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HPWC Wiring: Is conduit required in crawlspace?

Discussion in 'Model X: Battery & Charging' started by ctn531, Aug 10, 2018.

  1. ctn531

    ctn531 Member

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    Between my breaker panel and my garage there is a 40' run of crawlspace. I have a 90A breaker and 2AWG wire running to my HPWC. I will use conduit for the run in the garage leading up to the HPWC. But how about inside the crawlspace (between my breaker panel and garage)? Is conduit required? The wire is THHN.

    Thanks!
     
  2. P85_DA

    P85_DA Supporting Member

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    Yes u need conduit for THHN
     
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  3. posity

    posity Member

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    Yes, THHN MUST be run in raceway (conduit).
     
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  4. ctn531

    ctn531 Member

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    Thanks for your help guys. Spent most of the day today running the 2AWG in conduit. I've run the section from the breaker to the 100A safety switch in the garage - now I just need to get my hands on a HPWC (and also my car for that matter) - today is 6-weeks exactly. Looking like it is going to be 9-10 weeks. Oh well, all good things come in time.

    Thanks again for the advice!
     
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  5. posity

    posity Member

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    There is also a 'conduit fill' requirement that specifies the size of the conduit vs. the size of all the wires. Basically amounts to: if the conduit is more than around 50% full with wire, your conduit is too small. More complicated than that: you have to look it up. Really easy to forget a wire when calculating, then have to upsize the conduit. Oops.
     
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  6. Cosmacelf

    Cosmacelf Well-Known Member

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    Here’s a chart that shows this. You need a 1” conduit for 3 such conductors. conduit fill table - Google Search:
     
  7. essmd

    essmd Phantom X

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    The really truthful answer to this question depends on whether or not you plan to pull a permit thus require an inspection by your local government and/or prefer to install it to current electrical codes.

    If you DIY, and don't plan on anyone ever seeing what is in the crawlspace, then running your wires in a conduit is your choice.

    The argument against conduit is heat, which will be generated in high power delivery and be retained in the conduit.

    Also, it may depend on the crawlspace layout, note that conduit is not required in the space behind the drywall.

    However, if you go to sell your house with the HPWC still installed, a sharp home inspector should call that out, but it's possible may go unnoticed.

    Also, should you ever have a fire in your home, whether or not related to your HPWC install, Homeowners' Insurance may deny your claim if they notice that.

    For you it is done, but other"s may want to check with local codes, which I suspect requires conduit, as I did for both garage attic and drywall surface mount to get the permit.
     
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  8. davewill

    davewill Member

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    Using that logic, he could just solder a bunch of old coat hangers together.
     
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  9. jboy210

    jboy210 Supporting Member

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    Seems like there are more than enough issues to do things the legal way, and with a permit and inspections.

    We had a guy build a pergola without a permit by me. Put a nice outside kitchen as part of it. When he went to sell the house the buyer went to look up the permit for it. No permit and it triggered an inspection. City said structure was too close to a fence and had to be torn down. The buyer walked because of concerns that there might be other undisclosed improper construction projects.
     
  10. tpham07

    tpham07 Active Member

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    legally yes.

    strictly speaking, no. A conduit is meant to protect the wires from being gnawed on by creatures that might live in your house. exposed wires & insulation = fire risk.
     
  11. gilscales

    gilscales Member

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    A roll of tinfoil is way easier, no solder required!
     
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