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HPWC retrofit calamity

Discussion in 'Model S' started by Xd85, Jul 13, 2020.

  1. Xd85

    Xd85 Member

    Joined:
    Oct 20, 2017
    Messages:
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    Location:
    Central Ohio
    Just did a DIY retrofit over a 14-50 installed by my house builder. The old outlet had A 6/3 romex run to a receptacle stapled to a stud. (No drywall on, no conduit)

    I placed the HPWC on the same stud for cable bottom entry.

    How do you seal where the romex enters the unit? 6/3 leaves a bunch of room.

    ive read to cap off the neutral inside the HPWC but doesn’t seem to be enough room for a bulky wire but. Has anybody done this? So far electrical tape the ends but hoping for more legit solution.

    finally, the screw that secured the ground I somehow stripped but replaced with a regular zinc plated machine screw that electrically works. Looking for some expertise with this.

    Yeah next time I’d probably hire somebody. :eek:
     
  2. paulk

    paulk Member

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    Location:
    hartford, ct
    you can buy a clamp connector at home depot (search the site for 100113541) and have the 6/3 pass through it into the HPWC. that part number is for a 1 inch opening which is i think the right size.

    no worries about replacing the screw. a regular steel machine screw should be fine.

    as for the neutral wire, its not carrying any current and really has no purpose. you can cut it short or be creative about stuffing it somewhere and taping it. the only reason to keep it is if you replace the HPWC in the future with something that might need it. if you keep the wire its best to not strip the end and tape the tip.
     
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  3. brkaus

    brkaus Well-Known Member

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    Not sure if there is a standard, but I’d put a wire nut and then electrical tape on the unused wire.
     
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  4. murphyS90D

    murphyS90D Member

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    Location:
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    Install a 100 amp sub-panel and run the existing wire to it. Run the proper wire, without a neutral, from the sub-panel to the HPWC.
     
  5. ucmndd

    ucmndd Well-Known Member

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    Why would you feed a 100 amp sub panel with 50 amp wire, just to avoid wrapping some electrical tape around the existing neutral?
     
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  6. Battpower

    Battpower Supporting Member

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    @Xd85, your calamities don't sound nearly as dramatic as mine!
     
  7. 1windy

    1windy Member

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    I'm with you. Safer and leaves you options. Doesn't have to be 100 amp could be less. What is important is the breaker size feeding it. As the HPWC will unlikely be used 24/7 gives you the option of adding a receptacle in the garage for say a vacuum.
    Also make sure the wire connections are tight and stay tight. Loose wires cause arcing and fires especially neutral wires. They become loose by heating and cooling.
    Good luck
     
  8. brkaus

    brkaus Well-Known Member

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    What is important is the wiring size. A breaker is easy to change. It was stated that it's 6ga Romex which I believe is good for 50a in most conditions.

    To me it would be easiest to tap an existing 120v outlet to add another 120v.
     
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  9. 1windy

    1windy Member

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    Not seeing the existing layout and number of existing receptacles it is impossible to say what is easiest but I agree.
     
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  10. Pluturi

    Pluturi Member

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    Location:
    Upstate NY
    Just want to reinforce this comment. What you’ve done is fine as long as you leave the 50A breaker in place and ensure that the HPWC only supplies 40A to the car. The #6 Romex you have does not support the 48A charging capability of the HPWC.
     
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  11. Xd85

    Xd85 Member

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    Location:
    Central Ohio
    Thanks all. Another trip to Home Depot solved it well. Got the clamp per @paulk to minimize space around entry. Took it down and took a wire nut to cap off the neutral and wrapped it well with electrical tape and fed the whole assembly into the HPWC box.

    @1windy house builders for some reason declined to pre wire a circuit and said it must have a receptacle. So I got 2 already. One is exposed on the unfinished wall so I took this project on. Guess I was a little late to the party to request a 6-50 to eliminate the neutral problem.
     
  12. cmghoughton

    cmghoughton Member

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    Oct 23, 2019
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    Location:
    Lake George
    I just upgraded my 14-50 plug to a Gen3 wall connector and left the neutral wire coiled up neatly inside the new body of the charger. I followed the bottom entry mount and the new Gen3 leaves a good amount of space for what looks like this wire and has a perfect wire channel for the heavy gauge wire. No crazy bending and struggling. I would cap that wire off with a nut or something just for piece of mind.
     

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