When e-cars charge, they lock the plug in the socket. Why this is so and how this locking can prevent further travel.
Before an electric car can draw power at the wallbox or charging station, a mechanical interlock in the vehicle’s charging socket ensures a stable connection between plug and socket. At the charging station, this happens after the vehicle and charging station have made contact with each other via the charging protocol and the charging process starts. But even when the e-car is connected to a household socket, an electrically operated pin that pushes through a square hole in the edge of the plug blocks the plug from being pulled out.
An electrical lock (2) for the plug is located in the charging socket.
Why does the car lock the plug?
At the charging station, this interlock prevents third parties from interrupting the charging process by simply pulling the cable. For cables that are not permanently connected to the station, this is also an anti-theft device. The most important reason, however, is safety: If the plug were to be disconnected during a high-voltage charge, an electric arc could form. The problem is secondarily the current flow, but the high voltage between the open line ends. For this reason, the three-phase house plug should never be removed from three-phase wall boxes in full operation. At charging stations with Type2 or CCS connections, the cable is usually permanently installed at the charging point.
Does the interlock open again?
Basically, after the charging process has been completed or aborted. Exactly when depends on the vehicle or charging station in question: Some cars automatically release the lock after the charging process is complete, while in others the user has to unlock the vehicle additionally – either via the central locking system (e.g. Smart) or via separate buttons (e.g. Ford).
What does the light mean?