And like you has a brilliant, pithy sense of humour!

Sure that's a module on their training course

Like painters fill door hinges.

Whenever my plasterer friend does any plastering in my house I always get him to overskim the edges of the box with the skim coat and then when it's dried I carefully cut it back with a stanley knife right in line with the edge of the box and it doesn't take much effort to just put a short faceplate screw into the lugs on the box to stop them filling up with skim coat then just give it a suck out with a plastic vacuum cleaner pipe with the circuit breaker switched off

At least yours bother to leave a cut out.

I was taught as an apprentice to be polite and ask them try to not to If they overdo deliberately after that, discretely leave tiny gravel pieces in their bags of plaster. Tut tut tut.

I always do this even though I dont bother fitting an earth to the back of sockets

@@antrobuselectrical554 depends whether the box is below or at your height! If box is situated high (I know, that's unusual!) then it might be appropriate to have the earth terminal above so that one can get a better look at it and connect to it.

Correct in the main however I had a situation where I had to use one of the biggest sized knockouts this was because I had a a few cables that had to fit through as it turned out I had to put the box with the CPC Terminal upside IT'S rare but can happen! Best wishes Warren

I also run the CPC loop to the backbox with a link to the socket for the same reason

Or as can happen the m3.5 mounting tabs detach.

Do you install fly leads to all metallic consumer unit covers in case someone takes the cover off while the board is live? Or what about metal conduit box lids? Both examples, in most cases relying on a screw as an Earth. Same as a socket back box. So what’s the difference? The likely hood of it being open while live I suppose? We have to draw the line somewhere.....the regs take into account finished installations when it comes to things like this. There is no requirement to consider part finished installations. I’ve never ready anything in the regs to say ‘must make provision for earthing for when the user exposes live parts during decorating’! Lol! A socket hanging off the wall isn’t a finished install! And therefore should not be live! If it isn’t live......why the need for earthing the back box with a fly lead? Let’s not talk about ‘in the real world’ either.....it’s in the real world that unqualified Wolly’s take sockets off to decorate, leave them hanging there for days and then just screw back without checking the terminal tightness! Possibly leading to fires! Tip for them.....leave the sockets in place, where the back box is earthed, and the connections are sound. Or employ an electrician to take them off safety so you can do your work. 3rd option.....fool around with it yourself! Just don’t expect me to make allowances for such stupidity while I am initially installing it! Lol! Anyway.....it’s been a long day! 😂

​@Mr Brightside my thoughts exactly ...Whilst some might not live in the ' real world' the rest of us sparkies do ...no body calls a sparkie to wall paper ...although I've been called to sort out tripping MCB's in the aftermath ..several times because original installer didn't use a grommet and the Home owner pulling on the cables shorted to the earthed BB...so hmmm I think I 'll keep adding a cpc strap to the BB ;) I cant help but imagine someone tucking some wall paper under the loose socket and touching a live BB ..I know we shouldn't and dont have to take that into account at the design or install stage ..but Personally I think we should try. I'd bet even K C adds the BB cpc if he's installing in a loved ones home. plus if you get into industrial electrical work then the vast majority of removable conductive covers are supplied earthed with a seperate conductor ..not just relying on the 'screw'. not the round conduit covers though ....dont give them idea's....and i'm not having the seperate cpc argument again. I like to afford domestic customers at least the same protection where possible as the industrial ones ...preferably more ...even if it costs me a few meters of cpc per year.

