The Ring is dead, long live the Radial!⚡

[Pete999]

What is the reasoning behind RFCs not being permitted in kitchens?

Edit: you addresssed this above while I was typing.

Regulations numbers please, for your statements please, as far as I recall any fixed load of 2KW or over. a dedicated circuit is a recommendation only, unless it has been updated recently.

 

[LastManOnline]

Regulations numbers please, for your statements please, as far as I recall any fixed load of 2KW or over. a dedicated circuit is a recommendation only, unless it has been updated recently.

Not sure if you were addressing my point or not but the separate circuit requirements for a fixed load over 2KW can be found in Annex 55A, Final Circuit Arrangements (Normative), 4th Ed., page 306
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And what may that be, if I might enquire?
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So what tests do you do on a radial in those places that only do radials. Especially dead tests and live tests?

Vortigern. Are you out of bed and well rested. Good. Can we have a reasonable chat then! ?. I have mentioned elsewhere of the thread title been designed to provoke and so it has. I can appreciate the what the ring circuit means for you. After all it is as you say a clever design and the British track record in that area speaks for itself.
What I wanted to discuss with you are the assertions you made regarding the problems for radials. Assertions that instead of offering support for, you supplied speculation. The "tree and branches" scenario that you described as a nightmare to faultfind is found in which country? Where did that come from. Written on the side of a bus?
The scenario with the 4mm radial I have never seen in any country with radials (another UK).
And the Spanish CU with 31 ways?. People will wonderr if you have
travelled much.

Right now that I, ve gotten that offmyc
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And what may that be, if I might enquire?
[automerge]1598655015[/automerge]
So what tests do you do on a radial in those places that only do radials. Especially dead tests and live tests?

Vortigern. Are you out of bed and well rested. Good. Can we have a reasonable chat then! ?. I have mentioned elsewhere of the thread title been designed to provoke and so it has. I can appreciate the what the ring circuit means for you. After all it is as you say a clever design and the British track record in that area speaks for itself.
What I wanted to discuss with you are the assertions you made regarding the problems for radials. Assertions that instead of offering support for, you supplied speculation. The "tree and branches" scenario that you described as a nightmare to faultfind is found in which country? Where did that come from. Written on the side of a bus?
The scenario with the 4mm radial I have never seen in any country with radials (another U
And the Spanish CU with 31 ways?. (otherside of the bus?) People will wonderr if you havetravelled much.

Right now that I, ve gotten that off my chest can I ask you to consider this..(here's the rest of my post. I appear to have pressed a wrong button AGAIN)
What is the cost of the average ring circuit? For a rewire let me suggest a figure of 400 euro (pounds). So the homeowner has a ring circuit with a capacity of 32 amps. Let's remove a link from the ring between 2 corner sockets in the same room. Length 7 mts. Cost 3.50.Lets add 1.50 to it and buy a seco ond mcb.
Now give the homeowner a choice.

A ring circuit with a 32 amp capacity for 400 euro or 2 twenty amp radials for 402 euro. That's 8 extra amps capacity and an extra way for convenience.
What would be in their best interest?

I

 

[ipf]

Now as you correctly say, temp disconnect one end of your ring and you are back to your radial. End of. In fact the ring and the radial are first cousins, some might say brothers.
Put another way, a ring is simply 2 radials joined together at either end.

'Siamese radials', eh? Another name for a RFC?

 

[nicebutdim]

Obviously

My point throughout this thread has been that rings are often derided because of issues arising from modifications and that radials may well suffer from the same issues with the passing of time.

It would seem then we're in agreement that nothing is fundamentally wrong with either type of circuit and that each has its place dependant on circumstances.

 

[Maji236]

CLICK must be planning / looking at something that would make radials possible without having to use a 50 way D.B

My Son has just bought a 4 bedroom house in the U.S.A, it's got 3 D.B with a total of 58 circuits in them.
All sockets are on radials

In the US, the ring circuit is a totally different concept to me, everything is wired radial.

As I investigated this, it seems it's used to insure proper voltage & amperage depending on where the home is located in proximity to a power station.
Am, I correct?

Stateside, using a ring circuit, the issue would be to make sure it's connected back to the correct leg @ CU (panel)! If not, that'd be a dead short.

 

[davesparks]

In the US, the ring circuit is a totally different concept to me, everything is wired radial.

As I investigated this, it seems it's used to insure proper voltage & amperage depending on where the home is located in proximity to a power station.
Am, I correct?

Stateside, using a ring circuit, the issue would be to make sure it's connected back to the correct leg @ CU (panel)! If not, that'd be a dead short.

