Leading on from the "Wiring plugs" thread;
In the UK domestic circuits are usually "ring".
In South America they are usually "radial". (like a spur in the UK).
A ring is regarded as safer in the UK since it incorporates two wires to every socket reducing the demand upon the wire itself.
A ring does potentially conceal problems from such things as accidental cross wiring. However, if it is done correctly, there are no downsides to a "ring" approach.
Are there any other factors which I have not thought of which would cause me to lean harder on a contractor to change his approach rather than just letting him get on with it?
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>> Are there any other factors which I have not thought of which would cause me
>> to lean harder on a contractor to change his approach rather than just letting him
>> get on with it?
>>
Are there electrical installation regulations and inspections ?
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In that case you can fit whatever you like, but why go for what would be an unconventional setup for your location?
Last edited by: Old Navy on Sat 6 Dec 14 at 16:09
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>>In that case you can fit whatever you like,
I know. That was not my question.
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A ring is better FMR, because it's much less likely to suffer from overloading resulting in the cables getting hot, sometimes melting their insulation and causing a short which might spark and start a fire. I don't know about people's habits where you are, but what with all the products available people often have christmas trees of plugs stuck in every socket, and at busy times much current will be used (dishwashers, washing machines and anything else involving a motor of any size are particularly demanding). Doubtless you know all this being a, er, switched-on sort of chap.
I put a ring main in myself on our two floors in the grove. Ages grovelling under floorboards and finding infestations of woodworm and dry rot when I had other things on my mind. The electrician the council made me pay to check my work was quite polite. His only complaint was that I had left twists in the cable here and there, when a proper job would ensure it was all lying flat and secured to one wooden joist/beam or another. It doesn't take a huge amount of brains of course, there being only three wires, but it does take a lot of energy and a certain manual ingenuity. You have to chop steel boxes into the walls and through skirting boards, and the fittings cost a few bob. MK were the best in those days, well worth the extra money.
I wouldn't undertake anything like that now. 'Ah pays to have that s*** done,' as the wife-abusing black dockworker Abraham, who spends all his wages on his black Cadillac and 'brownskin' good-time girls (in Hubert Selby Jr's novel Last Exit to Brooklyn), tells himself with pathetic pride when he sees more practical, realistic neighbours washing their own jalopies.
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I think a ring is better AC.
But the choice I face is this;
1) The electrician does what he is used to doing, and I guess he's more likely to get that right. But it will be a radial circuit.
2) The electrician does what I want, which is I think a safer way, but he might muck it up.
Hence the question, are there any implications beyond load on the cable?
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>> are there any implications beyond load on the cable?
Depends on what the regulations (if any) are where you live. In the UK they are, or were 30 years ago, very comprehensive and strict. Up to a point also on the size, layout and structure of your house. If it's all stone walls and stone floors the wiring more or less has to be on the surface, difficult to hide therefore and potentially unsightly.
I wouldn't think a professional electrician could muck it up by crossing positive and neutral wires or making the earth wire live. They test their installations and ensure that they are safe.
Small things can cause trouble later. A grub screw not properly tightened in a socket or junction box (one needs a lot of those) may spark in a very small way initially... then the sparking eats away a bit of brass or copper over time and becomes worse, causing symptoms well short, it is to be hoped, of a house fire.
If you catch a whiff of burning or overheating plastic, follow your nose to the place.
Last edited by: Armel Coussine on Sat 6 Dec 14 at 16:29
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I've found that somehow the grub screws can loose their grip and a subsequent visit some years later allows a small amount of tightening. I've seen wires twisted together before being pushed into their hole and untwisted wires. My mate who was a Navy marine electrician but lost qualification with the introduction of subsequent regulation insists the wires go in untwisted as the grub screw pushes everything together nice and tight.
I think the advantage of a ring is that a device that creates a high load is pulling its electricity in from two directions thereby reducing potential for heating the circuit particularly if there are several high consumption items drawing from the ring.
