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Electrical hum/buzz around 50A and higher

Discussion in 'Model S: Battery & Charging' started by MarcG, Mar 10, 2017.

  1. MarcG

    MarcG Active Member

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    I just had a Tesla HPWC installed on an 80A circuit (max charge rate = 64A), and I'm noticing a hum around my electric service panel area whenever the current draw is around 50A and higher.

    It seems to go away completely below 48A, but around 50A it starts to get noticeable then gets louder and louder as it goes up to 64A.

    Has anyone experienced this, and can point to what the problem could be (if any)?
     
  2. Brass Guy

    Brass Guy Member

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    This happened to me with a 14-50 install. It buzzed anywhere near 40A. In my case it was the main breaker, which was 100A and probably over 25 years old. It started heating up too; that's dangerous. I'd bet in your case it's the new breaker. That's not unheard of.
     
  3. tga

    tga Supporting Member

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    I just installed a new 30A breaker that intermittently buzzes @ 24A. I wouldn't worry about it, as long as nothing gets hot (warm is normal when at 80% of rating). If you can hold your hand on the breaker indefinitely, that's not hot.
     
  4. brkaus

    brkaus Active Member

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    I installed new 50a breaker and it buzzed. After about 30min it got quite hot. New one was quiet and cool.

    I'd have it checked. And wouldn't wait too long.
     
  5. MarcG

    MarcG Active Member

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    Thanks for the replies guys, I'll get it checked out.
    The electrician installed a new 80A breaker just after upgrading the main service panel to 100A. I'll find out if they can swap it out.
     
  6. Brass Guy

    Brass Guy Member

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    Whoa, upgrading the main panel to 100A? I figured you had at least a 200A panel to add a breaker larger than 50A. There must not be much else in there. Anyway, have it checked out because it could be either new breaker.
     
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  7. AWDtsla

    AWDtsla Active Member

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    This pixies are getting angry.
     
  8. MarcG

    MarcG Active Member

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    Yeah the service panel only serves the garage. There are only a couple of outlets and a few lights on this meter. The rest of the house is on a different meter. So 100A for my garage's main service panel, 80A for the HPWC, and 20A for the lights and outlets.
     

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