Beware a little long.
I served an electrical apprenticeship a long time ago, then went back to full time education immediately moving away from mainly domestic electricity work to jobs with greater reward (and interest), and not crawling around filthy lofts. There have been significant advances in domestic electrics since I was crawling around lofts as a kid, notably, LED lighting, RCDs, RCBOs, AFDDs, SPDs and screwless connectors (which have made their way onto light fittings and some 13A sockets). I recall ELCBs for specialist applications when I was a kid, few had them in homes. The only real safety advance at the time. The words 'consumer unit' were unheard of.
I have always been an admirer of the German, French, Continental main panels. They are multi row, inset into walls, have an RCD on each row with the data/comms all in one neat attractive metal enclosure. Impressive and state of the art. We would have fuse boxes under stairs where you had to lay on your stomach to get at them. Or a fuse box high up on a wall in a downstairs toilet in new builds, having to stand on the toilet to reset a breaker. Appalling. We were/are third world to their latest equipment and ways. Their breakers are also double pole all through, to our standard single pole, and their twin L & N busbars reducing wiring in the main panels. All very well thought out and neat. I noticed last week Screwfix sell the Schneider multi row metal consumer unit and the twin busbars. So some hope there we are going their way.
However, when looking at the Continental main panels (I prefer those words) below the attractive looks, I was always struck at the many circuits just a two bedroomed apartment had, as they had dedicated radials to certain appliances and socket radials and breakers to a room or two rooms at the most. In Britain it was common to see three circuits in flats in a small 'fusebox': the socket ring circuit, cooker and lights. A relative has a 35 year old house, detached, 4 bed, two bathroom with an attached garage. Heat and hot water by gas. His consumer unit was high in the garage, needing a ladder to get to, but with only a five circuits: one ring, two lights, cooker and immersion. The immersion has never been switched on as it is backup only. I immediately though cowboy cheapo builders skimping, but he said he has been there 25 years and not once has he had problems of any sort. He even has a big American fridge, washing machine, dryer and dishwasher of the one ring. And of course the TV, laptop etc. He had his consumer unit changed to a Fuse Box model with all DP RCBOs fitted at face height.
It hit me that the ring circuit was why he did not need a mass of circuits to our radial fitting Continental cousins. I have always admired the genius, simplicity and economy of the ring circuit, which the British G type fuse in plug, protecting the flex, makes possible. I would argue with Americans and Continentals defending the ring, that there was two ways back to the main panel for the earth, the cables less stressed by current, and that as we were taught it was a socket busbar run around the house. It was also economical to install. You can plug in a 3kW appliance into any socket with it fully working. We all were on the side of rings, all of us, sneering radials used for sockets circuits. I have noticed Youtube channels like Efixx and a few others, promote radials these days, which many just follow without thinking. I suspect this is under the prompting of sponsor manufacturers who want to sell MCBs, RCBOs, more cable, etc.
The big criticism from Americans and Continentals of the ring was that if the ring is severed for some reason, loose connection or just cut, one of the cables on one of the ring's 2.5mm legs could overheat drawing too much current causing a fire, as it is protected by a 32A breaker. A fair point. But I pointed out 4mm cable can be used, so no problem. They pointed out that using two 4mm conductors in one socket terminal to make the ring is cumbersome, and may put stress on the cable as the socket in pushed in. A fair point, although this applies to radial and ring circuits. They said 4mm is rarely used for sockets as they have a limit to sockets on any radial. These days safety device introduction has made the ring far, far, safer, so should be the first circuit of choice.
Well where is all this leading to you may ask. For a number of years I was considering a total flat renovation of my 2 bed flat, new bathroom, kitchen, electrics, floors, all new pipes, new combi, new doors, skirtings, etc. Then I am set for life. I was on a budget, so had to look at where savings could be made. I looked at the electrics. Skimming the forums here I gleened over the years since I was inactive in electrics, that the regs had changed markedly, and new safety devices introduced. The forum helped me here. I was aware of screwless connectors from commercial Continental applications I had seen, being impressed, but the new small Wago and In-Sure were new to me. The forum made me aware of double pole RCBO and AFDDs, and the regs relating to AFDDs and SPDs and that induction hobs were available on 13A plugs.
