I wonder, if we vote, for or against AFDD, what kind of result might we get?

ebee said:

I wonder, if we vote, for or against AFDD, what kind of result might we get?

Isn't that sort of what already happened with cross-industry representation in the BSI committees responsible for BS 7671, who came to the consensus of what we have?

I don`t know Graham, some things seem to get a big thumbs down in to what I consider the popular vote but seem to make it in sometimes. Well it appears to me but I may well have a totally slanted view of such things and that is why I commented. I`ve seen more suggestions they have very limited safety effect, not much safety versus cost effectiveness but plenty of the "well I wouldn`t have them" sort of attitude. Mind you RCDs probably had a not very good press a few years ago but I am a fan of them.

It depends what you mean by cross-industry. The standards writing circuit is quite cliquey, and a quick look at the list shows it is dominated by larger outfits, presumably  as most small organizations, despite being the majority of the businesses, cannot afford to send someone along being too busy with the day job. I'm not convinced either that the likes of NICIEC actually know what all its 25 thousand odd members actually think/want, and as a result it also probably over represents those who are larger more vocal  perhaps benefiting those wanting bigger contacts and lots of new work, over those who have to maintain it later and in effect have to pay for the design decision.

I'm not sure how one would fix that, it is certainly not a uniquely '7671 thing, but I'd be wary of assuming it is truly a representative cross-section of informed opinions. (The DPC might be better but the commenting process is quite convoluted, not especially well publicized and the window for making comments is quite short.)

Mike

ebee said:

Well it appears to me but I may well have a totally slanted view of such things and that is why I commented.

I can completely understand that. I also understand the situation we've all found ourselves in, moaning that absolutely everything is sub-standard or doesn't work, because of the sheer number of problems we've had to fix.

More importantly, though, I also value the points of view put forward.

Not that I haven't (regularly) done it myself, but Engineers are a cynical bunch (at least about their own profession), and do moan about things "never being right". - there are, as I said, reasons for that. And I also understand that changes in BS 7671 provide yet another set of problems to fix one way or another.


But to make decisions on what ought, or ought not, to be included in a standard, and to what degree, requires a number of different perspectives on an issue to be taken into account ... and also a little thinking outside the box.

For example, with cable sizing, let-through energies etc., there's a huge difference in the perspective of someone working mainly on up-to-100 A domestic installations, vs different range of prospective fault currents, wider variety of circuit configurations, and larger premises, as well as larger loads, in some other installations. Hence, the contents on circuits in BS 7671 itself is far larger than the "here's your answer" (OK, "industry rules of thumb") in the tables in Section 7 of the OSG.

ebee said:

I`ve seen more suggestions they have very limited safety effect, not much safety versus cost effectiveness but plenty of the "well I wouldn`t have them" sort of attitude. Mind you RCDs probably had a not very good press a few years ago but I am a fan of them.

Again, I fully appreciate that, and the point about RCDs is exactly that (and only that) which I was making.

ebee said:

Well it appears to me but I may well have a totally slanted view of such things and that is why I commented.

I can completely understand that. I also understand the situation we've all found ourselves in, moaning that absolutely everything is sub-standard or doesn't work, because of the sheer number of problems we've had to fix.

More importantly, though, I also value the points of view put forward.

Not that I haven't (regularly) done it myself, but Engineers are a cynical bunch (at least about their own profession), and do moan about things "never being right". - there are, as I said, reasons for that. And I also understand that changes in BS 7671 provide yet another set of problems to fix one way or another.


But to make decisions on what ought, or ought not, to be included in a standard, and to what degree, requires a number of different perspectives on an issue to be taken into account ... and also a little thinking outside the box.

For example, with cable sizing, let-through energies etc., there's a huge difference in the perspective of someone working mainly on up-to-100 A domestic installations, vs different range of prospective fault currents, wider variety of circuit configurations, and larger premises, as well as larger loads, in some other installations. Hence, the contents on circuits in BS 7671 itself is far larger than the "here's your answer" (OK, "industry rules of thumb") in the tables in Section 7 of the OSG.

ebee said:

I`ve seen more suggestions they have very limited safety effect, not much safety versus cost effectiveness but plenty of the "well I wouldn`t have them" sort of attitude. Mind you RCDs probably had a not very good press a few years ago but I am a fan of them.

Again, I fully appreciate that, and the point about RCDs is exactly that (and only that) which I was making.