The ring final cir uit has nothing to do with proximity to power stations, what gives you this idea?

Incirrect connection can just as easily lead to a short circuit in the UK when connected to a three phase board.

 

[LastManOnline]

My point throughout this thread has been that rings are often derided because of issues arising from modifications and that radials may well suffer from the same issues with the passing of time.

It would seem then we're in agreement that nothing is fundamentally wrong with either type of circuit and that each has its place dependant on circumstances.

Agreed?. I regard that as a balanced summary

My point throughout this thread has been that rings are often derided because of issues arising from modifications and that radials may well suffer from the same issues with the passing of time.

It would seem then we're in agreement that nothing is fundamentally wrong with either type of circuit and that each has its place dependant on circumstances.

My point throughout this thread has been that rings are often derided because of issues arising from modifications and that radials may well suffer from the same issues with the passing of time.

It would seem then we're in agreement that nothing is fundamentally wrong with either type of circuit and that each has its place dependant on circumstances.

 

[Pretty Mouth]

A ring circuit with a 32 amp capacity for 400 euro or 2 twenty amp radials for 402 euro. That's 8 extra amps capacity and an extra way for convenience.
What would be in their best interest?

Diversity.

2 X 20A radials would have 8 extra amps overall compared to a ring covering the same area, but 12 amps less per circuit, if you see what I mean. Radials would work out more generous if the load is evenly distributed through the area covered. However, on occasions where the bulk of the load is concentrated in one area you might find one of those radials overloaded, while its sister sits idle. A ring on the other hand would have the extra capacity to deal with it.

 

[pc1966]

In the US, the ring circuit is a totally different concept to me, everything is wired radial.

You have to realise that the UK (and Republic of Ireland, and a few other countries) use fused plugs.

So we can have a large number of sockets off a 32A breaker, in fact our regulations don't limit the number, and then each appliance will have its own fuse, typically 3A, 5A or 13A, depending on what it needs.

Thus fault handling is usually the appliance fuse going, for example if the flex is damaged, but if the fixed wiring has a fault or someone manages to load enough sockets up then the breaker is there to clear it.

Because of this we typically will wire a whole floor of a house on one ring circuit with the two ends going back to the same breaker, and to make the cable cost lower we use 2.5mm cable (about 13 AWG, instead of 4mm, about 11 AWG, in most cases). This also has the advantage that our CPC (earth/ground wire) has no single point of failure, typically if the ring opens on the CPC the socket is still earthed by one leg, as are all others.

Now using 4mm you can run the same sort of thing (lots of 13A sockets on a 32A breaker) but you have a much shorter length before voltage drop becomes a limit, and an open CPC leaves the remaining sockets without ground/earth protection.

So it really is just for our general purpose socket outlets - for large fixed loads like cookers, showers, water heaters, etc, we put them on their own breaker as a radial circuit.

 

[Vortigern]

Hi @Edmond Noonan. So yes it is true I have not travelled much. I think the side of the bus thing is amusing. Regards the scenario you present my answer will be that I charge per socket and it would cost the same in each scenario. Also it would be on RCBO(s) so would cost around £30 per RCBO. I think the thing is when say wiring a house or even an office, as I do a lot of commerical, it is my understanding that we will not just install the circuits for the perceived/stated purpose but will also try to allow for other uses inevitably arising over time. So an office for instance may be full of computers with one company but the next company may be testing engineers and need more capacity from the sockets. With this in mind I would often prefer a ring circuit as it serves many types of needs.
As to the now fabled problems with radial fault finding I can accede that I may have it wrong, it is something I heard in fact from the guy who taught me that it is a nightmare, never thought to question it. I would add I do respect the guy who taught me he was very knowledgeable and a craftsman. As to 32 way CU I quoted that from something I had read more than once on the web. As I have stated originally radials and rings have their place. But...the Ring is King. Normally we use radials for fixed items of equipment high draw. Not usually as a socket circuit for general use. However I have often where appropriate installed radial circuits in singles and conduit, so they do have their place it's just second place to the ring.

 

[LastManOnline]

Diversity.

2 X 20A radials would have 8 extra amps overall compared to a ring covering the same area, but 12 amps less per circuit, if you see what I mean. Radials would work out more generous if the load is evenly distributed through the area covered. However, on occasions where the bulk of the load is concentrated in one area you might find one of those radials overloaded, while its sister sits idle. A ring on the other hand would have the extra capacity to deal with it.

