I never install ring circuits, the potential for danger is unacceptable

[The Ghost]

The RFC is an artefact of materials shortage during WWII

Not true

 

[Squid]

Not true

It was, after the war and to keep costs don for the rebuilding program,

 

[The Ghost]

It was, after the war and to keep costs don for the rebuilding program

Not true.

 

[Pete999]

I’d like to know if anyone else here refuses to install ring circuits in domestic premises.

For me it’s either a 20a radial / tree circuit with 2.5mm, or a 32 radial / tree circuit with 4.0mm.

Frankly I’m tired of finding broken ring circuits on 32a CB’s, as well as mismatches on end to end tests. It drives me nuts on jobs that should be simple.

I wish we would get rid of this ridiculous practice here in the UK.

I know some of you will say there’s nothing wrong with it when it’s properly installed and tested, but inevitably at some point in the future someone will come along and disconnect a conductor unknowingly while changing outlets on the circuit.

Testing is more complicated, and diagnosing faults on a ring also.

 

[Squid]

It was designed as a lower cost option and a more efficient installation, therefore to help keep costs down.

 

[StephenRowley]

Do what works best for you. There both accepted way according to the regs.

 

[static zap]

I Tee.....Common on diy and builder installs.

-Does that translate in to-
"Hidden junction box hell ?"

 

[Andy78]

Same old argument. "Ring circuits are dangerous if someone who has no clue messes with them." Same goes for any circuit.

I find precious few ring final faults and have never seen any substantial evidence that significant danger is posed even when rings have been made discontinuous. Only in theory.

Anything installed properly is safe. Anything installed then messed with has the potential for danger. The argument has no point.

 

[Lucien Nunes]

I think the OP uses 'tree' to describe an ad-hoc radial with branches but it has a much older, more established meaning. The tree system of wiring was used in the late 1800s and early 1900s as an alternative to the distribution system that we use now (i.e. terminating a main or submain in a DB and distributing circuits from there).

In the tree system, the main would take a shortish, straightish route through the building and wherever a circuit was needed, a local fuse would branch off. Like taps in a riser busbar, but not necessarily in a riser. The main could also taper like the trunk of a tree, as it could be fused down stepwise as branches relieved it of some of the load. Pattresses with one or two pairs of ceramic pepperpot fuses would be dotted around here there and everywhere, resulting in difficulty of isolation and localisation and inflexibility once installed.

The advantage of a tree, in some layouts, was that less wiring and shorter runs were often possible, giving lower drop for the same amount of copper. But the flexibility of the DB method had won out by the 1920s and tree wiring was soon abandoned.

 

[Barnaby Stedman]

anway 2.5mm is way easier to play with whether you are running/stripping/connecting than big 4mm or 6mm radials.
I thought houses were built square to facilitate ring circuits weren't they?

 

[Lucien Nunes]

When the topic was last aired, I said I would like to see examples of thermal damage to RFC cables caused specifically by overload of one leg, due to the other going O/C. None have been offered so far...

 

[Squid]

anway 2.5mm is way easier to play with whether you are running/stripping/connecting than big 4mm or 6mm radials.
I thought houses were built square to facilitate ring circuits weren't they?

When was electrikery invented and rolled out and I believe they had square built houses a long time before that........

 

[Intoelectrics]

Personally I've never come across a RFC that was broken and then overloaded. My opinion is that its not likely to happen in most homes, possibly the kitchen where there is a potential of higher wattage equipment being simultaneously used (which is one good reason to wire a kitchen on its own RFC). Again my personal opinion is that RFC's are less likely to be dangerous should a fault occur, an example, as a few have already mentioned - the continuity of the cpc is more likely to remain intact or at least partially intact for the majority of the circuit.

The only one problem I see with RFC's - The ignorant people who don't understand them.

Sorry O.P but you don't have my vote.

 

[static zap]

Easy fault finding = Making do without a mft , very DIY.
..because it works has not confirmed the "Earth" is any good..
-the proper phrase uses the word "protective"-!

 

[DPG]

I thought houses were built square to facilitate ring circuits weren't they?

I'm guessing there should be a smiley or two after this? Surely?

 

[telectrix]

the ring is dead.... long live the ring.

 

[Carl S]

A “tree circuit”, the Americans refer to them as a MWBC (Multi Wire Branch Circuit). Most electricians hate them, but they are a throwback to the past.

Another comparison is the UK Octopus wiring system, something I’ve installed myself for lighting but it can be used for power. It’s a good system so long as you have easy access to the central JB, fault finding is easy.

As for RFC’s, I’m in the fellowship of the ring (sorry Mr Tolkien).

 

[telectrix]

i wouls say that a "tre" circuit is one where there is a radial off the OCPD, which then branches into several branches, each feeding 1 or 2 outlets. ifthe junction is either MF or accessible, as long as it's installed properly and the feed from the OCPD is rated according to the total load, then it will comply. still not a good departure from a RFC. many a RFC insyakked 50 years AGO WITHOUT SOME NUMPTY MESSING WITH IT, IS STILL FIT FOR CONTINUED USE.

AND... thE bloody caps lock next to the "A", FAT FINGERS. ARRRRGHHH.

 

[Dave OCD]

Just to add another little angle, anyone done 4mm rings where insulation or circuit length is a bit of a concern ? I did it in a large kitchen a year or so ago. If anything [with 35mm boxes] I think the stranded 4mm is just as easy to terminate.

 

[orrell electrics]

I've heard it all now

Rings are dangerous lol

I always remember talking to a builder from Hungary who was slating the way we build houses in the UK

He really disliked building control.....

(Edited by staff, please respect forum rules, expletive removed).