Am I on ring or radial sockets (test results included)

[plugwash]

However people should consider whether a ring really is an appropriate design for the particular installation, and not just shove them in as if it's some kind of required thing that must be done because 80 years ago a committee formed to deal with the problems of construction and materials shortages following WW2 said it was.

IMO there are really two seperate questions

1. 20A or 32A circuits? If you move down from 32A to 20A then IMO you want *significantly* more circuits. a 32A circuit can support two full size loads plus smalls, a 20A circuit can only support one full size load plus smalls, so I wouldn't be comfortable using it for more than a single habitable room and would want multiple of them in the kitchen.

2. If 32A then ring or radial? A ring (or 20A radial) is normally wired in 2.5mm², a 32A radial needs at least 4mm² and may well need 6mm². So your cable is significantly more expensive per meter. If you have to use 6mm² you are also likely to run into issues with terminal capacity. Not having to go back to the DB mitigates this to an extent but at least on TLC right now a 100m reel of 4mm² costs more than double a 100m reel of 2.5mm².

So I would expect that in most domestic properties rings would be the most economical soloution to providing sockets.

In an office where large loads were unlikely, but earth leakage can be high 20A radials may well be more sensible.

 

[ebee]

Not having to go back to the DB mitigates this to an extent but at least on TLC right now a 100m reel of 4mm² costs more than double a 100m reel of 2.5mm².

Yes the 4.0 to 2.5 price comparison is one thing to take into account along with stocking of more sizes of rolls of cable, plus clips sizes etc.
Although it is not just the material costs alone but can be the labour costs of first fixing as well.
Factor in the method of obtaining materials for jobs as well can vary the particular business model too.
Therefore cost comparisons of materials and delivery/usage do play a part.
Ring finals and radials both have both advantages (and disadvantages) when compared with each other, there is no outright winner for every circumstance, it is often a horsey coursey kind of thing.
Size of consumer unit and number of circuits can even play its part.
My working life started in 1971 so the mindset of the time probably played a part too, those whose working life started in the last 10 or 20 years probably envisage different things just for that reason, similarly what "normal life" was like up to reaching 21 years (or 18 years or whatever) .
So there might be differing reasons why some of us have differing bias one way or the other.

 

[AndyPRK]

I think most big loads are 10A. Rare to be 13.

These Damm sparks fit 2.5mm radials. (Except kitchens I hope)

 

[Harry Bloomfield]

1. 20A or 32A circuits? If you move down from 32A to 20A then IMO you want *significantly* more circuits. a 32A circuit can support two full size loads plus smalls, a 20A circuit can only support one full size load plus smalls, so I wouldn't be comfortable using it for more than a single habitable room and would want multiple of them in the kitchen.

I have here - two rings, numerous spurs, and a top of my head guess -maybe six radial socket circuits, all of which are 2.5mm. One of the problems 4mm and even more so 6mm, is the inflexibility, and difficulty of installation, of the larger sizes of such cables.

 

[EFLImpudence]

4mm² T&E being stranded is more flexible than 2.5.

 

[Ragnar_AT]

I think most big loads are 10A. Rare to be 13.

These Damm sparks fit 2.5mm radials. (Except kitchens I hope)

Exactly, if that. The only big loads outside the kitchen are electric fires and hair dryers. Even in the kitchen only hobs and ovens are likely to exceed 10 A. Kettles sometimes do but are only on for a minute or so per brew.

I can say from experience (living in Austria for a very long time) that a flat with five people (two adults and three children) can live quite comfortably in a flat with a 25 A single-phase supply and four 13 A circuits, a dedicated one for the dishwasher and the washing machine each and the other two for all the lights and sockets. We even survived fine when we had no gas for two days one freezing November and had to rely on electric heaters.

I‘m convinced a typical UK home could work perfectly with two 20 A radials (upstairs sockets, downstairs sockets) and probably two 20 A radials for the kitchen. We‘ve got an unprecedented number of gadgets to plug in these days but none of them are particularly big loads, many of them below 50 W each.

 

[Harry Bloomfield]

I can say from experience (living in Austria for a very long time) that a flat with five people (two adults and three children) can live quite comfortably in a flat with a 25 A single-phase supply and four 13 A circuits, a dedicated one for the dishwasher and the washing machine each and the other two for all the lights and sockets. We even survived fine when we had no gas for two days one freezing November and had to rely on electric heaters.

I agree, that is perfectly possible....

My tourer caravan, like many, relies for power upon what is known as a single 16amp supply 'hook-up', when on site. That 16amps is shared between blown air heating, fridge freezer, water heater, lighting, TV, kettle and at times a toaster, and water pump. In the background, it runs a charger/PSU.

 

[Risteard]

Remember that Risteard thinks the only point of the forum is to provide a platform for his supercilious grandstanding.

No. A major purpose is to demonstrate that you are a knob.

 

[morqthana]

... he responds with ... abuse.

 

[crystal ball]

Join the club

 

[plugwash]

Exactly, if that. The only big loads outside the kitchen are electric fires and hair dryers.

Until the central heating fails and the portable heaters come out.

 

[Ragnar_AT]

Until the central heating fails and the portable heaters come out.

Same category as an electric fire I‘d say. All the portable electric heaters I‘ve seen are below 10 A, so you could run two of them on a 20 A radial. In reality you
might even be able to run three, both because many electric heaters are on thermostats and won‘t be on all the time and because a B20 can take a considerable overload for a while (24 A indefinitely, 29 for up to an hour).

 

[AndyPRK]

and with a ring, you will be able to run at least 1 extra heater

 

[pete01]

I'd choose a 32 amp 4mm radial anyday...

When I do a commercial eicr and I see 15 rings my heart sinks

 

[Ragnar_AT]

and with a ring, you will be able to run at least 1 extra heater

Let‘s assume the typical UK home has one upstairs socket ring. That‘s three heaters on a B32/2.5 mm2. Splitting that very same ring into two 20 A radials gives you four heaters with slightly less cable. A 2 BR would work with just one 20 A radial.