That is an argument I accept. But I see it as one one based on possibilities rather than practicalities. You are looking at the radial circuit through UK eyes (which is entirely understandable) but speaking from an (ROI) point of view where heavy appliances are connected on their own circuits it is a non issue.
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Hi @Edmond Noonan. So yes it is true I have not travelled much. I think the side of the bus thing is amusing. Regards the scenario you present my answer will be that I charge per socket and it would cost the same in each scenario. Also it would be on RCBO(s) so would cost around £30 per RCBO. I think the thing is when say wiring a house or even an office, as I do a lot of commerical, it is my understanding that we will not just install the circuits for the perceived/stated purpose but will also try to allow for other uses inevitably arising over time. So an office for instance may be full of computers with one company but the next company may be testing engineers and need more capacity from the sockets. With this in mind I would often prefer a ring circuit as it serves many types of needs.
As to the now fabled problems with radial fault finding I can accede that I may have it wrong, it is something I heard in fact from the guy who taught me that it is a nightmare, never thought to question it. I would add I do respect the guy who taught me he was very knowledgeable and a craftsman. As to 32 way CU I quoted that from something I had read more than once on the web. As I have stated originally radials and rings have their place. But...the Ring is King. Normally we use radials for fixed items of equipment high draw. Not usually as a socket circuit for general use. However I have often where appropriate installed radial circuits in singles and conduit, so they do have their place it's just second place to the ring.

The "Ring is King" is a slogan that even I struggle to resist. My "not travelling much" comment was not meant to be offensive. I react to.your comments because you clearly have years of experience and hence exert greater influence Att the "End of the day" (a Roy Keane favourite) we are all products of our environment.

 

[Vortigern]

offensive

Edmond when you have bought up six daughters, nothing can offend you any more, none taken. Oh and as an afterthought you would be proud of me, I have just finished wiring a mosque and I did that in radial sockets exclusively not a ring final circuit in sight. The sad thing is I carefully calculated the load the client listed (very low) and thought radials would be good. I went in one day and an immersion heater had been installed by the plumber so I had to load another 3 kw onto the previously calculated load. I came in the next day and they had bought, not a 2kw oven but 3kw oven, and the gas hob I was told by the plumber could not be fitted as regulations said that no gas hobs are to be allowed any more, so they tried to get me to connect a 3.8 Kw hob as well. The radial was not looking good at this point the ceiling was in and plastered and painted, oh dear!

 

[LastManOnline]

Edmond when you have bought up six daughters, nothing can offend you any more, none taken.

Oh boy. I must acknowledge that this is one of those occasions where I am left entirely speechless (that does, nt happen very often).
That comment certainly puts ring and radial circuits into perspective.
Well done you. ?

 

[Vortigern]

I really meant brought of course, I didn't really buy them!!

 

[pc1966]

I really meant brought of course, I didn't really buy them!!

Here was me thinking you had a buy 5 and get 1 free offer!

 

[LastManOnline]

I really meant brought of course, I didn't really buy them!!

That's, left me even more speechless?

 

[davesparks]

So we can have a large number of sockets off a 32A breaker, in fact our regulations don't limit the number, and then each appliance will have its own fuse, typically 3A, 5A or 13A, depending on what it needs.

They also, as far as I know, don't specifically limit us to a 32A maximum for socket circuits.

 

[pc1966]

They also, as far as I know, don't specifically limit us to a 32A maximum for socket circuits.

That is true, the example given is 30A rewirable or 32A MCB, etc, but it is not explicitly stated that is has to be 32A.

Seeing 20A on a normal 2.5mm ring is fine. Odd and worthy of a note, but still fine.

But having a 20A ring in 1.5mm or a 45A ring in 4mm would very much be in the WTF? sort of territory and I think most would see it as a potential risk for future use/changes/misunderstandings even if it is not actually unsafe by itself.

 

[davesparks]

That is true, the example given is 30A rewirable or 32A MCB, etc, but it is not explicitly stated that is has to be 32A.

Seeing 20A on a normal 2.5mm ring is fine. Odd and worthy of a note, but still fine.

But having a 20A ring in 1.5mm or a 45A ring in 4mm would very much be in the WTF? sort of territory and I think most would see it as a potential risk for future use/changes/misunderstandings even if it is not actually unsafe by itself.

I wouldnt suggest a ring final circuit other than 32A, it would be too much hassle to design for no advantage.

I bet most of us have seen a 40A or 45A circuit feeding a BS1363 socket and not even batted an eyelid.

 

[ipf]

That is true, the example given is 30A rewirable or 32A MCB, etc, but it is not explicitly stated that is has to be 32A.