The forum directed me to the reg that I needed an 'expensive' AFDD on any circuit with a socket on it as the block I live in has too many floors to be exempted. So, with safety in mind and the reservations of Americans and Continentals on the ring circuit in my mind I designed the electrical installation for the flat. I ended up with 'three' circuits:
1. The hob and oven circuit. The hob can be on a 13 amp plug and oven draws about 14 amps. They both are off one 4mm T&E cable on a 32A DP RCBO. Both on a 20A isolator switches in an adjacent cupboard.
2. The ring circuit. It supplies all the sockets in the flat, as it is less than 100 square metres and one fused spur to the combi. It is in 4mm T&E cable on a DP 32A AFDD (32A is max these days for rings I read). A number of forum members mentioned having screwless lever connectors in backboxes taking the ring's load, then 2.5mm flex to the sockets. All using Wago or In-Sure lever connectors. I went this way using ferrules on the flex. Then no problems of having to use the socket terminals with two cumbersome 4mm conductors in them. The 4mm cable was easy to fit into the backboxes using the screwless lever connectors. Then the socket terminals do not take the ring's current load. This raises safety levels, just what I want. If the ring is severed the 4mm cable will not overheat, as the 32A AFDD will protect it, just what I want.
Washer/dryer and 3/4 dishwasher have sockets in adjacent cupboards. Using diversity the ring will be under the 32 amp current draw.
3. Lights. All LEDs with a DP RCBO on 1.00mm T&E cable. One dimmer in living room serving three skirting height 5A round pin light fittings for table lamps.
Only drums of 4mm and 1.00mm cable making it cheap as per metre the cable is cheaper in larger drums. The 2.5mm flex was three-core 2.5mm flex with the outer sheath removed. Quite cheap, cheaper than buying three single cores. The consumer unit was a small cheaper metal job with an SPD. It does not take up space being very small and near to a large plastic enclosure, housing the Modem, data distribution to all rooms using RJ5 sockets, etc. Trunking used so no cables seen making it very neat. Had the installation signed off. Safety levels are 'very' high for minimum cost.
Money saved meant I could buy stainless flat plate sockets and light fittings and superior shower brassware. Yet high levels of safety.
Due to the simplicity and brilliance of the ring we do not need a multitude of radial circuits and big consumer units. So thanks to the many on the many threads over the past years I picked up all this current information on safety devices, low current hobs, and regs.
I served an electrical apprenticeship a long time ago, then went back to full time education immediately moving away from mainly domestic electricity work to jobs with greater reward (and interest), and not crawling around filthy lofts. There have been significant advances in domestic electrics since I was crawling around lofts as a kid, notably, LED lighting, RCDs, RCBOs, AFDDs, SPDs and screwless connectors (which have made their way onto light fittings and some 13A sockets). I recall ELCBs for specialist applications when I was a kid, few had them in homes. The only real safety advance at the time. The words 'consumer unit' were unheard of.
I have always been an admirer of the German, French, Continental main panels. They are multi row, inset into walls, have an RCD on each row with the data/comms all in one neat attractive metal enclosure. Impressive and state of the art. We would have fuse boxes under stairs where you had to lay on your stomach to get at them. Or a fuse box high up on a wall in a downstairs toilet in new builds, having to stand on the toilet to reset a breaker. Appalling. We were/are third world to their latest equipment and ways. Their breakers are also double pole all through, to our standard single pole, and their twin L & N busbars reducing wiring in the main panels. All very well thought out and neat. I noticed last week Screwfix sell the Schneider multi row metal consumer unit and the twin busbars. So some hope there we are going their way.
However, when looking at the Continental main panels (I prefer those words) below the attractive looks, I was always struck at the many circuits just a two bedroomed apartment had, as they had dedicated radials to certain appliances and socket radials and breakers to a room or two rooms at the most. In Britain it was common to see three circuits in flats in a small 'fusebox': the socket ring circuit, cooker and lights. A relative has a 35 year old house, detached, 4 bed, two bathroom with an attached garage. Heat and hot water by gas. His consumer unit was high in the garage, needing a ladder to get to, but with only a five circuits: one ring, two lights, cooker and immersion. The immersion has never been switched on as it is backup only. I immediately though cowboy cheapo builders skimping, but he said he has been there 25 years and not once has he had problems of any sort. He even has a big American fridge, washing machine, dryer and dishwasher of the one ring. And of course the TV, laptop etc. He had his consumer unit changed to a Fuse Box model with all DP RCBOs fitted at face height.
