This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Microshocks from induced voltage

Has anyone ever come across the requirement to earth a section of metallic fence to mitigate micro-shocks that may be induced by an overhead transmission line? I have looked online but there is no methodology or guidance value listed other than just "earth the fence".


Any info would be useful.


Thanks

Mike
Parents
  • if your only problem is the capacitive coupling then you will be looking at a few k ohms per kilometer is all that will be needed to pull it  down to 60V RMS.

    For that a meat skewer in the flower bed with bell wire would do.

    However, for good mechanical reasons, and to survice a bit of weather, a proper electrode and a sensible wire diameter will be needed, or a metal fence  post in every 10th position or something.

    I am very well aware that neither BS7671, nor the railway rules, correctly handle the case of things that only need to be loosely earthed, and tend to specify every thing as if hundreds of amps may flow, when the series impedance means it simply cannot.
Reply
  • if your only problem is the capacitive coupling then you will be looking at a few k ohms per kilometer is all that will be needed to pull it  down to 60V RMS.

    For that a meat skewer in the flower bed with bell wire would do.

    However, for good mechanical reasons, and to survice a bit of weather, a proper electrode and a sensible wire diameter will be needed, or a metal fence  post in every 10th position or something.

    I am very well aware that neither BS7671, nor the railway rules, correctly handle the case of things that only need to be loosely earthed, and tend to specify every thing as if hundreds of amps may flow, when the series impedance means it simply cannot.
Children
No Data