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Shoshána Abigail 🏳️‍🌈 🏳️‍⚧️'s posts Post Back to profile
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Matt Seymour

@das_menschy @cgudrian @LilahTovMoon not sure what you mean, the video appears to show 120Vac on the exposed metal of the vehicle.

14 September at 21:12 | Wall-to-wall | Open on infosec.exchange
20 comments
RipNatenom #motorisierteGewalt

@Wifiwits @cgudrian @LilahTovMoon Ok, so I was wrong. I thought it's static electricity. My fault.

14 September at 21:13 | Open on toot.bike
Momo

@das_menschy
I'd LOVE to see the guy from the Straßenverkehrsamt's face when Tesla comes to them and ask for a License to put that... ... THING out on the road.
@Wifiwits @cgudrian @LilahTovMoon

14 September at 22:01 | Open on social.linux.pizza
Habrok

@momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon "No idea if we got the license or not. The inspector ran screaming towards the horizon and disappeared there. 🤷‍♂️" ;-)

14 September at 22:12 | Open on chaos.social
Comrade Weez

@Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon It's most likely the charger is miswired- they are using AC charging and line and neutral are reversed. Neutral should be at ground potential, so if there's LN reversed, the chassis of the device (appliance, Cyberturkey, wotever) will have line voltage present. However, there's no excuse for the vehicle not detecting this wiring fault and warning the user and disconnecting the AC charger- that part is on Tesla

14 September at 23:43 | Open on mastodon.social
christian mock

@weezmgk @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon I agree it's most easily explained by a charger issue, but how should the car detect that, given that it's not grounded itself? I think the charger would have to have not only L and N reversed, but also PE connected to L, plus probably no RCD.

15 September at 0:01 | Open on chaos.social
Comrade Weez

@cm N & earth should be at at the same potential (or mV close to it). If it isn't, the car should disconnect and go into a fault mode and put an alarm notice somewhere (dash cluster? Display screen?) This is what they pay the EEs big bucks for. @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon

15 September at 0:09 | Open on mastodon.social
christian mock

@weezmgk @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon What the car sees on L, N and PE might not be the same as the outside world does, assuming sufficiently malicious wiring in the EVSE. And without a stake in the ground you can't really determine whether the wire labeled "PE" is at that potential.

15 September at 0:30 | Open on chaos.social
Comrade Weez replied to christian

@cm There's an earth reference in the charge connector, which should be sufficient to determine if L&N are correct or reversed. Most device design simply trusts that the sparky who wired the residence didn't cock it up. But it is possible to detect such a fault and protect the user from it. At the price of an EV, I would rather expect that feature would be there, it's not a toaster. @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon

15 September at 0:41 | Open on mastodon.social
Vlad 🇺🇦🦀 replied to Comrade

@weezmgk It’s rapidly approaching a toaster if you stand barefoot and touch the wheel while charging in this situation :/

15 September at 6:30 | Open on hachyderm.io
Zimmie

@cm @weezmgk @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon That’s my suspicion. The adapter probably doesn’t properly detect L/N swapping and only checks to see if N and PE have potential. Wire it sufficiently incorrectly and it puts hot on the output. Or maybe the car assumes N and PE are the same thing and has the chassis connected to N (or to both).

As for how to detect it, once you have power, it’s pretty straightforward to make a DC reference and check for AC potential between that reference and each input line. You can’t confirm whether a given line is actually earth versus something with DC bias, but you can tell whether AC exists in the absence of significant load. Think like running a set of non-contact voltage testers. Then only engage the relays (or IGBTs or whatever else you may want to use) to draw from the feed if you don’t detect AC on the PE line or N line.

@cm @weezmgk @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon That’s my suspicion. The adapter probably doesn’t properly detect L/N swapping and only checks to see if N and PE have potential. Wire it sufficiently incorrectly and it puts hot on the output. Or maybe the car assumes N and PE are the same thing and has the chassis connected to N (or to both).

15 September at 3:41 | Open on infosec.exchange
apalrd

@weezmgk @Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon

J1772 is used for both 120v and 208/240V, so the same two pins are use for L+N and L1+L2. There's no reason to care what the potential of L and N are relative to PE for the onboard charger, the charger just needs to draw current from the two line inputs at whatever potential they are relative to each other.

This seems like the PE is connected to line.

15 September at 3:04 | Open on hachyderm.io
🐧DaveNull🐧 ☣️pResident Evil☣

@weezmgk What do you mean ? Even if Neutral and Live wires were inverted in the charger wiring, which sucks already, the chassis wouldn't be under 120 V… Neutral IS NOT supposed to be connected to chassis. That's Protective Earth Wire role to ground chassis.

PE and N have to same potential, 0V, but aren't supposed to be connected to each other. If electried chassis is connected to Neutral, it wouldnt be properly grounded…

@Habrok42 @momo @das_menschy @Wifiwits @cgudrian @LilahTovMoon

15 September at 6:24 | Open on mamot.fr
Jeff Grigg
Comrade Weez

@JeffGrigg most drivers of any type of car experience static shocks. Caused by rubbing clothing fabrics on car upholstery. If the driver wears rubber soled shoes, there will be a charge potential difference from ground until the driver touches a grounded object. This can be a problem when pumping petrol into a vehicle. @das_menschy @Wifiwits @cgudrian @LilahTovMoon

15 September at 0:54 | Open on mastodon.social
Chookbot

@JeffGrigg I had minor static electricity problems with my ICE cars.

15 September at 3:06 | Open on theblower.au
Javier

@das_menschy @Wifiwits @cgudrian @LilahTovMoon

DC is way more like AC than static.

120v DC is almost as dangerous as 120v AC, while 120v of static is nothing compared to rubbing feet on a carpet. (typically into the thousands)

15 September at 0:42 | Open on mstdn.social
guenther

@das_menschy @Wifiwits @cgudrian @LilahTovMoon

holy shit, you're right! in the last bit of the video, it's visible that the multimeter is set to AC. so basically they connected the charger's phase wire to the body?

15 September at 5:40 | Open on chaos.social
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