Is this just tricking a sensor into thinking it is cooler, or actually keeping the parts that matter cooler? If its the latter this is a great trick. If its the former, it's a hazard.
Nothing pedantic about it. We live in an era where people ought to understand the difference between power (measured in watts) and energy (measured in joules, or calories, or watt-hours).
But for some reason this is widely misunderstood, resulting in frequent errors and poor decision making. The Times, a generally-reputable UK newspaper, once published a front page headline declaring that electric vehicles would require the equivalent of 20 new nuclear plants to be built in the UK. None of their fact checkers noticed that the entire article was based on an error that confused GWh (energy) with GW (power).
The fire alarm IS the senor, it's an alarm, it's in the name, it's pretty obvious to most people what happens if you fuck with it and what the consequences are, and people still do to combat false positive alarms.
But most people have no idea about the senor(s) in tesla charger plugs, since it's a plug, not an alarm. How should it be obvious for the average layman without open disclaimers? People always tend to fuck with stuff they don't fully understand if someone tells them that doing something quirky means extra oomph.
And forget about people putting towels on it, what about rain or wet debris falling on it? Seems like edge cases that should have been covered during the concept and design phase by EEs with experience. For something meant to survive and be used outdoor these are not even edge cases.
Are we confusing smoke detectors with fire alarms? Most people screw with the detectors. A fire alarm is usually triggered when a sprinkler head is set off. And despite what Hollywood shows us, just because one head starts does not mean all of the heads in the system open up.
I think that one depends on the system. I had a highrise fire safety training and I asked how other sprinklers knew to fire if they were heat activated and it turns out the pumps would kick out enough pressure to knock the other caps off.
Depends on whether the important part to keep cool is the part of the handle that the towel dissipates heat from, or if that temperature reading is used as a proxy for the temperature of the entire cable.
Yeah, but since it's charging faster, it'll be done before the inaccurate temp readings allow the actual cable to melt. Or, if it's not the charger in your home and you're using someone else's charger, who cares if it melts. That's someone else's problem as long you get your batts topped off. At least, that's my cynical internal dialog for the world's mentality today.
The towel doesn't really cool the cable, it just cools the temp sensor, which means now an important safety feature is indicating inaccurately. Best case, this could wear out the charger more quickly. Worst case, it wear out or damage your battery.
It might be. Often the most restrictive thermal limit most products face is for touch safety (50 ~ 80 C, depending on the material's thermal conductivity and the extent of contact). For a handle that will be quite restrictive, because you'll be firmly gripping it. The materials themselves would probably survive substantially higher temperatures before failure. I'd guess that the first to fail would probably be adhesives and plastics, but they'd be engineered to survive hot days in direct sun, even if the handle gets too hot to touch safely.
(Disclaimer: I don't work for Tesla, and did not design the supercharger cabling, this is educated speculation).
It's different, it's sort of very shallow submersion. IPX2 is the rating for angular rainfall; immersion (admittedly up to a meter of pressure, as it were, not just a towel wrap) is IPX7. I think certainly you could have a 'rainproof' product not withstand a wet towel.
I assure you that a wet towel is nothing like immersion. Immersion has significant pressure differentials, which is why IP ratings factor time as well.
If you don't believe me, wipe your computer down with a wet towel. Still works right?
Now submerge it, even briefly, and observe its functioning.
You could write the same comment about it being nothing like dripping or spraying water ('If you don't believe me ... Now blast a hose at it') which was my point.
Different respondent here. I'd put it a different way. I don't think there's a realistic chance of problems with water infiltrating the charger from a wet towel. Maybe overheating, but I don't know about that.
That's fine, I've never seen one of them, I wasn't making a judgement on that. I said 'I think you could certainly have a product [...]'. Any porous material would be a lot more resistant to rain than the wet towel, for example.
Interesting that the V3 superchargers use a liquid-cooled cable. Without knowing anything specific, this implies that maintaining cable temperature is the objective, not just the handle. That means that the handle sensor proxies the temperature of the entire cable. I would imagine they measured the heat-dissipation site where the coolant flows to to be where they measure the temperature for regulation, rather than the handle.
Just because they advertise "liquid-cooled cable" doesn't mean that the primary intended beneficiary of the cooling effect is the wire-bits. It could instead be the handle-bits.
Both of these bits are constituent parts of the greater assembly commonly called a "charging cable," which includes [at least] both wire and connectors, and sometimes a handle.
From a safety design standpoint, surely multiple redundant temperature sensors is the only way to go right?
The user might "life-hack" the cable into acting like a fuse with it in the handle, having it halfway down the cable risks complications like that portion of the cable lying in a puddle etc.
With good enough coverage, if they can all be kept cool, the cable likely is as well.
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[ 3.7 ms ] story [ 117 ms ] threadHowever, it does raise the question if a shaded plugin spot, or rain could also present a similar fire hazard.
But for some reason this is widely misunderstood, resulting in frequent errors and poor decision making. The Times, a generally-reputable UK newspaper, once published a front page headline declaring that electric vehicles would require the equivalent of 20 new nuclear plants to be built in the UK. None of their fact checkers noticed that the entire article was based on an error that confused GWh (energy) with GW (power).
> Please don't fulminate. Please don't sneer, including at the rest of the community.
Unfortunately there is no report button.
But most people have no idea about the senor(s) in tesla charger plugs, since it's a plug, not an alarm. How should it be obvious for the average layman without open disclaimers? People always tend to fuck with stuff they don't fully understand if someone tells them that doing something quirky means extra oomph.
And forget about people putting towels on it, what about rain or wet debris falling on it? Seems like edge cases that should have been covered during the concept and design phase by EEs with experience. For something meant to survive and be used outdoor these are not even edge cases.
I assume the down votes are from people assuming you agree with, or take part in "because everyone else does so why shouldn't I", that mentality.
Of not, then you might want to clarify. Otherwise, I'm glad that in all likelyhood we'll never meet in real life.
Did that not have the intended effect of stating that's how I feel other people think?
To others, apparently not.
I have the same problem occasionally.
(Disclaimer: I don't work for Tesla, and did not design the supercharger cabling, this is educated speculation).
If you don't believe me, wipe your computer down with a wet towel. Still works right?
Now submerge it, even briefly, and observe its functioning.
You could write the same comment about it being nothing like dripping or spraying water ('If you don't believe me ... Now blast a hose at it') which was my point.
Yes, but you also said it was more than rainfall. A towel is so overly shallow that it becomes less than rain.
> Any porous material would be a lot more resistant to rain than the wet towel, for example.
That doesn't sound right to me. Rain will stick around in spots, and those spots will be wetter than under a towel.
It has to be more in some way for your argument to make logical sense.
Or was I unclear that I meant "more in some situations than rain ever is". If that's it, then sorry, my bad.
All quite interesting.
Both of these bits are constituent parts of the greater assembly commonly called a "charging cable," which includes [at least] both wire and connectors, and sometimes a handle.
Probably a market for setups that have water cooling jackets.
The user might "life-hack" the cable into acting like a fuse with it in the handle, having it halfway down the cable risks complications like that portion of the cable lying in a puddle etc.
With good enough coverage, if they can all be kept cool, the cable likely is as well.