Possible common indicators for intermediate disconnect could be:

• Status changed (A is the ultimate hard indicator)
• ChargedEnergy jumps back (weak indicator)
• ChargingTime jumps back (weak indicator)
• Identifier changed (be carefull, may change even if session is still running by just swiping any other card. Depends on charger firmware! May be a strong indicator if implemented correctly.)
• TransactionId changed (OCPP only. Is a strong indicator but attention: Id may be reused by charger!)
• ...?

tbc

When charging cable is connected could evcc not check once in a while which vehicle actually shows connected? When changing happened to fast I checked in configuration and the disconnected vehicle showed disconnected (as it should) and the other one showed connected in the status (configuration page). Yet, evcc still thought that the first car is still hooked up.

could evcc not check once in a while which vehicle actually shows connected

It does.

When changing happened to fast I checked in configuration and the disconnected vehicle showed disconnected (as it should) and the other one showed connected in the status (configuration page).

This issue ist not about vehicle identification by vehicle API, but about vehicle identification by charger. Doing via API is not possible as API calls are scarce and can only be triggered if we identify vehicle disconnect by charger.

This issue ist not about vehicle identification by vehicle API, but about vehicle identification by charger. Doing via API is not possible as API calls are scarce and can only be triggered if we identify vehicle disconnect by charger.

I experience this as a "bug" currently. Not sure if I should open a new issue.
Attached two screenshots - one export from wallbox, one from evcc. The "unser Passat" car is identified by rfid token "blau" while the standard car at this loadpoint is "Hyundai Ioniq 5".
Marked in red: The values read from the wallbox export are correct (Passat only has a 10,x kWh battery) while evcc attributes more of the charged power to that session - I assume because of a "fast switch" - both cars were parked and unplugging/plugging takes me 5 seconds.

Also, the yellow marked identifier doesn't make sense in my configuration. "Hyundai" cannot be identified by RFID token "Blau"

If my explanation doesn't make sense - please let me know.

PR zum Test. Da wir die Fahrzeug-APIs dafür nicht nutzen können passiert das nur wenn die Wallbox einen Identifier zurück gibt.