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  1. #1

    utility company power

    i was called to a customers house yesterday for a burnt out pool pump, long story short there is 130 volts on each leg of the service what do you guys regard as too much utility company tell me 130 v is ok

  2. #2
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    130V is a bit too high.

    "Electricity is really just organized lightning." George Carlin


    Derék

  3. #3
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    I have never seen it at 130V however I don't think that is what burned out the pump.

  4. #4
    pool guy says pump was set for 220 pump outlet is 220

  5. #5
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    Quote Originally Posted by formula1 View Post
    pool guy says pump was set for 220 pump outlet is 220

    Motors are usually rated for 230V and the receptacle should be rated for 250V.
    "Electricity is really just organized lightning." George Carlin


    Derék

  6. #6
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    Quote Originally Posted by formula1 View Post
    pool guy says pump was set for 220 pump outlet is 220
    Is it 220 or 260? (120 or 130)

  7. #7
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    Quote Originally Posted by Hv&Lv View Post
    Is it 220 or 260? (120 or 130)
    A 260V resi pump motor?
    "Electricity is really just organized lightning." George Carlin


    Derék

  8. #8
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    Quote Originally Posted by formula1 View Post
    i was called to a customers house yesterday for a burnt out pool pump, long story short there is 130 volts on each leg of the service what do you guys regard as too much utility company tell me 130 v is ok
    130V on each leg measured how? Relative to what? Is the voltage at the service to the house phase to ground 130V off of both A and B phase?

    Something is not adding up here.
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  9. #9
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    First off, forget the Line to Ground voltage or even the Line to Neutral voltage, all that matters in this case is the Line to Line voltage. If you have some unrelated issue with your Neutral connection or a difference in ground resistance from the neutral bonding point, that will show up in your L-G reading, But the motor is NOT using the neutral point, so the only thing that matters to it is the L-L voltage level.

    People frequently throw around numbers indiscriminately when it comes to voltage ratings and voltage supplies. Officially (for what that's worth), the "Distribution" voltage for residential installations is 120/240V and officially, the "Utilization" voltage, which is what motor mfrs are supposed to design for, is 115/230V, which allows for some normal voltage drop from the source to the motor connections. NEMA MG-1, the design guide for motor manufacturers, also stipulates that motors should suffer no loss of performance or life expectancy as long as the voltage applied to them is +- 10% of the Utilization voltage. So that means a 230V rated motor can accept anything from 253 to 209V without a problem. That said, there are a lot of old motors out there which were designed before these "official" voltage levels were established, and then because of that, there are numerous lazy / ignorant foreign manufacturers who misread (or don't read) our standards and think that 220V is what we have. It's convenient for them because it makes it so they can sell their motors into places where the frequency is different and they don't have to derate them.

    But... because there are also a lot of 208V installations for which the official Utilization voltage would be 200V, a lot of motor mfrs deal with it by making "208/230V" motors and they provide two separate FLC ratings at those two voltages. But there are no separate winding connections for the different voltages. What they do is design the motor for 220V +-15%. That way they are good for 253 - 200V.

    What's important though is EXACTLY what your motor nameplate says. If it says "208/230V" it will be good to 253V line-to-line. If it says "220V 60Hz" on the nameplate very specifically, it is likely an older motor and it will NOT tolerate more than 242V line-to-line. If it says "220V 50/60Hz" it's likely a piece of Chinese junk.
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  10. #10
    T.M.Haja Sahib Guest
    Quote Originally Posted by formula1 View Post
    i was called to a customers house yesterday for a burnt out pool pump, long story short there is 130 volts on each leg of the service what do you guys regard as too much utility company tell me 130 v is ok
    Increased voltage means increased current and if the pool pump motor was already full loaded,this might cause the motor to be over loaded.So the over load protection to the motor might have tripped the motor.So perhaps the motor burnt out due to defective overload protection?

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