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PSA - check those plugs for discoloring

Discussion in 'Model S: Battery & Charging' started by Electricfan, Jun 4, 2016.

  1. Electricfan

    Electricfan Member

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    I just noticed my plug was a little brown, and took it apart. Wires didn't look so good. This is a 12ga extension cord with ends I put on after replacing the originals. The originals turned brown after a couple of weeks. I made the cable in 2011 for my Chevy Volt. It hasn't been used daily since then, but for the last 5 months or so it has been in daily service, charging the car every night. So, for anybody charging their Tesla on 120V (probably not too many but some), keep an eye on the cables you're using. And for those who will chime in "you shouldn't be using an extension cord", you might be right. But it won't stop people from doing it. extension_cord_plug_burned.JPG
     
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  2. Boatguy

    Boatguy Member

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    #12 wire is certainly sufficient for 12a which is I think all the MS will draw from the supplied 110v/15a adapter.

    The problem I see is not the wire, it's the connection to the socket/outlet/connector. This is frequently the weak link. Too much resistance in that connection caused the wire, and connector to heat up, and the resulting discoloration. Your issue might be best addressed by a higher quality connector or more care in establishing the connection. Nothing wrong with the #12 extension cord wire.
     
  3. TexasEV

    TexasEV Active Member

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    There is a big difference between using an extension cord on rare occasions on a trip, and using it for daily charging.
     
  4. miimura

    miimura Active Member

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    I wasn't going to say it, but I'm guessing that the screws securing those wires to the plug could have and should have been tighter. Proper torque is very important for all screw-down electrical terminations. I would also never use a 120V wall plug that used push-in termination for EV charging.

    Cutting off an inch or two from the end of that cord and re-terminating it with a new socket should be fine. Just make sure the screws are tight.
     
  5. Electricfan

    Electricfan Member

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    This plug didn't have screws. It had little levers that you just clamped down on the wire. I replaced the plug and the new one has screws.

    I also ended up replacing the other end of the extension cord- the male side that plugs into the wall. It didn't look nearly as bad, but the screws (that end did have screws) were loose! I tightened the new one as much as I could. I wonder if they loosen over time for some reason.

    Thanks for all the responses.
     
  6. miimura

    miimura Active Member

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    Heating and cooling due to charge cycles can loosen the screws because of thermal expansion and contraction.
     
  7. deonb

    deonb Active Member

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    For a 12 AWG NEMA 5-15 extension cord? Why not just buy a pre-made one?
     
  8. scottm

    scottm Active Member

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    By the amount of crush on that orange cable jacket, you're over-tightening there.. not necessary.
     
  9. Joeski1

    Joeski1 Member

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    I use an 50' HD 110V extension cord with 14 awg wire when I have to ... it don't get hot at all....even after 10 hours... warm yes.. hot no...
     
  10. Joeski1

    Joeski1 Member

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    most newer homes don't even use a 12 wire in their walls....
     
  11. miimura

    miimura Active Member

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    I'm pretty sure it's crushed like that because it got so hot. A better socket assembly with securely screwed connections would not generate that much heat.
     
  12. Joeski1

    Joeski1 Member

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    I'd also recommend wire brushing or sanding with Emory cloth on those plug contacts so they are nice and shiny... make sure all your contacts and wires are free from corrosion or oxidation.. test with a ohm meter to make sure there is no cross contamination (leakage) between wires on your extension cord... sometimes not enough to set off a standard breaker.. but will click a GFI..
     
  13. TexasEV

    TexasEV Active Member

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    But they don't have runs of 100 feet either.
     
  14. davewill

    davewill Member

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    Sound advice, and it doesn't have to be a 120v extension cord to have a problem. I think I'll open up the box and check the 6-50 my EVSE plugs into. For that matter take the EVSE's cover off and look at the internal connections, too. Certainly can't hurt to inspect occasionally, especially when it gets used at high amperage every night.
     
  15. scottm

    scottm Active Member

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    And they are one solid copper conductor. Not stranded.
     
  16. Joeski1

    Joeski1 Member

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    Hey Tesla says NOT to use one at all...... this guy coulda burnt his home down to get $10 worth of charge to his vehicle... I got a 240V 50amp hookup @ my place.... only use that 110 V cord here and there.. and have never had any meltdown like that guys has photographed while using it..... could always try buying an extension cord with solid wire... Good Luck...
     

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