Ring or spur

GM228

Hope this is the right place to ask.

Is it safe to assume that all sockets (as built) in a house would (or should) be on a ring or are spurs ever taken off a socket for a new build (such as an after thought or shortcut - against regulation??).

When taking off the socket is there an easy way to tell, I would assume each ring would have two live/negative/neutral on each socket to complete the ring as opposed to one which would normally be an indicator of a spur.

Any advice appreciated.

aido79

GM228 wrote: »

Hope this is the right place to ask.

Is it safe to assume that all sockets (as built) in a house would (or should) be on a ring or are spurs ever taken off a socket for a new build (such as an after thought or shortcut - against regulation??).

When taking off the socket is there an easy way to tell, I would assume each ring would have two live/negative/neutral on each socket to complete the ring as opposed to one which would normally be an indicator of a spur.

Any advice appreciated.

Your terminology is wrong. In general the only place a ring circuit would be used is in a kitchen. A ring circuit is a circuit which goes from the mcb to the first socket and then to the next through all of the sockets on the circuit and then back to the mcb.

What you are most likely asking about is a radial circuit in which the only difference is that the circuit stops at the last socket on the circuit.

A spur will easily be identified by removing the socket from the wall and checking to see if there has been a third cable(live,neutral and earth) added to the wiring for the radial circuit.

electrichunter

ring circuits are not allowed in kitchens any more.

Risteard81

electrichunter wrote: »

ring circuits are not allowed in kitchens any more.

Not actually true. There is merely informative guidance about this in an Annex to the Rule book. As it is not normative it does not form part of the Rules.

Indeed RECI asked the ETCI to withdraw the rule as they felt there was no logic suggesting that a ring final circuit is perfectly fine elsewhere but that it mustn't be used in a kitchen. If it is correctly designed so that loads will be distributed around the ring evenly then there is no danger. ET101 does not permit unfused spurs to rings, however, although other standards (e.g. the IET/IEE Wiring Regulations) do.

Tuco88

I think the logic was that in a domestic kitchen it was more common and a greater chance of people taking a spur/tapping into a ring circuit. More so if it was a house from 70/80s that was designed with very little outlets where as today you cant have enough.

Im not really a fan of ring circuits but everything has its use.

Its a better job to balance out the area with radials and sole circuits (Dryer,fridge etc...)

Risteard81

I have to say I am a fan of ring final circuits, as it is far more efficient with cable. But really the thing to do is design each installation on its own merits (whether that mean rings, radials or a combination of both).

Bruthal

Tuco88 wrote: »

Im not really a fan of ring circuits but everything has its use.

Its a better job to balance out the area with radials and sole circuits (Dryer,fridge etc...)

Yea i am not a fan myself.

aido79

GM228 wrote: »

Hope this is the right place to ask.

Is it safe to assume that all sockets (as built) in a house would (or should) be on a ring or are spurs ever taken off a socket for a new build (such as an after thought or shortcut - against regulation??).

When taking off the socket is there an easy way to tell, I would assume each ring would have two live/negative/neutral on each socket to complete the ring as opposed to one which would normally be an indicator of a spur.

Any advice appreciated.

Back on topic...why do you want to know this?

2011

Bruthal wrote: »

Yea i am not a fan myself.

Me neither.
The circuit will still function without it being apparent that either the phase or neutral is disconnected / broken at any point on the ring. This can result in a 2.5 mm sq. conductor being “protected” by a 32A MCB. Obviously this MCB can not provide sufficient protection.

I haven't see them being used on industrial in a long time. Having worked only on industrial installations outside of ireland for the last 4 years I haven’t seen any ring circuits abroad either.

Bruthal

2011 wrote: »

Me neither.
The circuit will still function without it being apparent that either the phase or neutral is disconnected / broken at any point on the ring. This can result in a 2.5 mm sq. conductor being “protected” by a 32A MCB. Obviously this MCB can not provide sufficient protection.

Yea I think they were a sort of one size fits all, type solution in the past. A house with 10 or 12 outlets in total, ring main for the lot, no thinking or design needed. Tucos post earlier put it well...

Its a better job to balance out the area with radials and sole circuits (Dryer,fridge etc...)

I never liked the idea of closed loop final circuits for the reasons you mention there 2011. And someone comes to change an MCB, hmm, maybe i`l put in a new one and not have 2 circuits in the one breaker, or something like that. If a connection becomes bad, or open, it should be showing itself, not staying hidden indefinitely. Id say a good many old ring mains are actually unintentional radials at this stage.

I haven't see them being used on industrial in a long time. Having worked only on industrial installations outside of ireland for the last 4 years I haven’t seen any ring circuits abroad either.

Id be surprised if any industrial or commercial designer would want them, im doing all the finals in a well known place at the minute, and would be run out of it if ringed the sockets.

Stoner

I haven't seen ring circuit used in kitchen in Ireland in a long time. Usually it's too radials.
UK is a different story.

GM228

Thanks to all for the replies.

aido79 wrote: »

Back on topic...why do you want to know this?

I'm looking to add existing sockets in two locations and was told that adding a spur to an existing socket which was already a spur is a big no no.

(I got mixed up with the ring/radial setup)

2011

GM228 wrote: »

I'm looking to add existing sockets in two locations and was told that adding a spur to an existing socket which was already a spur is a big no no.

(I got mixed up with the ring/radial setup)

So it is a radial circuit?
How many sockets are on this circuit?
How many and what type of rooms does the circuit serve?
What is the rating and type of MCB supplying the circuit? (B type 20A for example)
Is the socket circuit protected by an RCD?

It might be possible to add two additional sockets.

GM228

2011 wrote: »

So it is a radial circuit?

That is my understanding.

2011 wrote: »

How many sockets are on this circuit?

9.

2011 wrote: »

How many and what type of rooms does the circuit serve?

3 bedrooms.

2011 wrote: »

What is the rating and type of MCB supplying the circuit? (B type 20A for example)

I'll have to check.

2011 wrote: »

Is the socket circuit protected by an RCD?

No.

Risteard81

GM228 wrote: »

2011 wrote: »

Is the socket circuit protected by an RCD?

No.

Are you sure? A Registered Electrical Contractor would be obliged to issue a Notice of Potential Hazard if that was the case and they spotted it and were not in a position to rectify that on the spot.

2011

As there is no RCD my advice would be to get a registered electrical contractor in ASAP to rectify.

Strictly speaking a socket circuit should not supply more than 2 rooms (a hall dose not count as a room). The limit for a radial socket circuit is 10 double sockets.
The bigger issue is the lack of RCD protection.

You should not add to a circuit that has strayed this far from the regulations in my opinion.