Why aren't ring circuits banned?

[chronyx]

Doing a lot of EICRs in London at the moment and I'd say every other C.U. has a ring circuit with no continuity on one of the conductors.

Seeing as the IET see fit to tinker around the edges constantly with the regs, I struggle to understand why these potentially extremely dangerous circuits are still permitted. Yet bonding and earth conductors have almost doubled in size because, well, they said so.

It's not 1949 anymore. Ban the damn things.

 

[chronyx]

I wouldn't know about that, but I do know that my commercial customers have ring circuits installed for the output of static inverters and central battery systems to reduce voltage drop and give redundancy, especially on lower voltage DC circuits.
Car park lighting or large area lighting also utilises ring circuits to limit volt drop and cable size.
Distribution circuits, both LV and HV, utilise various forms of ring circuits, mostly for redundancy.

You would sure as hell see a lot more power cuts if a universal ban on ring circuits was applied across the country

OK fine. For the sake of clarity/pedantry I was referring to a 32A ring final circuit, with 2.5mm live conductors and a 1.5mm CPC, in a domestic/unsupervised situation.

 

[7029 dave]

I like them, because it's ours.Do we really want to go back in time, when 15amp radials were about, with the electric tree growing off it.?
But the modern radials do have their place in some situations. Just MO.

 

[westward10]

Ring final circuits are here to stay like them or not what I really love when testing them are the people who save £5 a year but putting two cpcs through one sleeve, maybe even twisting them together at the same time.

 

[Wes1000]

Ring final circuits are here to stay like them or not what I really love when testing them are the people who save £5 a year but putting two cpcs through one sleeve, maybe even twisting them together at the same time.

Man I hate that!!

 

[andyb]

OK fine. For the sake of clarity/pedantry I was referring to a 32A ring final circuit, with 2.5mm live conductors and a 1.5mm CPC, in a domestic/unsupervised situation.

That's my favourite type of ring circuit.

 

[Hellmooth]

Ring final circuits are here to stay like them or not what I really love when testing them are the people who save £5 a year but putting two cpcs through one sleeve, maybe even twisting them together at the same time.

That is the worst, well that and trying to find both legs in a spaghetti junction mess!

 

[Dave OCD]

It's often much easier to do the end to ends and R1+R2 tests at a convenient socket rather than disconnecting within a 'busy' CU.

 

[valleybilly]

Found an immersion heater on a ring this week with only 2 other bedroom sockets on it . The load was 3kw for the heater and all tests are good so as it was an old install and it was an CU change only . Rings Rule !!!!!!!!!!!!!!! . PS Did reduce the rcbo to 20 amps

 

[davesparks]

Found an immersion heater on a ring this week with only 2 other bedroom sockets on it . The load was 3kw for the heater and all tests are good so as it was an old install and it was an CU change only . Rings Rule !!!!!!!!!!!!!!! . PS Did reduce the rcbo to 20 amps

What's wrong with an immersion heater on a ring? It's been pretty common for decades. I wouldn't do it on a new installation, but see no issue with it as an alteration to an existing install.
Why reduce the size of the ocpd? Was there something wrong with the circuit?

 

[Pat H]

Immersions on rings should be less of an issue nowadays. With modern Central heating people us a lot less electric heaters so ring loading is often less than it would have been when elec was cheap.

 

[westward10]

Is is not ideal to have immersions on a ring final but they are nearly always on the lightly loaded bedroom circuit. Can only assume the 20A was put on because it wasn't switched through a FCU?

 

[westward10]

Immersions on rings should be less of an issue nowadays. With modern Central heating people us a lot less electric heaters so ring loading is often less than it would have been when elec was cheap.

I have two family members who rely on the immersion for hot water.

 

[Midwest]

If your bored, this link debates RFC; The domestic Ring main is it outdated ?Should it be replaced by Radials? - http://www.gadsolutions.biz/electrical-services/ring-main-good-bad

 

[Midwest]

Awhile ago I watched a vid from the Learning Lounge, by Dave Austin (no it's not out on Blue ray) demonstrating testing of a RFC. There was a footnote, that the EU were going to phase out RFC's, can't find a citation for that. But now we have Brexit, we can forget about that

 

[chronyx]

If your bored, this link debates RFC; The domestic Ring main is it outdated ?Should it be replaced by Radials? - http://www.gadsolutions.biz/electrical-services/ring-main-good-bad

Good read, thanks

 

[Pat H]

I'm about to drop power into my new Summer house. Only need 3 double sockets (4mx3m floor area) So had considered 3 radials but its actually easier and less cable to do it as a small ring and at the CU I only have 2 ends to deal with not 3.

 

[Andy78]

I'm about to drop power into my new Summer house. Only need 3 double sockets (4mx3m floor area) So had considered 3 radials but its actually easier and less cable to do it as a small ring and at the CU I only have 2 ends to deal with not 3.

Surely power requirements of expected connected loads play a bigger part in your choice of circuit rather than the number of ends to deal with ?

 

[Pat H]

It will only be low power usage. A computer workstation plus a TV and a few network switches. Probably less than 1KW
Initially no heating for this summer but end of summer a heat pump so that will be on a dedicated feed.
So power isn't an issue. Neat cabling can come into play.
One socket is under the CU the other 2 the other end of the summer house so I'd be running a feed to each anyway. To make it a ring I just connect the 2 end sockets and the first socket near the CU loops one of the legs through it via than direct.

 

[Andy78]

Why not just one radial ?

 

[Pat H]

With all 3 doubles on it?
Or just the end 2 doubles on the radial?
The return ring leg is 6 meters of cable. I'd prefer to drop that in and have it as a ring but radials would work fine of course.

 

[Andy78]

With all 3 doubles on it?

Yes, why not ?

 

[Pat H]

Yes at 2.5mm T&E I'd be limited to 20A but will have a 16A breaker anyway.
I would save 6m of 2.5...
Not sure what's happening yet with under floor insulation but I don't think that will have much impact.

 

[DPG]

A radial for each socket in a summerhouse? Am I missing something here?? Daz

 

[Andy78]

Why a 16A mcb ?

 

[Hellmooth]

Run a 2.5mm for the 3 sockets and stick it in a 20a, or 4mm on a 32a as long as it isn't covered in insulation not going to be a problem.

 

[Pat H]

I have a hot tub coming off the CU in the summer house and need some capacity later for the heatpump.
Don't need more than 16A don't even need that. I'd rather the local 16A breaker tripped should some idiot add 6 electric fire in the future.

 

[westward10]

They are sockets has to be a ring final even if it is just one socket.

 

[Midwest]

RFC were supposedly designed just after or during WWII, because of copper shortage, although other reports/pieces dispute this. But I suppose a RFC at it's maximum design length, achieving an acceptable Zs result. Whereas a 4mm radial, with similar acceptable Zs result, would possibly have to be made from two radials, therefore costing more in materials?

 

[valleybilly]

Is is not ideal to have immersions on a ring final but they are nearly always on the lightly loaded bedroom circuit. Can only assume the 20A was put on because it wasn't switched through a FCU?

\
It was a spur off the ring with no fcu . 16 amp rcbo sorry . It did feed an fcu to some external lights / now disconnected due to faied insulation when connected. Give this man a free xmas tree !

 

[westward10]

Why not put a FCU on the immersion so you can upgrade to 32A.