Spur from a spur - options

[ban-all-sheds]

...there was around 5 strands in the red and 5 strands in the blue rather than just the one (thicker) one in new cable.

Yes I know.

Why did you assume that red/black was a mistake and red/blue was what he meant?

 

[JohnW2]

...there was around 5 strands in the red and 5 strands in the blue rather than just the one (thicker) one in new cable.

Yes I know. Why did you assume that red/black was a mistake and red/blue was what he meant?

I didn't. In fact, quite the contrary, I asked him to confirm that red/black was what he meant. I wrote:

one would expect the cores to be black (not blue) and red. Is that the case?

Kind Regards, John

 

[ban-all-sheds]

As you say, theoretically 'not inconceivable' - but for a new build??

Why not?

What does "new build" mean? Does it necessarily mean a house in a new large scale development by a company like Barrats, or Wimpey?

Or might it be a pair of semis put up on a small plot of land acquired by a small local builder who used the same old codger of an electrician he'd been using for the past 40 years?

Obviously as time went by the chances of rubber persisting got smaller and smaller, but I don't know how quickly, or at what point one can start dismissing the possibility.

I thought it worth asking.



Of course, it might not be red and blue, it might be a very reddish brown, and blue. And it might be stranded not because it's old 7/.029, but because it's 4mm²

Interestingly, when doing a quick bit of searching to find when Imperial cable sizes were phased out, I found this:

http://yjcable.en.made-in-china.com...in-and-Earth-Cable-2-5mm-4mm-6mm-Strands.html

And it looks like the Aussies use this:

http://www.alibaba.com/product-gs/959501174/TPS_flat_twin_and_earth_cable.html

 

[JohnW2]

I didn't say an FCU was not needed on a ring, just that it isn't needed on a radial.

It might be.

Agreed, but would you fit one in a radial to which you were adding an extra couple of sockets?

As per what I've just written to you, no, one wouldn't normally do that if one had access to the 'main' radial, and could wire the couple of extra sockets from there in cable of adequate CSA. However, if all one had to 'work from' were a 'reduced CSA spur' from the radial, feeding one socket (which is what I had in my head, for no terribly good reason!), then one could not add a second socket without putting an FCU upstream of the first one, could one?

In passing, I think I've realised how my subconscious probably led me to some 'iffy assumptions'. When two ('full size') cables leave one point on a radial, I call them 'branches', not 'spurs'. I only use 'spur' in relation to a radial to refer to a reduced-CSA 'branch' - either supplying one socket or supplying multiple sockets via an FCU (just as with a ring final).

Kind Regards, John

 

[JohnW2]

I thought it worth asking.

It was - which is why I 're-asked', on your behalf, when we had received no reply.

Of course, it might not be red and blue, it might be a very reddish brown, and blue. And it might be stranded not because it's old 7/.029, but because it's 4mm²

Yep, all possibilities.

Kind Regards, John.

 

[ban-all-sheds]

Agreed, but would you fit one in a radial to which you were adding an extra couple of sockets?

Probably (but not definitely) not.