socket circuit

[paddyscouse]

hi can some one advise me what to use for a radial socket circuit, i was thinking about 4 mil with a 32a mcb for kitchen

would then 2.5 with a 20a mcb for other room and the same for upstairs x3 beds

 

[Guitarist]

Sorry Guitarist, that's not what i meant! What i meant to say was sometimes electricians do not know how to test a ring circuit! Humble apologies to someone i respect!

Only kidding TC. I figured that was what you meant, but couldn't resist quoting you on it. No apology needed :mellow:

 

[Guitarist]

Because each leg of a ring needs to carry 20a, and if covered in masses of insulation, 2.5mm won't be up to the job. Hence the need for a 4mm ring......don't get me wrong, a 4mm ring is a horrendous concept, but now and again has proved necessary!

A real pain in the backside if you find yourself in this situation. I always do everything possible to avoid it, including installing conduit where builders tell me "it's not necessary".... Like they know what the hell derating factors are. (apologies to any builder reading this who does know about cable factors)

Builder : Why are you putting the cable in that conduit stuff? My usual electrician just tacks it to the wall and we plaster over it.
Me: A) Because it keeps the plasterer from taking chunks out of it, and B) Because I can take the cable, inside its conduit, straight through your 24" of insulation. Next question...

 

[Guest55]

Most countries being, or past commonwealth countries, others accepting BS7671 as a recognised standard*. The later category covers a multitude of countries, which includes China, as many of our final circuits are Rings, as well as on my last project in China.

India, Pakistan, Cyprus, Hong kong, Singapore*, Malta, Gibraltar, Suadia Arabia*, UAE*, Bahrain*, etc etc!!

I've had time to consider this otherwise informative post and have a point to raise ;
Although these countries may use BS7671 as the basis for their own wiring regs , that doesnt necessarily mean they use ring mains as a standard wiring arrangement within domestic installations ??
They could still be using radials only as per the European norm.

 

[Guitarist]

I've had time to consider this otherwise informative post and have a point to raise ;
Although these countries may use BS7671 as the basis for their own wiring regs , that doesnt necessarily mean they use ring mains as a standard wiring arrangement within domestic installations ??

There's a good chance Eng has installed RFC's in those Countries mate

 

[Guest55]

There's a good chance Eng has installed RFC's in those Countries mate

This is what my rather good question hopes to reveal.

 

[malcolmsanford]

I can certainly speak for Saudi.

Domestically there will never be a RFC installed. I know of only one place where they are and that is a British Compound out here and was done by British engineers who designed it on basic domestic criteria .

Commercially yes I design all my IT socket circuits in RFC 4mm here if we don't utilize power track. If We utilize power track then we normally wire in 10mm singles from the CU to the track Termination box.

General power sockets will inevitably be in Radials as often you will get dual power through out an office ie American 127 and European 220. The 127 are normally the god awful American plugs, and though I personally don't like using MK 1363 sockets, if your utilizing the 2 phase to give you that 220volt, they are the ones asked for by the client and that is what we use.

More and more of the modern buildings are using 380/220 supplies, and even if it's the European voltage, Schuko sockets are rarely used, it will be mainly the UK BS 1363 with a smattering of Schuko

 

[Guest55]

^^^This confirms my understanding that domestic ring finals are rarely used outside of the UK , regardless of whether other countries borrow BS7671.

 

[Silly Sausage]

Hey TC

Google E45 it's soothing lol

sedgy, google E54...http://www.drugs.com/imprints/e54-10797.html

 

[Silly Sausage]

View attachment iee_ring_circuit_meeting.pdf

Found the above.

Point 1, page 1 seems to be the biggest advantage of an RFC.

 

[Guest55]

View attachment 13113

Found the above.

Point 1, page 1 seems to be the biggest advantage of an RFC.

Although several disadvantages for rings are listed in point 4 lol.

 

[Moses]

You may need to borrow Tony's thing there mate.
Now this is just my opinion and that of a few others, and that opinion will be contradicted by some but that 200 ohm figure in the regs is nonsense. With a little bit of thought and effort a Ze/Ra in the region of a TN system is easily achievable. All you need to do is remember depth is your friend with a TT, depth and the fattest rods you can buy.
Imho 200 ohms is not an acceptable reading upon which to base your earthing the best I've ever gotten on a TT was 0.29 and it didn't take that much work.

And you only got that, because you punched through the underground lead water mains!!!!! LOL

 

[trev]

And you only got that, because you punched through the underground lead water mains!!!!! LOL

Moses you said you would never tell anyone about that

 

[Engineer54]

This was the original question......

If rings are so great , why does no other country but the UK ''use'' them ?
Answers on a postcard please lol.

My reply/answer is correct, all the countries mentioned (as well as a good few more) have numerous projects where the British RFC has been utilised and in quantity!! As for Saudi Arabia, No-one asked or stipulated Domestic, although i know of at least one, high end residential rental project in Damman of around 450+ dwelling units ranging from 4 bed villa's to one bed apartments, that has used RFC throughout... I'm sure there are plenty more!!! Unless built by a decent sized developer/contractor, the general standard of domestic wiring in Saudi is at best atrocious and installed to no particular standard at all!!!

Malcolm,
My experience is slightly different to your own, on the 220/127V supplied buildings, where-by it's the BS 1363 accessories used on the 127V supply and either the Yank 220V outlet or the Schuko outlet on the 2 phase 220V supply (even seen the old British 15A outlets being used on there two phase 220V supply) As you know the outlet standardization thing, is a complete mish mash in Saudi, as well as in many other countries...

​

 

[malcolmsanford]

That's not a certain Aerospace company is it Col in Dammam....................wink wink

They are starting to worry more about standards over here, especially as they have now signed up to the G nations group. I'm asked al ot more in specs for this standard and that standard, and not very often now is it the NEC, but the BS 7671

But your right mate, property built 5+ years ago, unless it was prestige would be diabolical

 

[Engineer54]

That's not a certain Aerospace company is it Col in Dammam....................wink wink

They are starting to worry more about standards over here, especially as they have now signed up to the G nations group. I'm asked al ot more in specs for this standard and that standard, and not very often now is it the NEC, but the BS 7671

But your right mate, property built 5+ years ago, unless it was prestige would be diabolical

No, this was a totally private up-market rental complex, complete with restaurants, outdoor/indoor swimming pools, bowling alley, and even an ice skating ring among other bits and bob's!!

Just a shame the under spec'd concrete type and steelwork within is being eaten away by the sulphates and chlorides in the ground!! lol!!