A x 230V = 6.9kW) will take about 4 hours to recharge.


Does J1772 work for fast chargers?

When traveling, it’s especially important to have a power source that’s reliable and high current. And when you need a quick charge, you also want high voltage. You won’t need to find enough space to safely manage high-power adapters, charging stations, and fast currents. This depleted 24 kW battery can be fully recharged in less than an hour. That is almost half of its total capacity. But wait! There is more. “Level 3” DC fast charge is the still-developing portion of J1772 that is not yet formally defined. However, it could provide up to 240kW of charging!