Twin Mains supply to double socket socket

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
So what happens when an install has been in for years, it’s had its sockets fronts changed a few times, had a few eicrs (PIR for the old school) done and suddenly there is no extra length do you recommend a rewire?
I have seen many broken wires (without them being twisted) in socket-outlet terminals from over tightening of screws. Even some where the terminate screw is on the insulation and not the copper, because not twisted together. In addition, copper eventually deforms under the terminal screw pressure and can become loose. So you first get a high resistance connection, which eventually breaks the ring if the wires not twisted. This is why regular testing recommended, not to fine dangerous DIY mods, but to discover high resistance faults from time passing. However, before twisting, the practise was not to even cut the cable at all, but strip the insulation and fold the bare copper into terminal. So ring was only ever physically broken at the fuseboard. The only reason I can see for not twisting together. Is to keep Testers happy when testing rings, but they are usually not 'Approved Electricians' or 'Electrical Technicians' who should understand the danger. This seems a poor reason for risking the danger of a broken ring. The whole theory behind a final ring circuit is that it cannot be physically broken.

As for the question about rewiring after multiply eicrs. As I previously stated, good practise is to have enough spare wire in box to double back twice before terminating. How many times you planning to change socket fronts?
 
so youre implying that you dont need to test if youve twisted them together. well, except for the bang test.

and id like to see you wire an entire house with a single length per circuit. dont think that was ever a thing anyway. seen the odd socket uncut but never an entire circuit.

you keep getting worse with every comment.
 
Way before my time but have seen neutrals and bare cpcs kept in continuous loops at light switches and the old junction boxes with three inline terminals you could just remove the outer sheath then insulation to create a spur point but never seen it at a socket outlet.
Where are you getting this theory behind a ring final circuit that it cannot be physically broken.
 
This is an interesting debate, so here goes.

The debate is not about currently taught domestic practice where undoubtedly 'twisting interferes with torqueing, testing and fault finding' and logically it would also now require a crimped ferrule to ensure equally good connection of all 'strands' in a simple terminal making future testing near impossible.

If it had been a 'good idea' (and, shamefully I do vaguely remember this being so, along with a spotty face and the Happy Rattles of a Ford Anglia on the way to college) for fail-safe ring completeness then so would twisting together 'without terminal' of any fail-safe 'Earths' you came across (which of course was also once fine in a time when measuring decimal-place ohms in circuit figures were confined to the lab and 'anything a spark could jump would surely be welded into a good circuit in the end'.

Let's not forget that if rings were proposed today they certainly wouldn't get approved . .

Twisting is still 'good practice' in Stranded alarm-cable terminations IIRC but then the terminal torques are hugely less, the terminals often have a flat internal clamp and those wires are fairly easy to tease apart intact

Raise all Shields - Full power :)
 
so youre implying that you dont need to test if youve twisted them together. well, except for the bang test.

and id like to see you wire an entire house with a single length per circuit. dont think that was ever a thing anyway. seen the odd socket uncut but never an entire circuit.

you keep getting worse with every comment.

so youre implying that you dont need to test if youve twisted them together. well, except for the bang test.

and id like to see you wire an entire house with a single length per circuit. dont think that was ever a thing anyway. seen the odd socket uncut but never an entire circuit.

you keep getting worse with every comment.
Judging by your comments and lack of punctuation. I presume English is not your first language and you new to the trade. Since you seem not to understand my point. I never said "you don't need to test". So I don't understand where you got that from. Secondly, original ring-mains had few socket-outlets in a domestic dwelling. One in hallway upstairs and down, with maybe two in living-room and couple in Kitchen. So wiring a ring in one continues loop was reasonably easy. Before that, it was single circuits to each 15A round pin socket-outlets. Very costly in cabling and FB. That was also in the bad old days when you could purchase a BC plug to connect an appliance in to light fittings, such as an Iron. Which extremely dangerous, as light circuits don't have earths then.

A well educated Electrician knows the history of his trade and why curtain regulations now applied. Otherwise, some supposed electricians can be tempted to take shortcuts. Why else do you think there different electrical titles in the electrical world. It because of the different levels of qualifications and education. Once you have a degree, that not from the Internet. You maybe able to contribute to a reasoned debate. Not just throw out insults without any grounds.
 
Interesting debate. I guess 'back in the day' it might have been a good idea to twist, given terminal sizes, But in those days we didn't test like we do today. A megger across the meter tails was good enough to connect to supply. so I guess we now know it was a bad idea. Things move on, including good practice. Given the much improved terminal design of decent socket outlets, switches, fused connection units etc, I see no need. Having done a fair amount of installations, testing, fault finding over the years, it is usually a broken off cable at a twisted connection at a socket that is the problem in the event of a break in the ring. Personally, I think its a bad idea to twist them. As for rings, I am more in favour of 20A radials myself on a new install. But what do I know, only been doing it for 40 years, there's a lot to learn.
 
Twisting.....who remembers copperclad! It's not so much as 'dare not twist' more of a 'date not strip' !

Came actors some a while ago and it had been twisted ( enthusiastically by a retired engineer ) most of the strands had snapped off! BUT if you didn't twist it then tightening the terminal screw cut through the strands for you anyway😂😉
 
For smaller cables, unless each is ferruled, it is good practice to twist the cores together. As you say they tend to come apart reasonably easy without damage.
I installed a Texecom Premiere Elite alarm at my son's warehouse. Ferrules on every core at the panel. More faults than in a Politicians Explanantion of events!...I had run out of my usual ferrules and got some from eBay . What a load of 💩 how on earth can a crimped on ferrule be high resistance??. Must have had 20 plus faults! Ferrules removed and everything was good!

