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RCBO

Discussion in 'Electrics UK' started by Albert, 31 Mar 2004.

  1. Albert

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    when an RCBO trips, is there a simple way to find whether it was a current leakage or overload, or we have to run a comprehensive test?
    Albert
     
  2. Big_Spark

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    You need to get your test kit out Albert.
     
  3. Albert

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    Oh damn it is too heavy...all the dust ;)
    Thanks
     
  4. ban-all-sheds

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    Not having RCBOs, I'd never thought about this. It would be a useful feature if the devices could have telltales to indicate why they tripped.
     
  5. Albert

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    This days it is called 'whistleblower'... :LOL:
     
  6. Big_Spark

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    It would be good for those that know what their looking at, but for most everyday people it would go over their head....

    The problem would be is you could only differentiate between overloads and faults in general, as any fault, except overload, will trip the RCD part of the RCBO (If you see what I mean), so you will actually be not a lot better off! :cry:

    Shame as it would be helpful in commercial and industrial settings.
     
  7. plugwash

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    the old mk 2 module rcbos did this (not that they are avilible anymore) and i'm sure i've seen other makes of 2 module rcbo with the leaver split into 2 parts to indicate how it should trip
     
  8. plugwash

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    i mean how it has tripped
     
  9. ban-all-sheds

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    Plugwash - this isn't like the Other Place - here we have decent forum software to use, and if you make a mistake in your post, or just decide to go back and rewrite history, you can click on the "edit" button and make the changes. There is no need to do a second post correcting the first.
     
  10. Big_Spark

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    Plug, they did this as the bits of kit doing the work were seperate, in an RCBO they have been combined.

    But even in the old ones, the RCD tripping simply let you know it was not an overload.
     
  11. Albert

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    I had a thought, (happens even to me..), that if we use a clampmeter to measure the current when the RCBO is on, it might give us an idea whether it is a current leakage or overcurrent according to the current level that was measured. Please don't shut me it is just an idea...could it work?
     
  12. BR

    BR

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    perhaps, if you had a meter with 'inrush' capability. but i fail to see the purpose. A megger or even continuity test will show up a 'current leakage'
     
  13. Albert

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    I don't know wether you read the messages above, the original question was about a simple way of identify the cause for a RCBO to trip, it could be overload current and/or current leake, without the need to disconnect and check the wires. the idea of using a clampmeter, is to put it around the wire coming to/from the RCBO and turn the RCBO on, a high current will indicate overload a low current will indicate current leakage. can this work if not could you explain why
     
  14. Big_Spark

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    Albert, in theory you could do what your suggesting, in fact a small digital meter could be built into the RCD measuring the current on the CPC, if this rises the trigger level of the RCBO, then the dispay freezes at that level until reset.

    If this display was on Zero, or below the trigger limit, then you know it is not an Earth fault.

    I am not sure of the cost of incorportating this technology into an RCD/RCBO, it might make them too expensive and too cumbersome for one module in a board.
     

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