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Tesla Model S Has Bizarre 'Vampire-Like' Thirst For Electricity At Night
cartechboy writes "The Tesla Model S, for all its technical and design wizardry, has a dirty little secret: Its a vampire. The car has an odd and substantial appetite for kilowatt-hours even when turned off and parked. This phenomenon has been dubbed the 'vampire' draw, and Tesla promised long ago to fix this issue with a software update. Well, a few software updates have come and gone since then, and the Model S is still a vampire sucking down energy when it's shut down. While this is a concern for many Model S owners and would be owners, the larger question becomes: After nine months, and multiple software updates,why can't Tesla fix this known issue? Tesla has recognized the issue and said a fix would come, yet the latest fix is only a tiny improvement — and the problem remains unsolved. Is Tesla stumped? Can the issue be fixed?"
No, because it's not using '180W'. It's using the equivalent of 180W draining for 24 hours. Compare with 180W draing for 5 minutes, the time component is important.
RTFA. One of the things the guy tried was to put a current draw device between the wall socket and the car and proved that it hadn't drawn any current overnight and that the power consumed had come from the car's batteries.
The on-board systems continue to suck juice from the vehicle's batteries overnight because Tesla has temporarily disabled (or diminished) their sleep mode due to some issue waking them back up (incidentally, that makes this issue hardly mysterious or "bizarre").
Sometimes the simplest answers indicate someone didn't RTFA.
No big mysteries here. Room for complaint that this issue hasn't been resolved quickly, though.
Tesla Model S uses a proximity sensor to detect the key fob in your pocket and extend the door handle with a motor:
http://www.consumerreports.org/cro/news/2013/05/video-sci-fi-wizardry-of-the-tesla-model-s-doors/index.htm
To quote from an article:
"From the instant you walk up to the Tesla S and the door handles motor out of the door, you know this isn't going to be like any other car you've ever driven. You open the door and the air conditioner has fired up, and your music is already playing. You put your foot on the brake, shift into gear, and you are off and running. There is no âoestartâ button. When you arrive, you just get out of the car; it turns itself off and locks up as you leave."
Tesla originally had a sleep mode for the inboard computer that was supposed to consume around 1%/day. But they found that the sleep mode often resulted in the car not detecting the key fob. So they disabled it until they could patch it. Not surprisingly, it sucks a lot of power while its sitting in non-sleep mode waiting for someone to walk by with the right key fob. If they had stuck with a manual door handle and a push start button for the engine, then the idle power issue would never have come up. In any case, Tesla is working on it and will resolved it eventually.
how about you simply don't plug it in unless you want to charge it? Duh!!!
Then the battery will discharge, about 5% of a full charge per day. Not leaving it on the charger just means more charge/discharge cycles for the battery.
Again, I love it when non-engineers talk out of their ass. Even top-o-the-line Fluke's don't go over 10A. They all need current clamps which are just one side of a transformer coil to step that current down into a usable range. If you want to directly measure high currents without said clamp, then you're still toting around a big ass ammeter which are still fairly expensive since they contain quite a bit of copper to carry that load. You won't be using a handheld meter for sure.
I think hitting a steel tow hitch at 70MPH is more than a little bump, or going through a concrete wall at 100MPh. People are blowing the fires all out of proportion. If a standard ICE car hit something like that in the engine compartment there's a good chance of a fire as well. In this case, since the battery is under the passenger compartment, a more likely scenerio would be for the debris to punch right through the floor and into the passenger compartment. Not one of the fires resulted in any damage to the passenger compartment of the car which cannot be said for most gasoline car fires I've seen.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
The average PC draws around 50-200W idle.
And as you said, this is more or less what the author found, except that he apparently has no idea how to convert kW/h per hour into watts.
Yes, he's a fucking moron.
Sorry, but you are wrong her. First, it's KWh (KiloWatthour), not KW/h.
The Watt is a unit that is used for measuring the amount of energy used per unit of time, in short 1 Watt = 1 Joule per second.
When electric energy is stored, like in a battery, or measured, the total energy stored or used is derived by multiplying Watts by time, thus Watt * seconds. Since this is not an easy workable unit, KiloWatts are multiplied by hours, and there we have the KWh.
So, if a battery has a capacity of 100 KWh, it is able of delivering 1000W for 100 hours, 500W for 200 hours, 100W for 1000 hours and 1W for 100,000 hours.
So, to make a long story short, the lost capacity of a battery HAS to be expressed in KWh, and the resulting loss of range totally depends on the driving conditions. It might be (numbers pulled from lower opening of intestine) 100 km when driving a constant 20 km/h, or 5 km when driving a constant 150 km/h, since the amount of power drawn on these speeds vary. But I hope you get the picture.
The qualification as a copulating, low-IQ person is totally yours.
What person will donate an airborne act of love?