Ferrules were given a Council burial
 
Copperclad should not be terminated through tunnel terminals MK produced a range with clamp type terminals specifically for copperclad.
 
@Speed for one who is by your own admission very experienced and very educated, I would expect you to be able to direct us to your supporting evidence relating to it being a ‘Must’ to twist cables together, if you provide satisfactory evidence then I would be willing to take on board what you say.
I do not necessarily agree with your second point regarding having a degree makes you more clever/knowledgable than those who don’t? Pretty much anyone could go and get a degree which is about the ability to absorb information, however this doesn’t mean that each will go and apply this new knowledge nor necessarily understand this new knowledge to know how to apply it. Practical experience can give just as much relevant knowledge if not more so than a degree. Some may also learn better by practical experience than text book knowledge?
As for the twisting debate, I suspect that it was more of a necessity with the old stranded cores than it is with the solid core, to gain a good contact?
 
What a load of 💩 how on earth can a crimped on ferrule be high resistance??.
Cheapo Ferrules usually lose their shine fairly quickly so I think they use a bit of oil or lacquer to keep them shiny until some mug buys them at '10p /1000 plus £5 postage from China '.

They are something I am very picky about sourcing, as unless the material and finish is correct and it behaves correctly in the matching crimper and terminal I believe the end result is going to be worse than no ferrule at all.

Seen hard work crimping, higher than expected resistances, and ferrule material actually cracking and twisting when tightened (normally !) in a terminal.

No one needs yet another layer of doubt in an installation 😂
 
Playing Devils advocate here.....how can you cricise @Andy™ punctuation? You need to check your own first, along with grammar and spelling

And what are 'curtain regulations'?

Just saying
You make a valid and good point. I see the mistake now. Lol.

Yes I do use a spell and grammar checker as I'm Dyslexic. However, it doesn't always pick up every mistake. But despite my handicap which was diagnosed in 1960. I've always manage to achieve credits or distinctions in all my electrical exams and submissions. I even have B-TEC Mechanical qualifications too. And that was long before people like me got help at colleges. I just had to work twice as hard as everyone else and have a good memory. As I spell by remembering the shape of each word, not the letters. However, the best Electricians I worked with are either slightly Dyslexic, OCD, or a little of both. It allows you to find faults on complicated control systems as mentally view circuits from both ends. It a bit like seeing the green lines of code for the first time in the film Matrix. Whereas as most people start at one end (i.e. power source) and just follow it through. However, it's a lot quicker to work backwards. Since by starting at the beginning means you will follow many branches that not related to fault. And if OCD, you tend to check your work many times which eliminate most errors before testing. Whether that is in your wiring or programming.

Thanks for pointing out my typo. Lol. :)
 
Cheapo Ferrules usually lose their shine fairly quickly so I think they use a bit of oil or lacquer to keep them shiny until some mug buys them at '10p /1000 plus £5 postage from China '.

They are something I am very picky about sourcing, as unless the material and finish is correct and it behaves correctly in the matching crimper and terminal I believe the end result is going to be worse than no ferrule at all.

Seen hard work crimping, higher than expected resistances, and ferrule material actually cracking and twisting when tightened (normally !) in a terminal.

No one needs yet another layer of doubt in an installation 😂
I suppose it depends if they using the correct manufacturer's crimping tool. I seen a lot of people use the unapproved scissor type tools you get from Car Shops. I even seen people use Plyers or Cutters. However, as I hope you all aware. None of these methods conform to the requirements for an electrical crimp. It poor workmanship that causes problems, not crimping. A proper crimping tool actually cold welds the copper wire (or Aluminium if above 16 sq. mm) to the crimp. If crimped properly, when you hacksaw through crimp. You will not see the join.

However, most sparks don't or won't invest in proper crimping tools, as the can be hundreds of pounds each. With each crimp type requiring its own tool. You can easily rack up £1k buying 5 or 6 proper manufactures crimping tools.
 
You make a valid and good point. I see the mistake now. Lol.

Yes I do use a spell and grammar checker as I'm Dyslexic. However, it doesn't always pick up every mistake. But despite my handicap which was diagnosed in 1960. I've always manage to achieve credits or distinctions in all my electrical exams and submissions. I even have B-TEC Mechanical qualifications too. And that was long before people like me got help at colleges. I just had to work twice as hard as everyone else and have a good memory. As I spell by remembering the shape of each word, not the letters. However, the best Electricians I worked with are either slightly Dyslexic, OCD, or a little of both. It allows you to find faults on complicated control systems as mentally view circuits from both ends. It a bit like seeing the green lines of code for the first time in the film Matrix. Whereas as most people start at one end (i.e. power source) and just follow it through. However, it's a lot quicker to work backwards. Since by starting at the beginning means you will follow many branches that not related to fault. And if OCD, you tend to check your work many times which eliminate most errors before testing. Whether that is in your wiring or programming.

Thanks for pointing out my typo. Lol. :)
Not being able to spell doesn't make you disabled,
Don't play the victim ,

Not answering my last post about NOT twisting RFCs or RMs is just picking and choosing what you don't understand or can argue about.
Seems you just want to pick flaws for no good reason.

Either back up your claims with well founded, relevant, up to date info, or don't bother putting your ill informed (imho) opinions out there.
Perhaps you need to rethink your methods now we are in the 21st century with different technologies.
 
I don't care whether you are dyslexic or a monkey's uncle it is not relevant to your initial post because let's be honest, you came on here derating people's methods and as of yet you still haven't stated where it is stated you MUST TWIST CONDUCTORS.
 
Top