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Standards

There are various international standard that are applicable to EV Charging. We’ll sumarize them here.

SAE J1772

This is probably the oldest standard and some of the others are derived from it. This standard describes the PWM signal communication between EV and EV Charger. It also describes the EV side of the protocol as well as the proximity protocol as available in the Type 1 plug.

SAE stands for  Society of Automotive Engineers. The organisation behind it is SAE International and is US based.

Noteworthy to mention is that there are no sockets defined for the EV Charger. The cable cannot be disconnected from the EVSE and thus forms an integral part of the EVSE.

You can read more here: https://en.wikipedia.org/wiki/IEC_62196

IEC 61851

The IEC 61851 has adopted many, if not all, specifications from the SAE 1772. For instance the PWM signal defined in this standard is fully compatible with it.

The IEC, International Electrotechnical Commission is based in Zwitseland and its standards are more focussed on the electric domain that the automotive domain. Needless to say that EVs are connected to the grid, making it an electric appliance.

IEC 62196

The IEC 62196 is a standard which defines the physical dimensions of sockets and the plugs for EVs and EV Chargers. The IEC 62196-2 refers to AC charging and the specific plug and sockets used for that.

The IEC 62196-3 refers to DC charging plugs and sockets.

For AC and DC plugs, it defines various shapes and standards which differ in shape, number of (electrical) connections, locking, and protocol. Most often those standard can be related to various countries or regions. For instance, a Type 1 plug, which is typically used in North America and Japan, doesn’t have support for three phases: The North American Network has 1 or 2 phases only.

The AC plugs Type 1 and Type 2 are physically not compatible but on the communciation level (IEC61851/SAE J1772) they are. This means that a charge cable can have a Type 2 plug on EV Charger side and a Type 1 plug on EV side.

Noteworthy to mention is that to prevent cables to be used as extension cord, the Type 2 female (on EV side) will not fit a Type 2 male (on Charger side).

Read further here: https://en.wikipedia.org/wiki/IEC_62196

ISO 15118

The ISO 15118 is a standard to add more possibilities for communication between EV and EV Charger. With this standard, EV’s can let the charger know their State of Charge of the battery. Also an unique owner or EV ID can be send to the EV Charger which can be used for authentication and thus billing. This makes it unnecessary to start a charging session with an RFID card or an app on your phone.

The ISO 15118 is a protocol on top of the PWN Signal. It will always be used in conjunction with IEC 61851 (or SA J1772). Both EV and EV Charger must have implemented ISO 15118 to start the more advanced communication and make use of the advanced features.

You can read more here: https://en.wikipedia.org/wiki/ISO_15118