Recent content by mikgle

  1. M

    Nuisance tripping - Earth Leakage Device on a TT system

    As newly qualified, my knowledge is obviously near the start of the learning curve, hence this forum. I would like to work alonside more experienced sparks but unfortunately noone is taking youngsters on around here at the moment. Unfortunately other replies seem to think that once qualified...
  2. M

    Nuisance tripping - Earth Leakage Device on a TT system

    I see, well the skts circuits are protected by the 30mA rcd, not sure about the lights - will have to check the other ccts when I do the Periodical but does it then become mandatory that I have to upgrade the protection on existing circuits, or can I just advise? Remember, what I am...
  3. M

    Nuisance tripping - Earth Leakage Device on a TT system

    Very clear. However, I'm not old/experienced enough to know whether the old type RCD's were called previously ELCB's or whether an old device labelled "ELCB" as in this case, is in fact a voltage-controlled device - this is what was confusing me as to what the device actually is. As I say, I...
  4. M

    Nuisance tripping - Earth Leakage Device on a TT system

    Does that make sense? Have you yet clarified what the device between DNO' cutout and meter actually is - an RCD or a voltage-operated ELCB? Kind Regards, John. Yes I understand what you're getting at John..... And no, I need to do a return visit and Unfortunately clients are away...
  5. M

    Nuisance tripping - Earth Leakage Device on a TT system

    When it was written back in 2005 the 16th edn regs were the current version which permitted this setup.
  6. M

    Nuisance tripping - Earth Leakage Device on a TT system

    [Don't you think it would be a good idea to conduct a PIR on the circuits first? You say you are qualified, just, does this mean qualified to complete your own building control notice through a competent persons scheme or are dealing direct with the LA building control. Yes, will be doing a...
  7. M

    Nuisance tripping - Earth Leakage Device on a TT system

    No, I meant "newly", hence my request for advice..... Getting back to the subject under discussion, why does a 100mA device not give discrimination over a 30mA one? And why would a 100mA device trip 9 times out of 10 before the 30mA one? Does'nt seem logical, unless there is a problem with the...
  8. M

    Nuisance tripping - Earth Leakage Device on a TT system

    All very valid comments, duly taken onboard... I can't remember about whether it had an earth lead going to the device, I only had time for a quick look as guests unexpectedly arrived! Definitely labelled "Earth Leakage Circuit breaker". also didnt know until later about these voltage devices...
  9. M

    Nuisance tripping - Earth Leakage Device on a TT system

    Zs = Ze + (R1 + R2) its the Ze part that suffers from a poor earth (electrode)?
  10. M

    Nuisance tripping - Earth Leakage Device on a TT system

    I think its to ensure one achieves a satisfactory Ze - it may be ok in wet weather but not in dry apparently.......
  11. M

    Nuisance tripping - Earth Leakage Device on a TT system

    Thanks John, a lot to take in here... I must admit i did consider a time-delay rcd but these are at least £60 more than the standard, not a great deal if its necessary but I rather was thinking (or maybe hoping?) that the main problem is the old type of voltage -controlled rcd that is currently...
  12. M

    Nuisance tripping - Earth Leakage Device on a TT system

    Will try - I'll be there when they come to fit the isolator, maybe I'll learn something from them?.... cheers
  13. M

    Nuisance tripping - Earth Leakage Device on a TT system

    don't know - they're the experts?
  14. M

    Nuisance tripping - Earth Leakage Device on a TT system

    yes, its a split load at the CU - skt circuits only are protected by a 30mA rcd. Presumably a 100mA overall RCD would provide discrimination....regards and thnkx
  15. M

    Nuisance tripping - Earth Leakage Device on a TT system

    Hi all you wise, experienced sparkies out there..... I'm only just qualified and my first job is to diagnose nuisance (usually happens in thunderstorms) tripping of the supply "Earth Leakage trip device" (100mA). I initially assumed this was an RCD but apparently I have since learned it could be...
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