- Joined
- 11 Jan 2004
- Messages
- 42,762
- Reaction score
- 2,641
- Country
Thats the problem, many are not properly installed or maintained, who is Slep?Keep rings ( properly installed and maintained ) and get rid of Slep and other incompetents like him.
A bit drastic, going into exile because he installs radials, its year since I installed a RFC, somehow the ROW manages without them ( with a few exceptions)To keep within volt drop rules with 2.5 mm² cable with a 25 amp MCB one is limited to around 25 meters, with same 2.5 mm² looking at 106 meters for a ring, so often you can't simply turn a ring final into two radials, and comply with volt drop.
7/0.029 is larger than 2.5 mm² so when the ring final was designed, with 30 amp fuse, even if the ring final was broken the overload was a lot less, and we should not have to plan for people fiddling and getting it wrong, the loop impedance tests every years should highlight any errors.
But to use radials means you really need 4 mm² cable so not a retro change. And I have found just as many 4 mm² radials where the person working on it clearly thought it was a ring and extended with 2.5 mm² as I have ring finals which have been broken, and broken ring is easy identified when testing, having a length of 2.5 mm² in the radial is harder to find.
But if we consider three 2.5 mm² radials can replace a ring final, then a home with three ring finals, then a 10 way consumer unit needs changing for a 16 way, with a cost of 6 extra RCBO's so the price is likely £70 more than with a ring final, which may be chicken feed with a re-wire, but on a new build home these pennies count.
Likely the kitchen is where ring final and radial will be most felt, if we follow the appendix and any appliance over 2 kW has dedicated feed great, but we don't, so a 32 amp ring with dish washer, tumble drier, and washing machine will hold in even with the odd boiling of a kettle. But that is not the case with 16 amp radials. So with radials you will need those dedicated feeds, so 6 RCBO's just for the kitchen.
I already have 16 RCBO's in this house, with his ideas with dedicated supply as appendix says, going to around 26 RCBO's not that I could do that as would also involve lifting floors, but if he wants radials he should leave the UK simple.
Yes, but an unrecognised break in a live conductor is more serious.I like rings because if there is one unregonised break in the earth wires, at least all the sockets will still have an earth.
Yes, but why not do that in the first place - with 25A?I like the idea that if a ring should get a damaged cable that can't be mended easily, the ring can be made into two separate 20 amp radial circuits.
Ok, but not really a valid reason - you are, in effect using 5mm².I like the idea of a ring being rated to 30/32 amps without having to use 4mm2 cable.
That depends on the routing of the cable.As much as I like the idea of a 30/32 amp radial in 4mm2, it means using more expensive cable.
It is much nicer.People have commented how pleasant it is to work with 4mm2 cable
W e l l , y e s , but...perhaps if 2.5mm2 was readily available as stranded T+E that would be better.
who is Slep?
That's not a reason for installing a ring in the first place.If a ring gets broken, it can be made into two 20 (or even 25) amp radials.
I asked that.The question was - why not do that in the first place.
The same as any other circuit.If one of these two radials got an unseen break in one of them, I can't convert them in the same way I could a ring. I'd have to run a new cable or make some damage.
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local