D
Deleted member 9648
"Fool!!!
So now your telling us not to even bother with ensuring ''Stability'' in a TT installation now are you??"
Read more: http://www.electriciansforums.net/i...8-0-12-ohms-suppliers-ze-2.html#ixzz22nGzDl8e
The above was a response from E54 to a post of mine in another thread,now I'm not going to take issue with being insulted by his lordship as thats his style rather than have a proper adult discussion.
BUT....perhaps we can all input on this and if I can be shown the error of my ways I promise I'll go away and never ever get involved in a TT Ra 'discussion' again.
I'll ask this question.....What constitutes 'stability'. If you have an Ra of 20 ohms and it gets to 25 is that unacceptable to you?.....30?...40?....what?
Why,when we know that a 100ma S type RCD will operate within the requirements at an Ra of 500 ohms...and a 30ma @1667 ohms....is the Bs recommended max of 200 ohms unacceptable and why am I a fool for accepting it?....Why does a 200 ohms rod need to be stable when we know a dramatic increase in resistance will still work?
It seems to me that if you cant accept high Ra values and 'twigs'...(and most on here dont) then you have to achieve a low enough and guaranteed stable Ra to operate an OCPD....otherwise what is the point of stability?
Hopefully some of the regular and respected members on here (including E 54) will not be too bored with this subject to explain why I am so wrong and they are so right,because I simply dont get it, and I've been an electrician for 30 years.....(referring to small scale TT installs only....ie single dwellings/outbuildings etc)
So now your telling us not to even bother with ensuring ''Stability'' in a TT installation now are you??"
Read more: http://www.electriciansforums.net/i...8-0-12-ohms-suppliers-ze-2.html#ixzz22nGzDl8e
The above was a response from E54 to a post of mine in another thread,now I'm not going to take issue with being insulted by his lordship as thats his style rather than have a proper adult discussion.
BUT....perhaps we can all input on this and if I can be shown the error of my ways I promise I'll go away and never ever get involved in a TT Ra 'discussion' again.
I'll ask this question.....What constitutes 'stability'. If you have an Ra of 20 ohms and it gets to 25 is that unacceptable to you?.....30?...40?....what?
Why,when we know that a 100ma S type RCD will operate within the requirements at an Ra of 500 ohms...and a 30ma @1667 ohms....is the Bs recommended max of 200 ohms unacceptable and why am I a fool for accepting it?....Why does a 200 ohms rod need to be stable when we know a dramatic increase in resistance will still work?
It seems to me that if you cant accept high Ra values and 'twigs'...(and most on here dont) then you have to achieve a low enough and guaranteed stable Ra to operate an OCPD....otherwise what is the point of stability?
Hopefully some of the regular and respected members on here (including E 54) will not be too bored with this subject to explain why I am so wrong and they are so right,because I simply dont get it, and I've been an electrician for 30 years.....(referring to small scale TT installs only....ie single dwellings/outbuildings etc)