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NEMA 14-50 Permanent Extension

Discussion in 'Model S: Battery & Charging' started by olanmills, Apr 26, 2016.

  1. olanmills

    olanmills Member

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    I am trying to figure out what options there for permanently extending a NEMA 14-50 outlet. I found this (Heavy-duty NEMA 14-50 extension cord for Tesla, 20 ft.) on the forums, but I don't think that's going to be long enough.

    Back in 2012, I had a NEMA 14-50 installed in my parent's third car spage in the garage so I could charge when visiting, if necessary. Now my dad has a Model X coming in May. The third car space is kind of tight, and also, to make matters worse, if you park head-in, the outlet is on the passenger side.

    What I wanted to do is maybe have some kind of long extension cord solution where we run the extension cord up the wall and along the ceiling, and then maybe have it hang down between the first and second parking spaces and from there, we could plug in the Tesla mobile adapter. Maybe if we get fancy, we could have the cord be retractable.

    What are the options here? Or is the only option to have a professional electrician do it? I am worried that that would cost a lot.

    I also reserved a Model 3 for my mom, so eventually, we'll probably need to get a HPWC or something, but we got two years to think about that.
     
  2. AEdennis

    AEdennis Active Member

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    If you have space in the panel, why not just install additional NEMA 14-50 outlets?

    We have 2 NEMA 14-50, 1 NEMA 6-50, and a J1772 in our garage and driveway.
     
  3. brkaus

    brkaus Member

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    You could add the additional 14-50 as mentioned above. Probably the best choice if your planning on another electric vehicle in the future and you have the capacity. If your OK with surface conduit it wouldn't be that expensive I don't believe.

    You could have an electrician extend the outlet, possibly putting a panel in the location of your current 14-50.

    If you switch to a HWPC, later you could connect two of the new load balancing type off the panel. Breaker size depending on what wire size they used for the 14-50.
     
  4. olanmills

    olanmills Member

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    I might not have been clear, but the existing NEMA 14-50 outlet is next to the panel, and this is not near the location where we would like to park the Model X.

    Maybe we could have a surface conduit go all the way to the other side of garage and put an outlet on the opposite wall, but eventually, if we also get the Model 3, it would be nice to some how be able to charge from some kind of outlet in the middle of the garage, where there is no wall, which is why I was talking about having a cable/outlet hang down from the ceiling
     
  5. Cyclone

    Cyclone Active Member

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    What kind of distance are you talking about? And do you have room in the panel? Perhaps wiring in an HPWC with a 24' cord somewhere in between the other two bays would be the solution?
     
  6. pchilds

    pchilds Member

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    For safety reasons, extension cords are not for permanent use. It is best to Install a new 14-50.
     
  7. FlatSix911

    FlatSix911 918 Hybrid

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    Here is some good advice from the Forum FAQ: Home Tesla charging infrastructure Q&A

    CAN I USE AN EXTENSION CORD?

    Tesla Motors makes it clear that an extension cord is not to be used with its UMC. The NEC requires that you follow manufacturer’s instructions, so technically you violate the NEC by using one. The NEC contains some rules for using extension cords. Some of the rules state that extension cords are not permitted to be used as a substitute for the fixed wiring of a structure; run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors; run through doorways, windows, or similar openings; or be concealed behind building walls, structural ceilings, suspended ceilings, dropped ceilings, or floors.

    However, as to the question of whether it is safe or not… Technically, yes. With the right size conductors, an extension cord, whether 120V or 240V, is relatively safe in limited lengths. For 120V, to keep the voltage drop within range, you can use a 14 AWG cord if your TOTAL one-way circuit length from the car to the breaker panel is < 50 ft., 12 AWG if your total is < 100 ft., and you'd need to go to 10 AWG if you're at 150 ft. or greater.
    • For 40A charging @ 240V (NEMA 6-50, 10-50, or 14-50), you should use 6 AWG, and your total one-way circuit length can be 300 ft, with voltage drop at reasonable levels.
    • For 24A charging @ 240V (NEMA 6-30, 10-30, or 14-30), AWG 10 is good to 200 ft. one-way from breaker panel to the car, go one gauge up (AWG 8) if you need more.

      As mentioned, keep your cord to the smallest length possible to reduce voltage drop and increase your charging efficiency. Keep in mind the potential insurance implications of this, as mentioned above. You are violating the NEC in the US by doing this.
     
    • Helpful x 1
  8. FlatSix911

    FlatSix911 918 Hybrid

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    • Helpful x 1
  9. smsprague

    smsprague Member

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    Amazon has NEMA 14-50 extension cords with 6 Guage wire in 25, 30 or 50 foot lengths. Search "nema 14-50 extension cord" on Amazon. I have a 25 footer in my Frunk, has come I. Handy a few times.
     
  10. brkaus

    brkaus Member

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    Sorry, I missed the hanging part. There have been a few threads here and I believe I saw an ad for a swing down charger. Can't find it now though.

    Perhaps a 24' HPWC and a bungee cord or two?
     
  11. olanmills

    olanmills Member

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    Thanks for the helpful advice. Yeah, I should take some measurements, but my guess is that a straight line distance across the floor from the outlet (which is on the far right side of the garage, at the third card spot, where the X will not easily fit) to the charging port to a car parked in the middle space would be about 15', and if it was parked in the first spot on the far left, it would probably be about 23'. However, if we were to go up the wall and across the ceiling and back down, it would probably be about 10-20' extra in either case.
     
  12. TexasEV

    TexasEV Active Member

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    This is not helpful. Everyone know 14-50 extension cords exist. The consensus is they're for use when traveling when you have no good alternative. The responsible answer is an extension cord is NOT a permanent solution for your garage.
     
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    • Informative x 1
  13. rypalmer

    rypalmer Member

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  14. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

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    Everyone has covered my thoughts. If I were attempting to permanently extend, I would probably remove the existing receptacle, use proper box covers to attach surface mount conduit, and surface mount a new box where required using the old receptacle (or a new one). A little more costly than stapling a cord to the wall, but significantly safer and protected from damage, as well as code-compliant.
     
    • Helpful x 1
  15. ChrisPDX

    ChrisPDX Member

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    Does anybody know if there are requirements that the new HPWC be mounted on a vertical surface? If not, maybe mount them on the ceiling. Simply rerun the existing 50amp circuit through outside conduit along the ceiling to right above where the charging ports would be. You can daisy chain multiple HPWCs to each location. Assuming the ceiling isn't too high, the 8.5" cord should be long enough to just hang down and plug right into the car. Assuming both cars don't drive an average of 300 miles total or more per day, a 50 amp circuit shared between both cars should be adequate.
     
    • Helpful x 1

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