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Is fuseable link resettable in new 14-50 adapter?

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I don't think anyone knows, I haven't seen if any have been sawed open. Would you like to be the first to find out? Loosen a screw on your 14-50's wire and give 'er a whirl at 40A. :)
 
Oh wow, good thing I didn't try to test it! Just got a call from Tesla saying that a thermal fuse was an earlier concept, but in the end they ended up just using high temperature materials, better welds, and the firmware update to "solve" their issue. So, no thermal fuse at all.
 
Oh wow, good thing I didn't try to test it! Just got a call from Tesla saying that a thermal fuse was an earlier concept, but in the end they ended up just using high temperature materials, better welds, and the firmware update to "solve" their issue. So, no thermal fuse at all.

Hmmm, I am not surprised. I suggested earlier that the light grey material was a different and presumably higher-temperature plastic, but was shouted down on another thread at the time. :wink:
 
Oh wow, good thing I didn't try to test it! Just got a call from Tesla saying that a thermal fuse was an earlier concept, but in the end they ended up just using high temperature materials, better welds, and the firmware update to "solve" their issue. So, no thermal fuse at all.

I guess this is correct. Tesla filed an updated remedy plan with the NHTSA on February 24th:

http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM454956/RCDNN-14V006-7510.pdf

During final validation testing of the new design, the NEMA 14-50 adapter with internal thermal fuse was not any more robust than the original NEMA 14-50 adapter it was intended to replace. Accordingly, Tesla turned to an alternate replacement NEMA 14-50 adapter that was concurrently being developed. The alternate replacement adapter utilizes different internal material as well as a different weld process between wires and pins that result in a NEMA 14-50 adapter that is more tolerant to higher temperatures and less likely to degrade than the either the suspect NEMA 14-50 adapters or the originally proposed replacement.

Too bad. It seemed like a thermal fuse would mitigate against problems with the receptacle, but this won't.
 
Well no, the new plastic and better welds should make sure that adapters don't melt. And then you have the firmware changes that reduce charging current.

Actually, I haven't heard about an adapter melting issue for a while now...

Hmmm, I hope you are right about this but my instincts say that, over time, wear will cause heating. Perhaps the new plastic will withstand higher temps but there are limits. I really liked the idea of a fuse as that would be far safer.
 
I know that there are many others who dislike this idea, but I think the car's greater intelligence about the charging conditions is what's going to make the biggest difference here. Hotter plastics are good, but the car automatically backing down the current will play a big part in ensuring the cords don't melt.
 
Hmmm, I hope you are right about this but my instincts say that, over time, wear will cause heating. Perhaps the new plastic will withstand higher temps but there are limits. I really liked the idea of a fuse as that would be far safer.

According to what Tesla told the regulator in a letter, they tested both the fused adapter and the one without a fuse and found that the fused one didn't help at all.
 
According to what Tesla told the regulator in a letter, they tested both the fused adapter and the one without a fuse and found that the fused one didn't help at all.

That's because there isn't much they can do to improve the adapter. The problem is also in the UMC end. Cutting off the adapter and using a male 14-50 plug eliminates most of the problems. I'm guessing that Tesla doesn't want to take on the expense of replacing the UMC with a new design due to cost, which is fine except for the fact that they are still using the crappy design. If something sucks, the last thing that should be done is make more of it.
 
That's because there isn't much they can do to improve the adapter. The problem is also in the UMC end. Cutting off the adapter and using a male 14-50 plug eliminates most of the problems. I'm guessing that Tesla doesn't want to take on the expense of replacing the UMC with a new design due to cost, which is fine except for the fact that they are still using the crappy design. If something sucks, the last thing that should be done is make more of it.

There are only some limited options, and the issue seems confined to the 50A adapters; throwing the entire design out is throwing the baby out with the bath water.

Cutting off the adapter also makes the UMC impossible to use with 6-50's, 14-30's, 5-15's, 5-20's, among the other options we have. I think Tesla should have switched to something like a UMC2 with bigger pin surface area that would be subject to less heat once the issues were determined. We saw early clues that the design was bad, and if they had made a design decision then, far less people would have been affected.

That said, I would still take this design over the one-cord-for-each-outlet design, or a pure J1772 design.

(For what it's worth, the car end of my HPWC is beginning to get hot to the touch again while charging @ 80A. The cord's been replaced once for the same issue. Wonder if we're going to need a contact cleaning kit, or if the valets/porters will be sent to clean/inspect the contacts for those customers who have them.)
 
I know that there are many others who dislike this idea, but I think the car's greater intelligence about the charging conditions is what's going to make the biggest difference here. Hotter plastics are good, but the car automatically backing down the current will play a big part in ensuring the cords don't melt.

I agree that there is some benefit to intelligent charge monitoring but I remain skeptical that sw can detect a problem with 100% accuracy. I'd love to hear the theory behind what they are doing though won't hold my breath.
 
...I think Tesla should have switched to something like a UMC2 with bigger pin surface area that would be subject to less heat once the issues were determined. We saw early clues that the design was bad, and if they had made a design decision then, far less people would have been affected....
Yes, compared to the blade sizes for the 14-50, the Tesla pins look minute. Are these tiny pin connections subject to any NEC requirements? Wonder what UL would say if they had to certify? Even the J1772 pins seem too small to me, although I suppose there is more surface area than meets the eye due to the male/female mating surfaces.
 
Yes, compared to the blade sizes for the 14-50, the Tesla pins look minute. Are these tiny pin connections subject to any NEC requirements? Wonder what UL would say if they had to certify? Even the J1772 pins seem too small to me, although I suppose there is more surface area than meets the eye due to the male/female mating surfaces.

Nope, it's an appliance, subject only to listing requirements if they want to have it listed.