I'm no electrician but as I have worked through the property have added many extra double sockets within the ring to facilitate unlimited choice of places where items such as table lamps can be plugged in. I have 8 within the living room. The only issue is getting access through a chipboard floor and of course digging in the steel boxes. But when you are doing a complete makeover including skirting it might as well be done. Likewise my surround sound system has all the wires under the floor with wall sockets for connection.
Mind you when I got it all buttoned down and a new TV installed I realised I should have also run an ethernet cable to the router so had to use one of those adaptors that work through the mains.
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Am I right in thinking that rings are becoming out of favour in the UK now and a lot of modern rewires tend to use radials?
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When I re-wired the lounge at Teddy Towers...removing old sockets from skirting boards and fitting them in the plaster, stuff like that, I put in a small ring main with a single gang socket in each corner of the room.
That circuit is controlled through one half of the 2 gang light switch and means the three table lamps and the display cabinet can be switched on as a job lot. Wired to 5 amp in the consumer box. The only item used in the lounge extra to the usual stuff is the vac...and we use the hall socket for that.
The garage has it's own rings for lights and power. It has it's own unit with RCDs.
I was given a couple of dozen new MK sockets, both single and double, by a pal clearing his garage. All new stuff in it's packets...half of them were no use 'cos the factory had tightened up the wire grip screws far too tightly to be undone by a screwdriver.
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I've had that problem before with MK sockets, had to return one because the screw would simply not unscrew. It is a shame as I find their light switches to be of excellent quality and use them all over the house.
Still got an old fashioned six way Wylex fuse box here, it is 35 years old and probably will still be in service in another 20 years time! I can't convince my parents to get it upgraded, but also I know there will probably be a lot of remedial work required before that is done such as earth bonding. I did upgrade the old 4mm bonding in the kitchen to 10mm stuff when I ripped it out earlier this year.
Last edited by: RattleandSmoke on Sat 6 Dec 14 at 17:21
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>>Still got an old fashioned six way Wylex fuse box here, it is 35 years old and probably will still be in service in another 20 years time!
Wylex make RCDs that fit the old fuse connections about £7.00 each and a safety upgrade not needing an electrician!
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>> Wylex make RCDs that fit the old fuse connections about £7.00 each and a safety
>> upgrade not needing an electrician!
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Easy to do !
When I did this @ my daughters flat the lid was already marked out with moulding lines where to cut hole for the RCDs.
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>> Are there any other factors which I have not thought of which would cause me
>> to lean harder on a contractor to change his approach rather than just letting him
>> get on with it?
The contractor will make a better job of something he knows
The infrastructure components available to him are designed to work with that system
Any subsequent fault finding will be easier with a system the contractor knows
Any future additions / building work /electrical work will be easier with a system they know.
Having a ring main is really not that much enough of an improvement to force a different system and way of working on the resources you have.
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"Having a ring main is really not that much enough of an improvement to force a different system and way of working on the resources you have"
Exactly how I am thinking; I just wasn't sure if there were more significant factors plus or minus, about rings vs. radials that I did not know.
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"I just wasn't sure if there were more significant factors plus or minus, about rings vs. radials that I did not know."
Unless you want to live out the rest of your life in that particular house, there's a fair chance that you may wish to sell it one day. If it were wired-up in an unconventional way (compared to the locals), might that make it less attractive to a potential purchaser?
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A reasonable point, but here it will make no difference one way or the other.
And no, whilst I may well rent it out, I doubt it'll ever be sold.
I guess safety and reliability are my main concerns.
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>> Having a ring main is really not that much enough of an improvement to force a different system and way of working on the resources you have.
That's all good shrewd sense. If the electrician thinks of cutting corners he should discuss it with you first putting the pros and cons. But Zero's right, he'll do a better job left to himself, and with less stress all round.
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A ring uses less cable, and may make for a neater arrangement because it can just loop round the house rather than needing lots of cables radiating from a central point.
So the size of the house might be a factor.
Presumably the spreading of the load in a ring could be similarly achieved by using thicker cable in radial form, but that too would require more material.
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Wiring circuits - Old Navy