Seeing 20A on a normal 2.5mm ring is fine. Odd and worthy of a note, but still fine.

But having a 20A ring in 1.5mm or a 45A ring in 4mm would very much be in the WTF? sort of territory and I think most would see it as a potential risk for future use/changes/misunderstandings even if it is not actually unsafe by itself.

20amp on a normal 2.5 ring may have been done after an EICR.... to attain maximum Zs? Noted, of course, as said.
I've come across a ring in 1.5, not unknown, I suppose. Should it be ripped out and replaced or protected with a 20?
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I wouldnt suggest a ring final circuit other than 32A, it would be too much hassle to design for no advantage.

I bet most of us have seen a 40A or 45A circuit feeding a BS1363 socket and not even batted an eyelid.

Aye, what about a cooker unit with socket outlet?

 

[Maji236]

You have to realise that the UK (and Republic of Ireland, and a few other countries) use fused plugs.

So we can have a large number of sockets off a 32A breaker, in fact our regulations don't limit the number, and then each appliance will have its own fuse, typically 3A, 5A or 13A, depending on what it needs.

Thus fault handling is usually the appliance fuse going, for example if the flex is damaged, but if the fixed wiring has a fault or someone manages to load enough sockets up then the breaker is there to clear it.

Because of this we typically will wire a whole floor of a house on one ring circuit with the two ends going back to the same breaker, and to make the cable cost lower we use 2.5mm cable (about 13 AWG, instead of 4mm, about 11 AWG, in most cases). This also has the advantage that our CPC (earth/ground wire) has no single point of failure, typically if the ring opens on the CPC the socket is still earthed by one leg, as are all others.

Now using 4mm you can run the same sort of thing (lots of 13A sockets on a 32A breaker) but you have a much shorter length before voltage drop becomes a limit, and an open CPC leaves the remaining sockets without ground/earth protection.

So it really is just for our general purpose socket outlets - for large fixed loads like cookers, showers, water heaters, etc, we put them on their own breaker as a radial circuit.

Trying to understand the finer points of a UK consumer lashing & RCB install. The wife & I are hoping to stay in Scotland on an extended basis. It would stand to reason I should keep to my trade for work.
The mm to awg, & all the acronyms for parts are begining to sink in a bit. I also noticed your multimeters are a bit different 'looking' then I'm used to. Thanks for the clarifications. I didn't realise there is a fuse in each outlet, makes sense now. Also the individual switching is interesting too.
I really don't do alot of home wiring anymore. I do almost exclusively commercial & industrial at this point.
Cheers.

 

[DPG]

Trying to understand the finer points of a UK consumer lashing & RCB install. The wife & I are hoping to stay in Scotland on an extended basis. It would stand to reason I should keep to my trade for work.
The mm to awg, & all the acronyms for parts are begining to sink in a bit. I also noticed your multimeters are a bit different 'looking' then I'm used to. Thanks for the clarifications. I didn't realise there is a fuse in each outlet, makes sense now. Also the individual switching is interesting too.
I really don't do alot of home wiring anymore. I do almost exclusively commercial & industrial at this point.
Cheers.

The fuse is in the plug rather than the socket outlet.

 

[UNG]

Trying to understand the finer points of a UK consumer lashing & RCB install. The wife & I are hoping to stay in Scotland on an extended basis. It would stand to reason I should keep to my trade for work.
The mm to awg, & all the acronyms for parts are begining to sink in a bit. I also noticed your multimeters are a bit different 'looking' then I'm used to. Thanks for the clarifications. I didn't realise there is a fuse in each outlet, makes sense now. Also the individual switching is interesting too.
I really don't do alot of home wiring anymore. I do almost exclusively commercial & industrial at this point.
Cheers.

Are you mistaking multimeters for the Multi Function Testers (MFT's) we use for installation testing, we still use the standard multimeters but these are not capable of carrying out the tests needed to verify an installation

 

[Mike Johnson]

@Maji236

Just for you information, In France plugs are unfused, all sockets are on radials, maximum of twelve sockets in 2.5mm on 20A breaker or eight sockets in 1.5mm on 16A, kitchen supply must have at least six sockets above the worktop, water heaters and white goods have their own supply off the CU plus extract fans, power gates, roller shutters, the list goes on.
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I quite often see Fluke MFT's on e-bay being sold by someone in the USA?

