Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 45 replies
  • Subscribers 32 subscribers
  • Views 4034 views
  • Users 0 members are here
Options
You may also be interested in
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

Cattle deaths

lyledunn
Some 10 prize bullocks died in quick succession whilst housed over winter in a cattle shed. The government vet was unable to reach a conclusion on cause but apparently does not discount electric shock as an indirect cause. 

The shed comprises steel columns and trusses with corrugated iron sheeting over. The floor comprises re-Inforced concrete slats over the slurry tank. The pens have steel barriers supported by steel posts all of which are heavily corroded but still making contact with other albeit fortuitously.

The earthing system is TT with the shed steelwork on its own providing a substantially low impedance of 5 ohms using a loop tester. A 100mA RCD protects the rather ropey lighting circuits.defccf32df3c757507a0db6ad0a35f87-huge-a5af3537-8eae-4a3c-9126-68fa60b61ac7.jpg

whilst the floor could be wet, I can’t conceive how a voltage difference could be established even if the steelwork was at 230v

Parents
  • 0

    Sparkingchip:

    ...

    The diagram in this article suggests there can be the full voltage gradient 230 volts to zero across a cow on soil.

     




    The figure is rather simplified but is about right for a rod of say 1m to 1.5m length - half the voltage drop is in a circle of radius more or less equal to the rod length (all sorts of assumptions about uniform soil density and no wet or dry  patches or buried rocks are hidden- in reality the voltage contours are far from perfect circles.) also the circles are closer near the electrode and wider spaced further out, if you want each contour to be the same no of volts from each neighbour.


    Fence off a couple of rod lengths around the electrode for best results. Also for pets or small children, worth insulating the top foot or so, so that even if they get on the soil at the surface right near the centre there is at least some resistance in series

Reply
  • 0

    Sparkingchip:

    ...

    The diagram in this article suggests there can be the full voltage gradient 230 volts to zero across a cow on soil.

     




    The figure is rather simplified but is about right for a rod of say 1m to 1.5m length - half the voltage drop is in a circle of radius more or less equal to the rod length (all sorts of assumptions about uniform soil density and no wet or dry  patches or buried rocks are hidden- in reality the voltage contours are far from perfect circles.) also the circles are closer near the electrode and wider spaced further out, if you want each contour to be the same no of volts from each neighbour.


    Fence off a couple of rod lengths around the electrode for best results. Also for pets or small children, worth insulating the top foot or so, so that even if they get on the soil at the surface right near the centre there is at least some resistance in series

Children
No Data

Community Rules & Guidelines