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Shock Likelihood at Switch.

Mornin' All,


I have just inspected and tested a renovated  old flat's wiring. The original lighting wiring in places has no circuit protective conductor. The owner has installed metal plate light switches to two positions with wooden back boxes. At these two positions there is no circuit protective conductor. The flat has a new R.C.B.O. consumer unit and all other wiring is good.


I have recommended that the switches have a C.P.C. installed (difficult and disruptive) or be changed to all insulated types.


Just what is the shock risk at these two switch positions? What is the likelihood of the metal plates becoming live due to a fault? Has anyone every seen a metal plate switch break down so that the plates becomes live?


Thanks,


Z.

Parents
  • With the greatest respect to anyone doing EICs


    There are better electricians out there than you or I will ever be (There always are - better than I, at the very least at areas such as hospitals, mines, factories, HV, Commercial, Domestic, shops, ships, Automation, pumps and motors, Controls, etc)


    There are better, more learned people out there than you or I will ever be (I don't know everything and never will, even the best experts will argue with other experts about the minuite of details.)


    If you're registered with the NICEIC or similar, seek their input too, and just do as they recommend. Their advice is always with covering your back in mind.  It is always thought out and reasoned; it is not always the best advice for a specific circumstance, but the best advice that can be given over the phone.  I don't always agree with the NICEIC but in order to be "in the club" I sometimes just have to do what they say I have to do. 


    This forum brings in a whole range of people who have had much more experience than I in electrical areas that I have learned less of than others - EICRs are one example - I think I'm competent, and the NICEIC would agree from 13 years of assessments as an AC, but I don't do the dam things day in and day out - I actively dislike the dam things. Someone else who does these EICRs every day will always be better than I in deciding how to code a fault. 


    Some of those sorts of people have probably contributed to this thread with the best advice they can. (free of charge and with no Ulterior motives I believe)


    I know the ones that I hold in highest esteem and who's opinions I value the most. When a collection of valued opinions all say I'm wrong - with any code at all - Id give serious thought to considering if I am in fact, wrong. (Please forgive me if I am wrong here - I believe Zoomup probably posted this thread to get validation for his decision, but must have had some doubts about the decision in order to seek validation)


    I think the consensus in this case case would seem to be: Under the described circumstances, under no circumstances is an unearthed class 1 accessory OK for continued use or to be deemed satisfactory on an EICR. (Unless its an earth free installation or something very unusual like an isolating transformer has been fitted on the lighting circuit - even then - this is me trying to be overly clever and think outside the box - I'm not sure it would make a difference to the EICR coding - does anyone know if that would be a solution?)


    I know there are probably millions of unearthed class one accessories up and down the country, without even an RCD, its mostly never been a problem. Statistically - probably - an extremely small chance of there being an issue, made even smaller by the use of an RCD that would cut the fault duration to a very short time. I know the chances are, that he'll be fine for ever - I think everyone kind of knows that.


    But why take the risk if you don't need to? Against all of the professional advice, from every governing body and expert you're likely to come up against.............Code 2 and unsatisfactory is the only answer here I think........


    Kind Regards

    Tatty
Reply
  • With the greatest respect to anyone doing EICs


    There are better electricians out there than you or I will ever be (There always are - better than I, at the very least at areas such as hospitals, mines, factories, HV, Commercial, Domestic, shops, ships, Automation, pumps and motors, Controls, etc)


    There are better, more learned people out there than you or I will ever be (I don't know everything and never will, even the best experts will argue with other experts about the minuite of details.)


    If you're registered with the NICEIC or similar, seek their input too, and just do as they recommend. Their advice is always with covering your back in mind.  It is always thought out and reasoned; it is not always the best advice for a specific circumstance, but the best advice that can be given over the phone.  I don't always agree with the NICEIC but in order to be "in the club" I sometimes just have to do what they say I have to do. 


    This forum brings in a whole range of people who have had much more experience than I in electrical areas that I have learned less of than others - EICRs are one example - I think I'm competent, and the NICEIC would agree from 13 years of assessments as an AC, but I don't do the dam things day in and day out - I actively dislike the dam things. Someone else who does these EICRs every day will always be better than I in deciding how to code a fault. 


    Some of those sorts of people have probably contributed to this thread with the best advice they can. (free of charge and with no Ulterior motives I believe)


    I know the ones that I hold in highest esteem and who's opinions I value the most. When a collection of valued opinions all say I'm wrong - with any code at all - Id give serious thought to considering if I am in fact, wrong. (Please forgive me if I am wrong here - I believe Zoomup probably posted this thread to get validation for his decision, but must have had some doubts about the decision in order to seek validation)


    I think the consensus in this case case would seem to be: Under the described circumstances, under no circumstances is an unearthed class 1 accessory OK for continued use or to be deemed satisfactory on an EICR. (Unless its an earth free installation or something very unusual like an isolating transformer has been fitted on the lighting circuit - even then - this is me trying to be overly clever and think outside the box - I'm not sure it would make a difference to the EICR coding - does anyone know if that would be a solution?)


    I know there are probably millions of unearthed class one accessories up and down the country, without even an RCD, its mostly never been a problem. Statistically - probably - an extremely small chance of there being an issue, made even smaller by the use of an RCD that would cut the fault duration to a very short time. I know the chances are, that he'll be fine for ever - I think everyone kind of knows that.


    But why take the risk if you don't need to? Against all of the professional advice, from every governing body and expert you're likely to come up against.............Code 2 and unsatisfactory is the only answer here I think........


    Kind Regards

    Tatty
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