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Why I need change the reference value of an High Potential test depends if is AC/DC?

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    Why I need change the reference value of an High Potential test depends if is AC/DC?

    On a Vaccum interrupters, I need test the dielectric strenght with a High Potencial AC devices, manual of the vaccum bottles say that I need test them with 16kVAC, or, if I got a DC devices, I need test them with 23 kDC.

    Thatís right, because on this test I need check the leakage current on the peak of the sine wave, so, I got two options, inyect a RMS value of 16 kAC, or, multiplies this value per square of two, to get the peak of the sine wave and inject these value (23 kDC) with the high potential devices.

    The question is: Why change the reference from AC to a DC test?, for example, if I test the vaccum bottles with 16 kAC I expect a leakage of current below to 1.3 miliamperes, but if I test the vaccum bottles with 23 kDC I need expect a leakage current below of 5 microamperes. Why change the reference value?

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  3. RabbleRabble is offline Junior Member Pro Subscriber
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    AC V DC

    Quote Originally Posted by Mondaca View Post
    On a Vaccum interrupters, I need test the dielectric strenght with a High Potencial AC devices, manual of the vaccum bottles say that I need test them with 16kVAC, or, if I got a DC devices, I need test them with 23 kDC.

    Thatís right, because on this test I need check the leakage current on the peak of the sine wave, so, I got two options, inyect a RMS value of 16 kAC, or, multiplies this value per square of two, to get the peak of the sine wave and inject these value (23 kDC) with the high potential devices.

    The question is: Why change the reference from AC to a DC test?, for example, if I test the vaccum bottles with 16 kAC I expect a leakage of current below to 1.3 miliamperes, but if I test the vaccum bottles with 23 kDC I need expect a leakage current below of 5 microamperes. Why change the reference value?
    I believe itís because when using AC there is capacitive leakage to consider.

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    Quote Originally Posted by Mondaca View Post
    On a Vaccum interrupters, I need test the dielectric strenght with a High Potencial AC devices, manual of the vaccum bottles say that I need test them with 16kVAC, or, if I got a DC devices, I need test them with 23 kDC.

    Thatís right, because on this test I need check the leakage current on the peak of the sine wave, so, I got two options, inyect a RMS value of 16 kAC, or, multiplies this value per square of two, to get the peak of the sine wave and inject these value (23 kDC) with the high potential devices.

    The question is: Why change the reference from AC to a DC test?, for example, if I test the vaccum bottles with 16 kAC I expect a leakage of current below to 1.3 miliamperes, but if I test the vaccum bottles with 23 kDC I need expect a leakage current below of 5 microamperes. Why change the reference value?
    If I'm not mistaken it has to do with the current flow. In AC the current is going up and down (sinewave) as oppose to DC which current stays at the given amplitude. So with AC there is no "build up" so there isn't as much leakage that is acceptable when compared to DC.

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  7. RabbleRabble is offline Junior Member Pro Subscriber
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    Quote Originally Posted by rmr660 View Post
    If I'm not mistaken it has to do with the current flow. In AC the current is going up and down (sinewave) as oppose to DC which current stays at the given amplitude. So with AC there is no "build up" so there isn't as much leakage that is acceptable when compared to DC.
    The AC valu is in milli Amps the DC is in micro Amps

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