Ring-Ring, answer please!

sparksburnout · Jul 30, 2014

Got an odd set up in a Kitchen, which just seems wrong but I can't convince myself why its wrong, other than bad practice. There is a final ring, serving 4 outlets on one side of the kitchen, which is then spurred, using 6mm, to another, small ring with 3 outlets. Previous installer obviously used a redundant cooker feed rather than running new. Now, I do intend to rewire it conventionally, but what exactly is wrong with it? Only thing I can find is that each circuit should have it's own PD, but it's only one circuit really? And even if it is classed as 2 rings, there is nothing to say they couldn't be fed off the same PD, even if it's a c**p idea. Surely the 6mm is just acting as the parallel conductors of a ring, it can quite easily handle the max load the PD will allow?

Pete999 · Jul 30, 2014

So to get this straight you have two small RFCs joined by a length of 6mm, is that correct?

Engineer54 · Jul 30, 2014

Pete999 said:
So to get this straight you have two small RFCs joined by a length of 6mm, is that correct?

That's exactly what he's saying... lol!!

Pete999 · Jul 30, 2014

Engineer54 said:
That's exactly what he's saying... lol!!

Just trying to get the facts, no need for sarcasm lol

sparksburnout · Jul 30, 2014

Pete999 said:
So to get this straight you have two small RFCs joined by a length of 6mm, is that correct?

Yep, thats correct.

malcolmsanford · Jul 30, 2014

A lollipop ring taken a step further. I'm trying to get my head round this . The 4 socket ring i gather is wired back to the DB in a conventional manner. I then take it in a socket / JB you have 2x 2.5mm and then a 6mm over to a 3 socket ring which again will have 2x 2.5s and a 6mm going into sonething. If that is right fair play to the lad/lass for terminating that in a box

Richard Burns · Jul 30, 2014

SO you could overload one section of the first ring as the whole load of the secondary ring will be concentrated at the point of the spur.
Though you could also get the same effect by loading a ring unevenly, it is just easier for it to occur this way.

sparksburnout · Jul 30, 2014

malcolmsanford said:
A lollipop ring taken a step further. I'm trying to get my head round this . The 4 socket ring i gather is wired back to the DB in a conventional manner. I then take it in a socket / JB you have 2x 2.5mm and then a 6mm over to a 3 socket ring which again will have 2x 2.5s and a 6mm going into sonething. If that is right fair play to the lad/lass for terminating that in a box

The "extension" ring is wired off a JB to the 6mm. I have not been able to look at the connection at the "main" ring yet, but I am assuming it is done in a similar fashion, as it would be pretty tricky to get 2 x 2.5 and 1 x 6mm into a socket I reckon. The "main" ring goes conventionally to the CU on it's own PD, yes. Odd aint it?? You just want to say No! but I can't see whats wrong with it! Richard makes a good point about overloading one side, but surely if it's in a proper JB it will handle the max current the PD will allow.

Richard Burns · Jul 30, 2014

Pretty picture

[ElectriciansForums.net] Ring-Ring, answer please!

you are only permitted to run one double socket on a spur for this reason.

sparksburnout · Jul 30, 2014

Richard Burns said:
Pretty picture
View attachment 25733
you are only permitted to run one double socket on a spur for this reason.

I can see this Richard, and you, as usual, make perfect sense. However (lol), I realise the reg's can't be installation specific, and if the spur on the "main" ring was off the centre point, which I suspect it is, then the load would be spread evenly? It's still a c**p way of doing it especially as the cable run is dead easy to make it into a proper ring so I am going to rewire it. Just a further point that arises from this, then, which I am now a bit confused about. I understood that the limit of one single or double socket on a spur was to protect the single bit of 2.5mm forming the spur. Is it in fact to do this and to make sure the ring is not overloaded as described here?

Richard Burns · Jul 30, 2014

The load on a ring should be evenly distributed to prevent potential overload of the ring cabling and putting in a multipoint spur will concentrate the load. As you say at the midpoint should not have a lot of effect.
The limit on the one socket outlet I would say is primarily to avoid overloading a 2.5mm² cable but also to prevent ring concentration, otherwise presumably they could have a regulation permitting more sockets if the spur cable was 4mm², but this does not exist.

Yeah, overall, rubbish and very odd way of installing, rewire to single ring and all is OK.
The multifarious ways people can mess things up is always amazing!

malcolmsanford · Jul 30, 2014

Could you have 1st leg of your ring going into the 1st socket of the 4, then looping has normal to the 4th socet, you are then left with one leg of the ring and your 6mm at that socket
6mm then goes over to your 1st socket of the 3 sockets where you continue your ring and the last leg of the ring leaves the 3rd socket back to the board
In essecence that 6mm is a leg of the ring, just saying like.

Knobhead · Jul 30, 2014

sparksburnout said:
Got an odd set up in a Kitchen, which just seems wrong but I can't convince myself why its wrong, other than bad practice. There is a final ring, serving 4 outlets on one side of the kitchen, which is then spurred, using 6mm, to another, small ring with 3 outlets. Previous installer obviously used a redundant cooker feed rather than running new. Now, I do intend to rewire it conventionally, but what exactly is wrong with it? Only thing I can find is that each circuit should have it's own PD, but it's only one circuit really? And even if it is classed as 2 rings, there is nothing to say they couldn't be fed off the same PD, even if it's a c**p idea. Surely the 6mm is just acting as the parallel conductors of a ring, it can quite easily handle the max load the PD will allow?

If they’ve used a redundant cooker feed to create a lollipop, where does the link to the first ring fit in?

7029 dave · Jul 30, 2014

Are we talking interconnection between 2 RFC's ?.

sparksburnout · Jul 30, 2014

Tony said:
If they’ve used a redundant cooker feed to create a lollipop, where does the link to the first ring fit in?

I didn't mean they had kept the original connection that the 6mm cooker cable would have had, I meant they had used the existing cable to link the 2 rings, obviously. Not to worry, Richard has cleared the mist on this one earlier......