 

[UNG]

Edmond when you have bought up six daughters, nothing can offend you any more, none taken. Oh and as an afterthought you would be proud of me, I have just finished wiring a mosque and I did that in radial sockets exclusively not a ring final circuit in sight. The sad thing is I carefully calculated the load the client listed (very low) and thought radials would be good. I went in one day and an immersion heater had been installed by the plumber so I had to load another 3 kw onto the previously calculated load. I came in the next day and they had bought, not a 2kw oven but 3kw oven, and the gas hob I was told by the plumber could not be fitted as regulations said that no gas hobs are to be allowed any more, so they tried to get me to connect a 3.8 Kw hob as well. The radial was not looking good at this point the ceiling was in and plastered and painted, oh dear!

Isn't it strange how despite asking the customer numerous times for details what is being installed you find that once the site is boarded and skimmed the installation requirements change.
Seems to be more common these days with the choice of hobs and ovens available that range from 2Kw to 10Kw add to that the fact that washing machines and dishwashers only cold fill now and heat the water they use and the customers perception that once you have a cable in position it is a never ending source of power whatever the load

 

[Andy78]

The Ring is dead, long live the Radial!
When wiring socket outlets do you:
1. Use ring final circuits
2. Use radial circuits

When cooking a breakfast do you:
1. Use bacon
2. Use sausages

 

[LastManOnline]

@Maji236

Just for you information, In France plugs are unfused, all sockets are on radials, maximum of twelve sockets in 2.5mm on 20A breaker or eight sockets in 1.5mm on 16A, kitchen supply must have at least six sockets above the worktop, water heaters and white goods have their own supply off the CU plus extract fans, power gates, roller shutters, the list goes on.
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I quite often see Fluke MFT's on e-bay being sold by someone in the USA?

That system sounds very much like what we have here with the exception of the socket circuit wired in 1.5mm and protected by a 16 amp breaker. Do our regs allow for it? Yes. But its marginal. It would have to be a clipped surface cable. Would you see it in practice? Never

 

[Mike Johnson]

No clipped surface cable either, all cable has to be double insulated and of the same c/c, therefore singles in flexible conduit or trunking.

 

[LastManOnline]

No clipped surface cable either, all cable has to be double insulated and of the same c/c, therefore singles in flexible conduit or trunking.

I, m a fan of the singles in flexible conduit. It's basically a, rewire able system. (when it's installed well). The continentals have a soft spot for the stuff.

 

[Mike Johnson]

I have never seen any sockets wired in 1.5mm in France, but I do have very limited access to other peoples installations, say about half a dozen since I retired.

 

[telectrix]

In the US, the ring circuit is a totally different concept to me, everything is wired radial.

As I investigated this, it seems it's used to insure proper voltage & amperage depending on where the home is located in proximity to a power station.
Am, I correct?

Stateside, using a ring circuit, the issue would be to make sure it's connected back to the correct leg @ CU (panel)! If not, that'd be a dead short.

the purpose of a ring is to share the load between both legs. e.g. cable rated at 27A (2.5mm in UK) with a ring circuit it almost doubles the current capacity. at the mid point a 30A load will share current 15A each leg. so cable is not overloaded. at other points on the ring, the sharing is proportional to the respective lengths of each leg. near 1 end, the short leg will carry more current than the longer leg, due to lower resistance.

 

[LastManOnline]

I have never seen any sockets wired in 1.5mm in France, but I do have very limited access to other peoples installations, say about half a dozen since I retired.

Have you sockets and switches in your bathroom?

 

[telectrix]

When cooking a breakfast do you:
1. Use bacon
2. Use sausages

both, also eggs, beans, tomatoes, mushrooms, hash browns, toat, and a pint of Old peculier.

 

[Andy78]

both, also eggs, beans, tomatoes, mushrooms, hash browns, toat, and a pint of Old peculier.

You forgot the black pud but I'll let you off ?

 

[telectrix]

You forgot the black pud but I'll let you off ?

but i don't like black pudding. diane abbott is labour. my political leanings are slightly to the right of maggie thatcher, (God bless).

 

[Mike Johnson]

Have you sockets and switches in your bathroom?

Yes, mine are RCBO protected.

 

[UNG]

You forgot the black pud but I'll let you off ?

In the interests of equality and diversity what about white pudding

 

[Pete999]

Not sure if you were addressing my point or not but the separate circuit requirements for a fixed load over 2KW can be found in Annex 55A, Final Circuit Arrangements (Normative), 4th Ed., page 306

Thanks

In the interests of equality and diversity what about white pudding

BPM Black Pudding Matters

 

[telectrix]

In the interests of equality and diversity what about white pudding

Dawn French or Vanessa Feltz.

 

[Pete999]

Thanks

BPM Black Pudding Matters

But they can't do Sums