Rings 'n' radials.

[bigclive]

So why do we even use ring mains at all? Is it true that they were introduced to reduce the amount of copper used in wiring during war times?

A ring main is probably the single circuit most likely to be miswired either during installation or modifications, and even if a wire pops out somewhere it will generally keep going albeit with a potential for cable overloading.

On the other hand two 20A radial circuits could be used with LESS cable and the extra benefit of a few extra Amps available if two radials are used to replace a single ring. (A kitchen comes to mind.)

On the other hand, very few appliances draw excessive power these days. Most heaters are 2kW and a vacuum is likely to be the highest momentary current draw as it's switched on.

So why don't we just ditch ring-main circuits in all new installations and be done with it.

Or are they saving that for the "18th edition" so they can make us all sit patronising update courses again.

 

[Andy™]

the only thing that ringmains could be safer than radials for, is it takes generally takes 2 earth faults before an earth is lost (unless there is a fault between earth terminal and pin in socket). since it should be tested periodically, it should be noticed and rectified.

depending on the job, ive started using 20A radials rather than ringmains

 

[jl-heating]

we do the same now,

radial up,

radial down,

ring for kitchen.

 

[boltonsparky]

Do away with the rings go for the radials every time!

Going off on a tangent... andyc you are 100% correct about the inspection and rectification but in reality many installations (domestic) go for 30-40years without inspection and testing. My friends house is on an estate that is 17years old and I'd bet the life savings on only one or two out of the 50+ houses having had a periodic in that time (I'm thinking of leafleting!)

 

[Andy™]

Do away with the rings go for the radials every time!Going off on a tangent... andyc you are 100% correct about the inspection and rectification but in reality many installations (domestic) go for 30-40years without inspection and testing. My friends house is on an estate that is 17years old and I'd bet the life savings on only one or two out of the 50+ houses having had a periodic in that time (I'm thinking of leafleting!)

unfortunately, most inspections only happen once something has failed. or in the case of a recent thread, someone has been killed

 

[boltonsparky]

unfortunately, most inspections only happen once something has failed. or in the case of a recent thread, someone has been killed

As with many things it has to kill someone before anythings done about it.

I wish people would realise that just because they're getting electricity and it's worked ok for the last 10 years doesn't mean it's safe!!!

Preventions better than cu... death!

 

[sparky999]

Yh starting a new build next week im choosing a radial to wire the sockets spoke to my collegue and he agrees we should start to use them.

 

[bigclive]

So at what point is the IET (why did they change from IEE?) going to realise that in general radials are a more sensible option?

I noticed that in Oz they use radials on their 240V system.

 

[Andy™]

since they are so widely used, i dont think they will be in a rush to ban them, but more advise to use radials instead

 

[Evans Electric]

The trade has been obsessed with ring mains for the last 40 years. There are sparks who lose control of their bowells if they come across a radial. I was asked to 2nd fix a terraced house by a builder once,(fell out with original sparks) He had wired three ring mains ,(1) Kitchen (fair enough) (2) three bedrooms , (3) lounge /dining.

 

[bigclive]

Maybe the exciting loop arrangement is the only excitement in their life alongside the two-way switching. :^O

I reckon they should phase ring mains out and enforce the use of radials with two feeding the kitchen. One extra breaker, one short length of twin and earth saved and 8 more Amps.

 

[Robojin]

As I understood it the last remaining reason for Ring was the 106m limit compared to 40m on a 20A radial

Yes, volt drop, and all other considerations noted

Just thought I'd throw another element to topic for discussion

 

[The Godfather]

As I understood it the last remaining reason for Ring was the 106m limit compared to 40m on a 20A radialYes, volt drop, and all other considerations noted

Just thought I'd throw another element to topic for discussion

But 4mm T&E does increase options.

The Boys

 

[Zeespark]

Don

Having 4/1.5 also limits options in terms of Zs, whereas if the cable was 4/2.5 then I would use it on most power circuits.

AndyGuiness Drink

 

[spinlondon]

Here's a link to an article on the Iet's website:

http://www.theiet.org/publishing/wiring-regulations/mag/2006/18-plugorigin.cfm?type=pdf

Might help explain things?