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Home Made R.C.D. tester.

Fred down the pub said that I can save money by not using a qualified sparks to test my R.C.Ds. He said that I can make my own R.C.D. tester. Is it safe? 

How to make RCCB tester at Home - YouTube


Z.
  • The test button on some designs of RCD does provide an audio-visual indication if the contact opening time is too long, by getting the test resistor so  hot so that it fails with a load bang. ..

    In such cases ,the test lamp maybe  preferable. 

    Beware of the resistance of filament lamps being highly non-linear - when cold they take about 10 times the hot current - i.e. the rated wattage.

    This is of particular significance to designers of lamp dimmers, where the current and voltage are not in the expected ratio for a  simple resistance.

    M.
  • Ah yes, 643.8, where a "30mA" RCD which happily lets 140mA run through you until you're dead, is deemed from testing to be satisfactory.
  • Zoom


    No BS EN 61557- 6 is the standard. We may have left he EU but are still members of CENELEC .
  • AJJewsbury:
    Haven't we left the EN bit of that now John?

    Nope, the UK (well just GB really) has only left the EU, we're still members of CENELEC.

       - Andy.


    I can still comply with that by not applying  test current for more than 2 seconds.


    Z.


  • wallywombat:

    Ah yes, 643.8, where a "30mA" RCD which happily lets 140mA run through you until you're dead, is deemed from testing to be satisfactory.


    Guidance note 3 used to suggest that an earth fault loop test be carried out before testing R.C.D.s. to prove effective earthing. It is easy to protect people and livestock during this test AND the testing of R.C.D.s as well, by warning people before hand, and keeping them away from exposed conductive parts and extraneous conductive parts.


    R.C.D.s do not limit the magnitude of current flow during a fault they just  disconnect it quickly. The note under Table 41.1 interests me. "Where compliance with this regulation is provided by an R.C.D., the disconnection times in accordance with table 41.1 relate to prospective residual fault currents significantly higher than the rated residual operating current of the R.C.D."


    And we must not forget Reg. 415.1.2. "The use of R.C.D.s is not recognised as a sole means of protection and does not obviate the need to apply one of the protective measures specified in Sections 411 to 414."


    Bearing in mind that R.C.D.s are not 100 per cent reliable,


    Can become faulty,


    And can sit untested for ten years or more.


    We should be wary.


    Z.



     


  • John Peckham:

    Zoom


    No BS EN 61557- 6 is the standard. We may have left he EU but are still members of CENELEC .


    CENELEC. A premier league team?


  • "CENELEC is the European Committee for Electrotechnical Standardization and is responsible for standardization in the electrotechnical engineering field. CENELEC prepares voluntary standards, which help facilitate trade between countries, create new markets, cut compliance costs and support the development of a Single European Market."


    What does "voluntary standards" mean here please?


    Z.
  • Non-enforcable, non mandatory. Cenelec has no police force working on it's behalf to find non compliant stuff.


    However other organisations, like agencies of governments, may still take the CENELEC document and make it's requirements into  law if they wish. Typically this leads to 'importers must ensure  that the  goods they import into the UK meet standards X,Y&Z, ( which is based on a CENELEC standards R,S & T )".

    Actually that is still not policed either but the idea is an attractive one to politicians.

    M.
  • I did an IET webinar on RCD testing which answers all the questions being asked here. You can still watch it on demand.
  • Top marks.

    I watched on demand because I was unable to see it live.