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Tesla Model S achieves best safety rating of any car ever tested

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Re: Tesla Model S achieves best safety rating of any car ever tested

#201

Post by ssmoot »

mikeash wrote: post #41
guynamedloren wrote: post #37

Earlier quoted context omitted.

I don't know much about the mechanics or engineering of the Model S, but I'm going to take a gander and say that much of that extra weight comes from the battery pack (and other parts of the non-traditional drivetrain), which isn't a (huge?) factor in a crash test (though I could be wrong). Just checked - yep - the battery weighs an estimated ~ 545kg or 1200 lbs [1]. I'd expect the structural components to actually b…

How much does the gas tank, motor, radiator, transmission, etc. in a normal car weigh? Have to subtract that out of the 1,200lbs to see how much extra is added.

The 20+ gallon tank in my old Jeep Grand Cherokee would add over 300lb to the "wet weight". It also took (IIRC) an insane 7L of oil. So that stuff adds up.

Re: Tesla Model S achieves best safety rating of any car ever tested

#202

Post by James_Duval »

jbellis wrote: post #200
James_Duval wrote: post #174

Earlier quoted context omitted.

Would the tools used not be developed? I would've assumed the production of specialised tools for electric cars would be a priority once they become popular.

Presumably, avoiding electrocution of the passenger being extracted is also a goal.

I don't understand your response, is this not what the specialised tools would be primarily designed for?

Re: Tesla Model S achieves best safety rating of any car ever tested

#203

Post by kmfrk »

nraynaud wrote: post #152

Here in Europe we use EuroNCAP, do you have any news about a testing by this laboratory? Google doesn't yield any interesting result.

I was in a European Tesla retailer this month or the last, and the person told me that no tests NCAP test had been made at the time.

Re: Tesla Model S achieves best safety rating of any car ever tested

#204

Post by Ntrails »

gchpaco wrote: post #106
mikeash wrote: post #45

Earlier quoted context omitted.

I imagine NASA's crawler transporters would score exceedingly well on most of these tests, assuming the technicians survived.

Well considering they had a max speed of two miles an hour unloaded, you could probably jump off and get a beer before the crash happened.

"We're gonna crash, noooooooooooooooooooooo"

Flashbacks of Austin Powers and a steam roller...

Re: Tesla Model S achieves best safety rating of any car ever tested

#205

Post by JVIDEL »

axylone wrote: post #84
RomP wrote: post #22

This is simply unkind to the competition (and to the poles alike): "Tesla achieved this outcome by nesting multiple deep aluminum extrusions in the side rail of the car that absorb the impact energy (a similar approach was used by the Apollo Lunar Lander) and transfer load to the rest of the vehicle. This causes the pole to be either sheared off or to stop the car before the pole hits an occupant." There's winning an…

Here's the video of the Tesla pole test: http://youtu.be/_Al3IUHt9Wc?t=32s Honda Accord for comparison: http://youtu.be/ycntFFUfGkU?t=30s

That's an Accord coupe, the B pillar is more thick than a 4-door version, wouldn't that mean the sedan would score even worse?

Re: Tesla Model S achieves best safety rating of any car ever tested

#207

Post by el_zorro »

dmethvin wrote: post #195
triplepoint217 wrote: post #188

Earlier quoted context omitted.

Does anyone know what the actual voltages are? Just because it is high relative to the usual 12V of cars does not mean it is terrifically fatal. An anecdote to give you a picture of things: Electric arc welders operate at around 60V with a very large amount of current. However the electricity is not particularly the dangerous thing about them, it is the 9000F arc you are making and the molten steel. So to demonstrate…

These are very high voltages. The Tesla is 375 volts and the Prius is 275 volts.

Technically, that puts it well into the 'low-voltage' classification; generally, 1000 V is the threshold for 'high-voltage'.

