Electric Car Question

[griz]

It's common enough to hear of people driving away from gas pumps with the filler hose still attached.  When people do that with an electric car (and they will) what happens?  Is there an interlock that prevents it?  Do things get sparky when the battery shorts out?

[Nick1911]

Someone correct me if I'm wrong, but I thought the car won't move if there's a charger connected.  Might even be part of the spec.

I don't think the connector will cleanly separate with applied force in the direction a car is likely to move away from it.   I do think if the data lines are broken, the charger immediately opens the contactor shutting off power to the charging conductors.

[griz]

All the charging ports I've seen are on the side, so it does seem unlikely that it would simply unplug.  But drive offs are a foreseeable problem, so hopefully they have those logical safeguards in place.

[Fly320s]

Someone correct me if I'm wrong, but I thought the car won't move if there's a charger connected.  Might even be part of the spec.

Tesla has that feature.  I can't even put mine in gear with the power plugged in, even if it is not charging.

[MechAg94]

Tesla has that feature.  I can't even put mine in gear with the power plugged in, even if it is not charging.

That would be an easy way to disable the car if the switch didn't work or was faulty.  I wonder if you could rig a plug to simulate that with the charging port closed so it is not noticeable?

[dogmush]

I doubt it's a switch.  There has to be some data transmission between the charger and the car, especially on Tesla's, to throttle the power, and to tell the car if it's getting AC or DC.  Superchargers, in particular bypass the cars on board rectifiers and feed DC directly, and the current is managed by data coms with the car.

I'd bet money that the "we're plugged in don't move" functionality is software triggered by the data connection with the charger.  Probably with a back up sensor reading if the charge port door is open.

[Fly320s]

I doubt it's a switch.  There has to be some data transmission between the charger and the car, especially on Tesla's, to throttle the power, and to tell the car if it's getting AC or DC.  Superchargers, in particular bypass the cars on board rectifiers and feed DC directly, and the current is managed by data coms with the car.

I'd bet money that the "we're plugged in don't move" functionality is software triggered by the data connection with the charger.  Probably with a back up sensor reading if the charge port door is open.

I can charge my Tesla with household 120VAC.  Not data connection there.

[Fly320s]

That would be an easy way to disable the car if the switch didn't work or was faulty.  I wonder if you could rig a plug to simulate that with the charging port closed so it is not noticeable?

Hmmm, maybe.  When I charge at the airport, I have to use an adapter to get the airport charger to fit the Tesla connection.  When I disconnect, the adapter sometimes stays attached to the car and the charging door tries to close.  That tells me it isn't only a physical switch.  Maybe electrical.  Maybe magnetic.  Don't know.

[dogmush]

I can charge my Tesla with household 120VAC.  Not data connection there.

I was looking at the specs for the Supercharger plugs.  They have 5 pins, and there is some data on them.  If you are using the low voltage AC port, pluging it directly into the wall, there's probably a software "do I see voltage at the onboard rectifier" line.  That would also explain your adapter/charger door at the airport.  When you unplug the charger, it senses no voltage and closes the door, without considering the adapter.