[HN Gopher] Putting a Wet Towel on a Tesla Supercharger Handle G...
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       Putting a Wet Towel on a Tesla Supercharger Handle Gets Faster
       Charging Speeds
        
       Author : peutetre
       Score  : 9 points
       Date   : 2024-05-08 01:22 UTC (1 days ago)
        
 (HTM) web link (insideevs.com)
 (TXT) w3m dump (insideevs.com)
        
       | advisedwang wrote:
       | 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.
        
         | malfist wrote:
         | Considering the super chargers only have the single temperature
         | sensor in the termination point, this is certainly a fire
         | hazard.
         | 
         | However, it does raise the question if a shaded plugin spot, or
         | rain could also present a similar fire hazard.
        
       | vipa123 wrote:
       | Next week the article will be "Tesla battery fires linked to use
       | of wet towel during charging"
        
       | seanhunter wrote:
       | That classic combination of water with electric current, and
       | tricking a safety sensor to boot. What could possibly go wrong?
        
         | TheTxT wrote:
         | It's only 250 kilowatts of energy, so nothing really.
        
           | s0rce wrote:
           | pedantically, 250 kW of power
        
         | Rinzler89 wrote:
         | Methinks safety sensors shouldn't be designed to be so easily
         | fooled.
        
           | llamaimperative wrote:
           | That's an excellent Darwin Award acceptance speech! Short and
           | to the point.
        
             | ericswpark wrote:
             | Don't like to see comments like these. I think it violates
             | several HN guidelines, including this one:
             | 
             | > Please don't fulminate. Please don't sneer, including at
             | the rest of the community.
             | 
             | Unfortunately there is no report button.
        
           | ndjxhshgf wrote:
           | Fire alarms are easily fooled-- just cover them with a wet
           | towel. Does that make them bad safety sensors?
        
             | brewtide wrote:
             | Not in their use case, which is the entire "perhaps this is
             | a bad idea" take.
        
             | Rinzler89 wrote:
             | 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.
             | 
             | 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 design phase.
        
               | dylan604 wrote:
               | 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.
        
         | NoahKAndrews wrote:
         | If the point of the sensor is to keep the handle cool, and the
         | wet towel cools the handle, does it really count as tricking
         | it?
        
           | epistasis wrote:
           | 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.
        
             | dylan604 wrote:
             | 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.
        
         | encom wrote:
         | Not a lot. As mentioned in TFA, the chargers are designed to
         | operate in the rain.
        
       | TomatoCo wrote:
       | The article makes it sound like this sensor is only to avoid the
       | handle itself heating up to the point that it would burn the
       | user.
        
         | mitthrowaway2 wrote:
         | 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).
        
       | noodlesUK wrote:
       | I'd be seriously concerned about the risk of water ingress, but I
       | figure it would be much safer to just have a little fan blasting
       | the thing.
        
         | recursive wrote:
         | These things have to run in downpours of rain. A wet towel is
         | nothing.
        
           | OJFord wrote:
           | 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.
        
         | outop wrote:
         | A fan wouldn't cool down a dry plastic handle. Fans cool you
         | down because you are wet and the air flow makes the water on
         | you evaporate a bit quicker.
        
       | pfdietz wrote:
       | All these people being wet blankets on this idea. I'm shocked,
       | shocked.
        
       | mark242 wrote:
       | Do you think it's possible to get the placement of the towel
       | correct if you've gotten your finger chopped off by your
       | Cybertruck?
        
       | trsohmers wrote:
       | This is a lesson that like all good Hitchhikers, you should
       | always carry a towel.
        
         | justahuman74 wrote:
         | OP should have posted this on Towel Day
        
       | renewiltord wrote:
       | 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.
       | 
       | All quite interesting.
        
         | SmellTheGlove wrote:
         | The handle is probably the hottest point. There's a mechanical
         | connection there, so more resistance. At least, I think that's
         | the case.
        
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       (page generated 2024-05-09 23:00 UTC)