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Scary issue with Nema 14-50 adapter melting

Discussion in 'Model S: Battery & Charging' started by robertmgarrett, Oct 29, 2013.

  1. robertmgarrett

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    Had a very disturbing incident last night. My Model S was charging in my garage when my smoke detector went off. I ran to the garage and saw plumes of smoke coming from the Tesla Nema 14-50 adapter. The car was still charging! I unplugged the charger from the car and yanked the charger adapter plug from the outlet. The Nema 14-50 adapter fused to cord. The adapter had a hole on one side where it was melting. I called Tesla and they sent out someone with a new mobile charger and nema 14-50 adapter. I am not sure how i feel about using this adapter again. The breaker never tripped nor did the car generate any error or shut off charging. I had the electrician come out and inspect the outlet. It showed no signs of charring and tested out fine for constant voltage within specs. Not sure how I feel about Tesla's response at this point. I plan on calling them in the morning.


    I just felt like i should post this to make others aware. Hopefully this was just a case of bad luck in getting a bad adapter
    .

    Rob

    IMG_0206.JPG
     
  2. fcharland

    fcharland Member

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    #2 fcharland, Oct 29, 2013
    Last edited by a moderator: Oct 29, 2013
    have you checked the breaker? This is the device that should have tripped when too many amps go through...
     
  3. yobigd20

    yobigd20 Well-Known Member

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    #3 yobigd20, Oct 29, 2013
    Last edited by a moderator: Oct 29, 2013
    There's actually many of us that have had this same issue, including myself. If the adapter is not snugly snapped into the UMC and there is a slight gap, this will happen.

    I know Tesla was replacing early adapters for everyone for free due to this issue. Problem is that mine happened with the "new style" adapter so I'm not convinced that the issue is resolved at all. Haven't had any issues since my adapter and UMC was replaced, but I always make sure that the adapter is firmly locked into the UMC now.
     
  4. yobigd20

    yobigd20 Well-Known Member

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    Btw, I can tell from that photo that the adapter is not firmly locked into the UMC , and that is exactly why this melted.
     
    • Informative x 1
  5. mnx

    mnx 2013 P85

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    Many others have had this issue (the adapter getting hot and/or melting). I already knew of the issue (there is already another long thread about it), so when I went to unplug my adapter from the wall and felt it was scorching hot I called for a replacement.
     
  6. robertmgarrett

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    --It is not firmly locked now because the Tesla folks asked me to see if I could pull it apart once it cooled down.
    --no breakers tripped nor did car stop charging. I had electrician come out and stood over his shoulder. All looks pristine in the wiring.
    --Love Tesla & my cat but this is a dumb issue...really you have to make sure it is perfectly snug or maybe burn your house down? Seriously! I have money invested in this company. Can you imagine the bad press of a house fire. This really should be addressed ASAP.
     
  7. RandyS

    RandyS Fan of Elon

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    To me, those pins where the adapter meets the charger cable are quite small for continuous 40 amp current flow day in and day out. Not to mention how hot the inline "box" gets at that level of charging. My UMC stays in the trunk for occasional use and I use a wall mounted hard-wired EVSE for everyday charging.

    If you are going to use the mobile connector to charge every day, I would suggest dialing down the current flow just a little bit on the screen to 25 amps or so to reduce heating effects...I know a lot of people are successfully using these every night to charge, but this isn't the first time we've seen melting in the adapter area. I think its easy to take for granted the fact that almost 10,000 watts can flow through that small device and connector / adapter...
     
  8. mknox

    mknox Well-Known Member

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    Likely too many amps didn't go through the breaker. A loose connection at the UMC to adapter connection would act just like a heater element.
     
    • Like x 1
  9. Zythryn

    Zythryn MS 70D, MX 90D

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    We have been charging about 26,000 miles on two different UMCs (two cars) with no issues.

    While I certainly appreciate your concern, when dealing with any high current device you need to make sure the connections are solid and any adapters are properly seated.

    As for your concern about how TESLA dealt with the situation, they immediately came out and replaced the UMC? What better response response would you like? I have never had another car company respond nearly that well.
     
    • Like x 1
  10. robertmgarrett

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    RoverS- You realize most reputable electricians have 24X7 emergency service. So I called them. Really not too hard. BTW...this is your 3rd post...so what is your motivation.

