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V.O.E.L.C.B.

Zoomup
It dawned on me fully today while working in an old holiday chalet circa 1940s.


The man in the next chalet was trying to use his old Black and Decker 1970s car boot sourced electric drill outside on the grass. He was making a wooden clothes hanger with wood and pegs. A jolly good job too.


I had had a quick look inside his chalet as he needs some new sockets. The  fuse box is an old cream coloured Wylex 6 way unit with fuse wire carriers. There is an old Crabtree V.O.E.L.C.B. installed before the fuse box.


As he worked in the garden drilling wood, it dawned on me that he had zero shock protection as he would if he had a R.C.C.B. installed.


It's strange how a picture speaks a thousand words.


Z.


  • 0
    I think you will find they have an inherent tripping current of 500mA
  • 0
    I think 500 mA is realistic as Normcall‍  says, assuming 30 mA would be very foolhardy.


    Time was a bit of an unknown, there isn’t any way to determine how long it took them to clunk off.


    Testing was just applying voltage  to the earthing system with a transformer to see what happened, with the anticipation of a clunk.
  • 0
    Zoomup:


    The man in the next chalet was trying to use his old Black and Decker 1970s car boot sourced electric drill outside on the grass. He was making a wooden clothes hanger with wood and pegs. A jolly good job too.




     




    A forty year old Black and Decker drill with a metal case, a Class I hand held appliance unlike the modern all insulated drills with plastic cases, being used outdoors?


    That probably comes under the heading of foolhardy as well.


     


  • 0
    Sparkingchip:
    Zoomup:

    The man in the next chalet was trying to use his old Black and Decker 1970s car boot sourced electric drill outside on the grass. He was making a wooden clothes hanger with wood and pegs. A jolly good job too.




    A forty year old Black and Decker drill with a metal case, a Class I hand held appliance unlike the modern all insulated drills with plastic cases, being used outdoors?


    That probably comes under the heading of foolhardy as well.




    Are you sure that it is Class I? I have a Wolf drill which was old when I bought it 40 years ago and it is Class II even though the gearbox forwards is metal.


  • 0
    If it much more than 50 years old that marks about half time in the development of the pistol trigger hand drill -
    history of electric drills, 1916 to date


    beware the adverts


    Time and the evolution of kit and manufacturing standards is a funny thing. Looking at that leaflet from 1940, 80 years ago, 1980 would be a mid point, and yet 1980 seems almost 'modern times' while as  I recall in 1980, stuff from  1940 felt like another much older era, but the interval is the same . Equally the youngsters tease me for stuff I recall as being 'so last century'.

    Mike.


  • 0
    I’m old enough to remember that the new fangled drills with the plastic bodies would never last as the metal bodied drills we had.


    It’s not just about the electrical safety of the drill itself, if you drill through a live cable it’s far better to do so with a drill that has a plastic body.
  • 0
    mapj1:

    Equally the youngsters tease me for stuff I recall as being 'so last century'.


    I still think of the last century as being the 19th Century. ?


  • 0
    it dawned on me that he had zero shock protection

    Why?


    If the drill is class I and correctly earthed and presuming the VoELCB is working, then ADS should occur as normal (and wuth less dependence on a good Zs too).


    If the drill is Class II (which I rather suspect) then he has shock protection by double or reinforced insulation, the ELCB makes no difference.


    It's lacking additional protection perhaps, but that's another matter.


      - Andy.
  • 0
    So, using such a device but connected between a 'PME neutral/earth' & "true earth" would give a mechanism that would disconnect if they moved more than about 50V apart.


    The VOELCB having the distinct advantage that it already has a set of high current contacts! 


    Maybe they arent so useless after all!

  • 0
    AJJewsbury:
    it dawned on me that he had zero shock protection

    Why?


    If the drill is class I and correctly earthed and presuming the VoELCB is working, then ADS should occur as normal (and wuth less dependence on a good Zs too).


    If the drill is Class II (which I rather suspect) then he has shock protection by double or reinforced insulation, the ELCB makes no difference.


    It's lacking additional protection perhaps, but that's another matter.


      - Andy.


    Too many assumptions Andy/ The drill, bought from a car boot sale for little money, had a plug that was not correctly wired.


    Z.


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