It hit me that the ring circuit was why he did not need a mass of circuits to our radial fitting Continental cousins. I have always admired the genius, simplicity and economy of the ring circuit, which the British G type fuse in plug, protecting the flex, makes possible. I would argue with Americans and Continentals defending the ring, that there was two ways back to the main panel for the earth, the cables less stressed by current, and that as we were taught it was a socket busbar run around the house. It was also economical to install. You can plug in a 3kW appliance into any socket with it fully working. We all were on the side of rings, all of us, sneering radials used for sockets circuits. I have noticed Youtube channels like Efixx and a few others, promote radials these days, which many just follow without thinking. I suspect this is under the prompting of sponsor manufacturers who want to sell MCBs, RCBOs, more cable, etc.
The big criticism from Americans and Continentals of the ring was that if the ring is severed for some reason, loose connection or just cut, one of the cables on one of the ring's 2.5mm legs could overheat drawing too much current causing a fire, as it is protected by a 32A breaker. A fair point. But I pointed out 4mm cable can be used, so no problem. They pointed out that using two 4mm conductors in one socket terminal to make the ring is cumbersome, and may put stress on the cable as the socket in pushed in. A fair point, although this applies to radial and ring circuits. They said 4mm is rarely used for sockets as they have a limit to sockets on any radial. These days safety device introduction has made the ring far, far, safer, so should be the first circuit of choice.
Well where is all this leading to you may ask. For a number of years I was considering a total flat renovation of my 2 bed flat, new bathroom, kitchen, electrics, floors, all new pipes, new combi, new doors, skirtings, etc. Then I am set for life. I was on a budget, so had to look at where savings could be made. I looked at the electrics. Skimming the forums here I gleened over the years since I was inactive in electrics, that the regs had changed markedly, and new safety devices introduced. The forum helped me here. I was aware of screwless connectors from commercial Continental applications I had seen, being impressed, but the new small Wago and In-Sure were new to me. The forum made me aware of double pole RCBO and AFDDs, and the regs relating to AFDDs and SPDs and that induction hobs were available on 13A plugs.
The forum directed me to the reg that I needed an 'expensive' AFDD on any circuit with a socket on it as the block I live in has too many floors to be exempted. So, with safety in mind and the reservations of Americans and Continentals on the ring circuit in my mind I designed the electrical installation for the flat. I ended up with 'three' circuits:
1. The hob and oven circuit. The hob can be on a 13 amp plug and oven draws about 14 amps. They both are off one 4mm T&E cable on a 32A DP RCBO. Both on a 20A isolator switches in an adjacent cupboard.
2. The ring circuit. It supplies all the sockets in the flat, as it is less than 100 square metres and one fused spur to the combi. It is in 4mm T&E cable on a DP 32A AFDD (32A is max these days for rings I read). A number of forum members mentioned having screwless lever connectors in backboxes taking the ring's load, then 2.5mm flex to the sockets. All using Wago or In-Sure lever connectors. I went this way using ferrules on the flex. Then no problems of having to use the socket terminals with two cumbersome 4mm conductors in them. The 4mm cable was easy to fit into the backboxes using the screwless lever connectors. Then the socket terminals do not take the ring's current load. This raises safety levels, just what I want. If the ring is severed the 4mm cable will not overheat, as the 32A AFDD will protect it, just what I want.
Washer/dryer and 3/4 dishwasher have sockets in adjacent cupboards. Using diversity the ring will be under the 32 amp current draw.
3. Lights. All LEDs with a DP RCBO on 1.00mm T&E cable. One dimmer in living room serving three skirting height 5A round pin light fittings for table lamps.
Only drums of 4mm and 1.00mm cable making it cheap as per metre the cable is cheaper in larger drums. The 2.5mm flex was three-core 2.5mm flex with the outer sheath removed. Quite cheap, cheaper than buying three single cores. The consumer unit was a small cheaper metal job with an SPD. It does not take up space being very small and near to a large plastic enclosure, housing the Modem, data distribution to all rooms using RJ5 sockets, etc. Trunking used so no cables seen making it very neat. Had the installation signed off. Safety levels are 'very' high for minimum cost.
Money saved meant I could buy stainless flat plate sockets and light fittings and superior shower brassware. Yet high levels of safety.
Due to the simplicity and brilliance of the ring we do not need a multitude of radial circuits and big consumer units. So thanks to the many on the many threads over the past years I picked up all this current information on safety devices, low current hobs, and regs.
Necessity (being broke) is the mother of invention. 
