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IEC 60364 Table 48A

Former Community Member
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Does anyone know where I can find table 48A? I am reading of its existence, but don't know where to find it.
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  • 0
    ProMbrooke:



    Personally, I think there needs to be less focus on earthing and bonding, and more on loop impedance.




    That's interesting. There will be less control of touch voltage. Loop impedances in TN-S systems are typically higher than TN-C-S.


    With microgeneration and other forms of network stability control that are necessary for embedded generation in the move to DSO, effective loop impedance can change. In addition, taking an accurate earth fault loop impedance reading will become a near impossibility ... and perhaps meaningless.


    Guidance already advises a check of Ze only to confirm an external earth connection for supplies to  - otherwise, assume Ipf = 16 kA / Ze = 0.35 Ohm (TN-C-S) or 0.8 Ohm (TN-S).



    What precisely are you advocating?


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  • 0
    ProMbrooke:



    Personally, I think there needs to be less focus on earthing and bonding, and more on loop impedance.




    That's interesting. There will be less control of touch voltage. Loop impedances in TN-S systems are typically higher than TN-C-S.


    With microgeneration and other forms of network stability control that are necessary for embedded generation in the move to DSO, effective loop impedance can change. In addition, taking an accurate earth fault loop impedance reading will become a near impossibility ... and perhaps meaningless.


    Guidance already advises a check of Ze only to confirm an external earth connection for supplies to  - otherwise, assume Ipf = 16 kA / Ze = 0.35 Ohm (TN-C-S) or 0.8 Ohm (TN-S).



    What precisely are you advocating?


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