why not make all circuits radial?

[telectrix]

that's why you fit the cpc as a ring in a radial computer circuit.

 

[sparks will fly]

Personal preference I suppose. Rather run 2x 2.5's than a 4mm and separate cpc. Especially if it's in T+E & visible.

 

[Steve_P]

Sort of depends on the structure of the building too. There's a lot of OLD (5-600 year old) buildings here and messing with 3 to 4 feet of cob wall to complete a ring for a circuit that will probably only have 4 sockets on really isn't worth any thought process, especially when the customer wants invisiwiring, even on the lighting hanging off exposed beams. There's also a lot of buildings on steep hills where the main part of the house is upstairs and maybe a couple of rooms and a bathroom below. Again, these cry out for a radial but generally 2.5mm on a 20A MCB, there's no point putting much more than that for a bedroom and store cupboard or two.

Just some thoughts for the radial Vs ring argument.

 

[migspat30]

when is the 18th coming out ?

 

[Victor]

Depends on what you have plugged in obviously.
But if you have dish washer, tumble dryer, washing machine, oven, etc etc etc plugged in then it soon adds up.
Granted the chances of someone running everything at once is slim but people do.

Here in France it is all radials, ring mains are not allowed. Each radial can have a max of 8 sockets and items such as washing machines, dishwashers and tumble dryers all have their own circuits

Attached photo is a consumer unit for a one bed cottage.

 

[delano]

Hi Victor, thanks for the picture and info. It seems a bit extreme to put each appliance on its own circuit. However, after the initial surprise at that system and fuse board I believe it's a better way ultimately. I've noticed in Italy, their or some of their CCU's use double pole circuit breakers, so, no neutral bar.

 

[Victor]

It is all duel pole here.

What is a bit ott is that if a property is over 75sqm then you have to have 3 RCD's, 2 of which must be type AC and 1 type A. If over 100sqm then 3 type AC and 1 type A so 4 in all

 

[Engineer54]

Here in France it is all radials, ring mains are not allowed. Each radial can have a max of 8 sockets and items such as washing machines, dishwashers and tumble dryers all have their own circuits

Attached photo is a consumer unit for a one bed cottage.

View attachment 20708

And what would be the supply authorities cut-out fuse rating for that one bed cottage??

I think you're photo is a perfect example of what happens to the size of a UK CU when you start using radials for everything rather than applying the correct circuit design for the job in hand!!
I bet you can't use 32A 4mm radials in France, for a radial socket outlet circuit?? From what i can remember, socket outlet connection terminals are made to accommodate a max of 2 X 2.5mm. so no so called spurs off the outlet terminals either!!

 

[Victor]

16amp 2.5mm radials, with a max of 8 sockets.

EDF cut out fuse depends on what you require, as the higher the amperage the higher your standing charge. To give you and idea, on a new build the total power EDF will give you on a monophase supply will be 12kw and for that the standing charge will be approx Euros 300 per year.

4mm cable is not used here, it tends to go from 2.5mm to 6mm with nothing in between.

 

[earache]

My only wish is that we go back to stranded T&E instead of this crappy solid core!

Standard stranded?

 

[Geordie Spark]

Confused..............all I said was touche?

You just keep yer hands off Wor Lass's touche !!! :angry_smile:

 

[Engineer54]

Hi Victor, thanks for the picture and info. It seems a bit extreme to put each appliance on its own circuit. However, after the initial surprise at that system and fuse board I believe it's a better way ultimately. I've noticed in Italy, their or some of their CCU's use double pole circuit breakers, so, no neutral bar.

Of course there is a Neutral bar, but instead of having a standard busbar you have a twin busbar, Phase and neutral (insulated)!!

 

[Rampantchilli]

Spark I know has recently walked from a job for a kitchen company, the owner was a retired electrical engineer, and the kitchen company work on fixed prices , so he gets 25 for a new socket in the kitchen, which is crap, but it all adds up.
anyway, engineer tells kitchen company, he wants an individual circuit for each appliance, washer, dish washer, fridge, built in oven, microwave, and tumble dryer all run back to main CU. spark says no way am I installing 6 circuits to existing cu, including breakers for 150. Engineer says you do it for price or you don't come in, I think he was shouting good bye from his van before the customer finished talking