# IEC 61851

IEC 61851 is an international standard for electric vehicle conductive charging systems, parts of which are currently still under development$^{(written2017)}$. IEC 61851 is one of the International Electrotechnical Commission's group of standards for electric road vehicles and electric industrial trucks and is the responsibility of IEC Technical Committee 69 (TC69).

## Standard documents

IEC 61851 consists of the following parts, detailed in separate IEC 61851 standard documents:
* IEC 61851-1: General requirements
* IEC 61851-21-1: Electric vehicle on-board charger EMC requirements for conductive connection to AC/DC supply
* IEC 61851-21-2: Electric vehicle requirements for conductive connection to an AC/DC supply - EMC requirements for off board electric vehicle charging systems
* IEC 61851-23: DC electric vehicle charging station
* IEC 61851-24: Digital communication between a DC EV charging station and an electric vehicle for control of DC charging
* IEC 61851-25: DC EV supply equipment where protection relies on electrical separation

## IEC 61851-1

IEC 61851-1 defines four modes of charging:
IEC 61851-1 charging modes :
| Mode | Diagram | Limits | Limits | Limits | Supply & Interface | RCD Protection | Applications | Notes |
| Mode | Diagram | Phases | Current | Voltage | Supply & Interface | RCD Protection | Applications | Notes |
| 1 | EV connected directly to AC grid | 1φ | 16A | 250V | AC, non-dedicated | | electric bikes, scooters, trickle-charging | Direct connection of vehicle to conventional electrical outlets. Not allowed in the US, Israel, and United Kingdom; prohibited for public charging by Italy; restricted in Switzerland, Denmark, Norway. |
| 1 | EV connected directly to AC grid | 3φ | 16A | 480V | AC, non-dedicated | | electric bikes, scooters, trickle-charging | Direct connection of vehicle to conventional electrical outlets. Not allowed in the US, Israel, and United Kingdom; prohibited for public charging by Italy; restricted in Switzerland, Denmark, Norway. |
| 2 | EV connected to AC grid through cable incorporating RCD protection | 1φ | 32A | 250V | AC, non-dedicated | | "slow AC" | Requires control box between vehicle and electrical outlet incorporating RCD protection. Prohibited for public charging by Italy; restricted in US, Canada, Switzerland, Denmark, France, Germany and Norway. Typical portable / "home" charger. |
| 2 | EV connected to AC grid through cable incorporating RCD protection | 3φ | 32A | 480V | AC, non-dedicated | | "slow AC" | Requires control box between vehicle and electrical outlet incorporating RCD protection. Prohibited for public charging by Italy; restricted in US, Canada, Switzerland, Denmark, France, Germany and Norway. Typical portable / "home" charger. |
| 3 | EVSE connected to AC grid, supplies EV using tethered cable or socket-outlet with bidirectional communication | 1φ | 32A | 250V | AC, dedicated (IEC 62196-2) | | "slow and quick AC" | EVSE permanently connected to electrical grid; includes RCD protection and bidirectional (EVSE/EV) communication. Typical public AC charger installation. Tethered (cable permanently attached) & untethered (dedicated socket outlet only) configurations. |
| 3 | EVSE connected to AC grid, supplies EV using tethered cable or socket-outlet with bidirectional communication | 3φ | 32A | 480V | AC, dedicated (IEC 62196-2) | | "slow and quick AC" | EVSE permanently connected to electrical grid; includes RCD protection and bidirectional (EVSE/EV) communication. Typical public AC charger installation. Tethered (cable permanently attached) & untethered (dedicated socket outlet only) configurations. |
| 4 | EVSE rectifies AC grid & supplies DC power to EV using tethered cable with bidirectional communication | – | 200A | 400V | DC, dedicated (IEC 62196-3) | | "fast DC" | Current conversion handled by EVSE, not EV. |