Re: Tesla Model S achieves best safety rating of any car ever tested

#208

Post by ssmoot »

akira2501 wrote: post #70
mikeash wrote: post #65

Earlier quoted context omitted.

Yep, it gets a bit tough, but that 460-645lbs range seems like a decent stab at it. I don't get the impression that the Model S's motors are all that heavy compared to the rest of this stuff, but I could be wrong. I'd also wager that the Model S needs a full set of mechanical brakes for emergency purposes, since it still needs to be able to stop safely even if all the electronics suddenly quit while going down the hi…

A Chevy 383 can make about 400hp+ in about 620 pounds. If we choose all our numbers for comparable cars that are highly in favor of the Tesla, we're still only likely going to match the weight of the Tesla's battery pack alone. The Model S curb weight is 4,647 pounds. A Cadillac STS, which is 5" narrower but very nearly the same in every other dimension as the Model S is only 3,922 pounds. That leaves the Model S 725…

It's in the ball-park though. Your assessment seems pretty fair. I've seen some call the Tesla's weight "insane" though.

My old (still current gen) Volvo S80 T6 weighed 4,400lbs IIRC. I assume that's "dry" weight. Since a Model S is always "dry" aside from a gallon of wiper fluid or the like they probably weigh just about the same on the road. And the Model S is a bigger, faster car.

My Jeep Grand Cherokee (with the panoramic sunroof option I didn't actually have) weighed 5,500lbs. Again, I assume like motorcycle manufacturers that car manufacturers are listing the "dry" weight. So that baby is probably over 3 tons wet when optioned up.

The Cadillac seems on the light side for it's class. Even so, "wet" the difference in weight is probably one passenger. Despite it being a smaller car (5" actually seems pretty significant IMO, that's 5" less wiggle room to stay in your lane!).

That's (I assume) the worst-case-scenario highest capacity Tesla. Performance is far in excess of most cars on the road already. Capacity with smaller battery packs will surely improve. It seems like weight can only go down from here, and it's not out of line with it's competition as is.

Re: Tesla Model S achieves best safety rating of any car ever tested

#209

Post by JshWright »

sitharus wrote: post #120
abalone wrote: post #110

This is all very good PR.... BUT. The critical safety concern with the Tesla is....... You guessed it. The high voltage system. It can kill you or a first responder with a touch. It's not just about batteries catching fire, although that's gotten a lot of press lately. A chief concern during a Tesla accident is the exposure of high voltage components. It's a big concern for first responders. Read it from the horse's…

> All I'm saying is, never trust Elon Musk PR to tell you the whole picture. Never trust anyone's PR to give you the whole picture! Though as a counterpoint, I've seen cars with the roof cut off to extract people, but never the side doors or the floor cut open. I don't think they'd cut the floor since it's quite thick and has all sorts of wires and pipes anyway.

Firefighter here...

The major thing that concerns me about the Model S is the placement of the DC-DC converter in the front right wheel well. There's a common maneuver called a 'dash lift' where you make a couple relief cuts and then lift the dash using a hydraulic ram. Properly place, those cuts are dangerously close to that high voltage system.

Explanation of relief cut placement: http://advancedextrication.com/2011/12/closer-dash-lift-part...

EDIT: The video abalone posted has a great walk-through on rolling the dash of a Model S. http://www.youtube.com/watch?feature=player_detailpage&v=ntK...

Another issue is the seat belt pretensioner, which would complicated a 'side blitz' door removal (where both doors are removed as a unit), but that's a pretty standard place for the pretensioner, so it's something we're used to working around.

Re: Tesla Model S achieves best safety rating of any car ever tested

#210

Post by ciwk »

"While the exact number is uncertain due to Model S breaking the testing machine, what this means is that at least four additional fully loaded Model S vehicles could be placed on top of an owner's car without the roof caving in."

jeez.

couple that with this and it's safe to say these have been a good couple of months for tesla http://www.consumerreports.org/cro/news/2013/05/video-the-te...

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