    Zythryn-You ask a fair question. Based on this forum and Tesla's forum along with response to my initial posts this has been an ongoing issue. We all saw the press frenzy from the car fire. Can you imagine what happens if a house were to burn down? I personally just want peace of mind for the safety of my family. So I will press this with Tesla to determine what is going on with these adapters. I have given my melted one to them to study.

    I love Tesla and my car. A stupid little adapter should not be allowed to be the cause of issues this serious. Think about how many issues have been reported just in this forum based on (in the manufacturing world) the small number of adapters in use residentially. This seems like an issue Tesla should proactively address to protect themselves from these type of incidents and the fallout that comes from them.
     
  11. efusco

    efusco Moderator - Model S & X forums

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    The OP need not be challenged here and it's smart to be aware. This isn't the first time we've seen issues with that connector melting and is certainly something to take back to Tesla for consideration of design improvements. As pointed out, a house burning down due to a faulty connector today, a hotel fire tomorrow and now not only are investors concerned, so are potential buyers, and other hotels/facilities that might now reconsider plans to install EV chargers of any type.

    It is important to aggressively and seriously address issues like this when they come up...and please quit with the snipiness...this is a new high that a guy with one prior post calls the guy with a relevant and factual post a troll...amazing.
     
  12. Zythryn

    Zythryn MS 70D, MX 90D

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    I agree with you completely, and I am happy that they have the adapter in question so they can study what happened and make any improvements if possible.
    Likewise, I hope you will take extra care to also seat the adapters properly to prevent this type of thing from happening.

    Tesla should not be blamed if the adapter was improperly seated. Likewise, you should not be blamed if the adapter was bad.
     
  13. mknox

    mknox Well-Known Member

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    Absolutely! I continue to be amazed at how "small" the connectors and adapters are for this car considering the amount of continuous current it can draw. The cables and connectors on stoves and dryers seem much more robust and they only carry intermittent loads. Having said that, these devices (presumably) do have all the necessary UL / CSA approvals, so hopefully these incidents are just anomalies that Tesla seems to be dealing with well.
     
  14. qwk

    qwk Model S P2681

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    Spot on. This is exactly what happens.
     
  15. robertmgarrett

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    --The adapter was seated properly. In the pic it may not look like it because the Tesla folks asked me to see if could pull it apart after it cooled down.

    --I respect your opinion on the seating of the adapter but disagree. You can not go to mass market one day and hope folks will be always do things the 100% correct way to prevent such an issue. It needs to be engineered in such a fashion to mitigate that risk as much as humanly possible. Or if not possible eliminate that as a recommended way to charge the vehicle.
     
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  16. qwk

    qwk Model S P2681

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    Having myself melted one of these a bit, and putting almost 4MW of power through another one at 40A with no issues(now I always double check to make sure its seated), and having multiple talks with a head tech that deals with this on a daily basis about the issue, I'm sure that a gap between the adapter/socket is the cause for these problems.
     
  17. mknox

    mknox Well-Known Member

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    I too check mine frequently, and even bought a temperature "gun" to keep an eye on things. So far, I have had no problems, but I do charge at a reduced rate. After reading some of the earlier threads on this subject, I closely inspected my cable to adapter interface. With mine, it doesn't seem possible for it to be seated improperly... either it's clicked into place or it's not. I think it's entirely possible that the OP's cable had a defect, and it seems that Tesla jumped right on it and got it fixed. Manufacturing flaws do exist. I'm on my third UMC. Not for heating but because the first two gave intermittent problems connecting to the car. We have to expect some issues, and as long as Tesla stands up for their products we will all be fine.
     
  18. efusco

    efusco Moderator - Model S & X forums

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    I disagree a bit here. Tesla should design the adapter such that it is either properly seated, or won't work. If the locking mechanism needs to be redesigned, then so be it, but while convenience of switching b/w adapters was clearly a priority, so should safety be a high priority, there should be a clear distinction between fully seated and not seated, no gray area.
     
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  19. rabar10

    rabar10 FFE until Model 3

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    RE: system design -- I would think there's a way to integrate one or more thermistors into the J1772 signalling circuitry, so that if the temperature on/near either the adapter contacts or the plug blades gets too hot, the car stops charging...
     
  20. gg_got_a_tesla

    gg_got_a_tesla Model S: VIN P65513, Model 3 Res Holder

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    My original UMC from back in January fused with the 5-15 110V adapter (it did that gradually over a couple of months of usage as it progressively got harder to uncouple it from the cable).

    Something Tesla should avoid for sure with the otherwise-very-convenient UMC-adapter design.
     

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