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66.3v power?

Discussion in 'Off Topic' started by Zextraterrestrial, Aug 15, 2013.

  1. Zextraterrestrial

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    #1 Zextraterrestrial, Aug 15, 2013
    Last edited: Aug 16, 2013
    Our house power, and the rest of the neighborhood just dropped to 66V per phase. Is this a brownout?:scared:
    I could make a 120 if I needed to charge badly.

    What causes this type of
    grid failure? Natty gas gens up in Humboldt I think

    Led lights are cool.

    ..so it lasted almost an hour. Some stuff works at 66V other stuff doesn't. It is kind of interesting. Some fluorescent lights work, others don't. Small fridge worked but not the big one. Still haven't heard what happened but our cable internet isn't working now so maybe someone crashed? I would think that would make no power though
     
  2. MichaelS

    MichaelS Member

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    Yes, that is a brownout. Capacitive start motors can burn out at that voltage because there is not enough voltage to spin them up. Most electronics will survive, but may not operate properly. Probably should unplug everything until the voltage comes back up because you don't know if it will spike while it's being fixed.

    Don't know for sure what would cause that but a partially damaged transformer with an open winding could do that. If one side of the 240V gives out, the good 120 can bleed back to the other side through loads connected across the 240V.
     
  3. Lloyd

    Lloyd Active Member

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    Best thing to do is to turn off your main breaker until the issue is repaired.
     
  4. FlasherZ

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

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    It depends, there are a lot of things that can cause it - turbine failure; high resistance in transmission lines causing significant voltage drop; partial winding burn-through through in a transformer; the list goes on and on.

    Best solution as noted is to shut your main off, or shut everything else off and limit power to lighting circuits only. Some motors will burn up if the voltage isn't enough to start them or will generate too much heat. Many A/C units and refrigerators will refuse to start and will protect themselves.
     
  5. Zextraterrestrial

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    cool, seemed strange. lasted for about 50 minutes and nothing seems damaged. I never checked to see if each phase was the same for bleeding of a single phase across, makes sense though 66 is half of our 'normal' voltage

    thanks
     
  6. FlasherZ

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

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    Yeah, a neighborhood bad neutral is a nasty thing and can cause one leg to go 66V while the other leg goes to 174V. Half your house goes "POW! POP!" while half your house dims... I've seen it happen, and I've also seen a power company have to replace a shedload of appliances because their negligence caused it by floating the neutral.
     

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