More Old Regs Stuff

[JohnW2]

Two single sockets spurred from a ring that used to be allowed...didn't it?

Yes, it did ... but I don't think it is true that it is "not allowed", even now, is it? As far as I am aware, the limit of "one single or double socket" exists only in the guidance of Appendix 15 of BS 7671, not as an actual 'regulation'.

Not sure why I wouldn't be allowed as it makes sense

Maybe it resulted from someone feeling that two single sockets represented a potentially laarger total load than one double (particular if they believed that a double socket was not 'rated' to supply 2 x 13A).

It may also have been because they felt that the very simple rule of "only one socket" could not be misinterpreted?

However, we can but speculate

 

[JohnW2]

I have also made similar comments on here as I'm totally convinced it was in the regs, I've certainly fitted a few 16A+RCD in an enclosure for external circuits off a ring

I don't think that, strictly speaking, it has never been allowed, since, as far as I am aware, the reg which allows ring finals (i.e. which allows a cable with a CCC as low as 20A to be protected by a 30/32A OPD) has never changed significantly since it first appeared, and hence has always limited ring finals to supplying "accessories to BS 1363) ... don't forget that, as I wrote earlier, that reg (which has remained essentially unchanged) appeared long before we had MCBs.

 

[securespark]

The 14th allowed two singles, or one twin or one piece of stationary equipment on an unfused spur.

But in my diagram earlier in this thread, it shows three singles.....

As far as I can tell, that reg changed when the 15th came in in 1981, but the 14th was allowed to be used until 1 January 1985.

 

[pete01]

But in my diagram earlier in this thread, it shows three singles.....

Just had a look I think it shows two singles taken from the original part of the ring single.

Interesting diagram though.

 

[Harry Bloomfield]

The 14th allowed two singles, or one twin or one piece of stationary equipment on an unfused spur.

But in my diagram earlier in this thread, it shows three singles.....

It shows a single socket actually on the ring, with a single spur socket added to that, then a second spur off the first spur. As I recall, that was allowed, but two was the limit back then.

 

[SUNRAY]

Been trawling online bookshops for old regs and guides again, sad old git that I am.

My latest is this:

View attachment 376216
It's the September 1976 Metric edition.


Ever wondered where the inspiration for Appx. 15 came from?
View attachment 376217

Four things immediately slap me in the face here:

1. You could use a 15A CB instead of an FCU.

2. Three sockets on a non fused spur. In my early copy of the 14th, you could have two single sockets or one double or one stationary appliance. Maybe the Metric 14th was changed? Can anyone with a Metric 14th tell me what A40 says?

3. Recommended fusing for plugs is at 3 or 13A, which is what is recommended now.

4. Mention of CCA cable. As late as 1976.


View attachment 376220


Changes to the definition of LV in April 1976
View attachment 376221

Could we see page 13 please as it seems to be showing BS196 connectors used on ring circuits

Another interesting point is this shows metric sized cables, I recall using imperial 3/0.029 singles for several years beyond 1966DOH 1976 revision

 

[securespark]

Could we see page 13 please

Yes, when I'm home!

 

[securespark]

Re the three sockets, thanks guys....

My eyesight is atrocious!

 

[securespark]

Could we see page 13 please as it seems to be showing BS196 connectors used on ring circuits

Another interesting point is this shows metric sized cables, I recall using imperial 3/0.029 singles for several years beyond 1966DOH 1976 revision

 

[securespark]

See A43 and A44.

 

[SUNRAY]

Thanks, from what I saw in you initial post I saw the BS196 but now I see they are for non-domestic situations.