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People Shocked in U.S. Swimming Pool.

Zoomup
Very dreadful.

https://www.youtube.com/watch?v=IusjgjINVn0


Z.
  • 0
    It  is very unusual for "ships" to connect to shore supplies, partly because loads can be quite large, and secondly because it ends up being very dangerous. Smaller boats are a bit different, and often plastic, so may be considered a bit safer. In the UK we insist on TT supplies which should be OK, but one still finds the odd narrow boat plugged into a random mains supply. We cannot win them all.
  • 0
    One ship I was regularly on, when in floating dry-dock in Hamburg and thus sitting on wooden blocks, shore power - 3-phase, 3-wire 440v 60 Hz used to be connected into a shore connection in the Focsle. Thence back fed through the 3.3 kV 3-wire connection to the main switchboard where it was available for 440v and 220v distribution. The only actual users of 3.3 kV being the bow-thruster motor - about 1MVA (not needed in dry-dock) and four refrigeration compressors. (All these were D.O.L. started when in normal use.).  Due to welding works, there was always a cable between the ship's hull and the steel work of the floating dock.

    I spent many happy time walking half bent over beneath the ship for such things as echo-sounders and speed-log.

     http://www.shipspotting.com/gallery/photo.php?lid=1529897


    Clive
  • 0

    mapj1:

    Generally people are less conductive than salt water ,and more conductive than fresh. 


    If you are the high resistance element, you do not want to be in series with a body of conducting water - swimming as it were in between the capacitor plates and  finding most of the volts dropped across you .




    I can certainly understand that grasping a (stainless) steel ladder in order to exit a pool could be risky. However, in this incident, where was the live electrode in contact with the water, and where was the "ground".

  • 0

    davezawadi:

    It  is very unusual for "ships" to connect to shore supplies, partly because loads can be quite large, and secondly because it ends up being very dangerous. Smaller boats are a bit different, and often plastic, so may be considered a bit safer. In the UK we insist on TT supplies which should be OK, but one still finds the odd narrow boat plugged into a random mains supply. We cannot win them all.




    IIRC a Type 22 frigate could put up to 3 MW ashore for disaster relief. I just took that as a given at the time - I never gave any thought to earthing arrangements.

  • 0

    Alasdair Anderson:

    The fatal current doesn't circulate in the middle of the swimming pool. You need to be at the edge, preferably grabbing on to a metal hand rail or similar.

    Interestingly the Americans have also managed to kill people swimming in rivers/marinas/lakes due to connecting their boats to a shore supply and getting circulating currents (https://www.boatus.com/seaworthy/magazine/2013/july/electric-shock-drowning-explained.asp), mainly children, and even avoiding the need to grab an earthed rail if the voltage gradient in the water is sufficient. It may also be enough in a swimming pool. Note that the lack of RCDs in the supply systems (a requirement in the UK for supplies to small vessels as far as I am aware) is a major reason for such faults being undetected until it is too late.

    Alasdair




    That is a very interesting link Alasdair.


    Z.

  • 0

     



    As I understand it Chris, the whole pool water was at an A.C. potential above earth due perhaps to a faulty leaky underwater light seal or badly earthed under water metal light fitting, or both.

    The steel pole was at earth (ground) potential, so when the "live" children touched the pole they received a  shock.


    Z.
     

  • 0
    I always thought the term "LIVE" to be an odd one because by touching it you might no longer be so.


    Let`s hope them kids are OK now
  • 0

    weirdbeard:




    Zoomup:

    Very dreadful.

    https://www.youtube.com/watch?v=IusjgjINVn0


    Z.




    Hi zoomup, not sure if you are aware, but as an aidey des memories you have previously posted about this 2014 incident back in 2014

    https://www2.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=59630


     




    Hello Weird,

                           You expect me to remember that far back? I can hardly remember what I ate for breakfast. There is a West End stage show that has been performed over 28,000 times. Yes the same show. But each time the audience comprised mostly new people who had not seen the show before.


    Z.

  • Former Community Member
    0 Former Community Member

    Zoomup:




    weirdbeard:




    Zoomup:

    Very dreadful.

    https://www.youtube.com/watch?v=IusjgjINVn0


    Z.




    Hi zoomup, not sure if you are aware, but as an aidey des memories you have previously posted about this 2014 incident back in 2014

    https://www2.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=59630


     




    Hello Weird,

                           You expect me to remember that far back? 

     


    No but i would expect that you could read the 2014 date on the video in your OP :(
  • 0



     


    No but i would expect that you could read the 2014 date on the video in your OP :(

     




    Weird, don't worry be happy

    https://www.youtube.com/watch?v=d-diB65scQU


    Z.

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