@@Spark101. The brass BB terminal is included in manufacture, one would assume for a good reason - like earthing the zinc-plated BB and giving protection to the exposed fixing screws. Of which, as we see in John's demonstration, always come with one fixed and one loose female threaded lug. The loose lug would, by definition be a poor electrical connection, but often, even the fixed lug, can have issues, like zinc flashing causing a poor threaded connection, I've even come across fixed lugs being loose themselves, or poorly threaded. So as the maxim for anything potentially dangerous is - safety first, the BB lug, if fitted, should *always* be hooked up to the CPC. . // We have to draw the line somewhere... // Presumably that means cutting cost and time at the risk of safety. I would also argue, laziness... . Yes, there are plenty of *uneducated* people doing electrical work. However, the matter of qualifcation is overused, especially by electricians themselves, who with the odd exception - like John here - tend to be overly secretive about divulging their 'hard-earned' arcane electrical installation knowledgte to those - 'not in the club'. In reality, electrical installation is fairly elementary, providing one adheres to correct conductor size, voltage drops, to the circuits power requirements and understands the practical aspects (tool and equipment usage) thoroughly. It aint rocket science. Anyone who has trained in electronics can easily cope with domestic mains circuit installations. I wire sockets exactly like John here... *You'd* be hard pressed to know difference. . As for decorators, most pro decorators I know (and those not so pro, who I've advised....) don't remove the appliance socketts from the wall, but merely loosen the fixing screws enough to create a gap around the socket to paint around. This way, the rear and potentially dangerous part of the socket remains relatively guarded, with the CPC intact... Especially if the BB tail is included. And no screws get lost in the process. This can be done without necessarilly powering down that circuit, though wherever possible, I always advocate doing so as an extra precaution, depending on the installation and other domestic factors like - roaming kids, with screwdrivers... . Though I'm trained in Marine Radio and Radar Engineering, I do not have full electrical qualifications, (I do have PAT and 'mains compliance' installation, certification) but I can still perform a full professional installation, from initial electrical schedule design to final fix. I am self-educated and experienced and always refer to the latest edition of IEC/IET regs and other relevant documentation. As such, I've been trusted to undertake electrical installations, which have subsequently been examined by a 'qualified electrician' with zero faults or criticism. I even undertook (one of my first jobs...) the entire wiring schedule and installation of an 'Arts Centre' - a 17th century *public building* - that was upgraded to three phase and expanded to include a 60 seater cinema and extra gallaries. This installation also included a residence and restaurant. So that installation was pretty comprehensive. My schedule schematic of each of the four storeys of this ancient listed building was subsequently passed by the regional electrical provider and local planning body and was approved with no alterations or recommendations, other than the removal of certain parts of the orignal installation. I was 23 years old (15th/16th IEC regs). I didn't do the final testing, or hook-up, which was undertaken by council electrical contractors. The installation passed and, as far I know, is still in business. . You are a qualified wally, who choses to forgoe safety by not bothering to wire in a BB CPC tail, all for the sake of saving a few minutes or pennies... Who of the two of us, is actually the safer electrician? . Yes... I suggest you had better go and have a beer...

Niceic even say you should

It's 410.3.9 (iii) and I've been looking for that regulation number for yonks. It's a quirky one and counter-intuitive but I see it as a good example of common sense being applied in the regulations.

You forgot to mention, it's also a single socket just to increase the "pain in the arse" factor

And set back under a kitchen cupboard for maximum contortions.

You'd stop liking it so much if you had to produce the tooling & specify the materials to actually make round back boxes in any material other than plastic. Rectangular boxes are much cheaper to produce. Plus the specification dates back to when electricians used a bolster (chisel) & lump hammer to recess them, & those aren't as good at producing neat round holes as they are at rectangular.

@@beardyface8492 Drilling a round hole with modern drills is *easy.*

@@johnburns4017 Indeed it is, but then so is sinking rectangular ones with the correct tool, & changing would require all new design outlets & switches too. Then if adopted you'd never know in advance which of two standards you'd be working on, & have to keep tools & stock of both types. Sounds like a worse situation than the current one if you ask me.

@@beardyface8492 I think you are just being argumentative for the sake of it. It is plainly vastly more work to create a square hole in just about any material you can name. The amount of time, dust, noise and aggro involved in installing a square box in anything other than a hollow plasterboard wall completely and utterly dwarfs any consideration over the cost of producing a round box, even in metal. Have you noticed that you can buy a tin of beans in the shop for approximately 20 pence? Not only does this low price wangle you almost a pound of delectable haricot beans in a mouthwatering tomato sauce but included almost as an aside is an ingeniously manufactured cylindrical steel container.

@@nobodydoesithalfasgoodasyou The point that the standard was created back when recesses were sunk using unpowered hand tools (hammer & bolster) remains, as does the second point if you introduce a new standard.. you suddenly then never know which you're dealing with & need two sets of tools.. Plus there's the awkwardness of dual-gang sockets & switches, which you simply couldn't design with a round back-box.

Twisting cables together makes it a pain in the arse for testing, you may have to un-twist them which usually ends up weakening the copper too much, leading to breaks in the conductor or high resistance connections if its not spotted. I cant remember the specific regulation at the moment but our regs say that each conductor should be connected separately

I only twist if I’m trying to get 3 wires in a difficult spot, otherwise I don’t bother

I was taught that as well but in the UK these days it's sometimes necessary to seperate the wiring out behind a socket for electrical inspections so it's not done at the moment. No doubt in another 10 years time they'll make it mandatory to twist the wires together, they are like that in the UK.

I’m not keen on solid core wires being twisted together. If the screw terminal is tightened too much, it will bite into one of the copper solid core wires more than the other. Then should you need to untwist it at a latter time/date, there is a high chance of a fatigue fracture and the solid core breaking. If it happens while you are working on it, it’s a pain to strip more insulation off. If the wire is now too short, it’s a right pain in the arse. But worse, if the wire breaks later and it’s not noticed, then when you test the circuit, you waste time chasing the resulting open circuit fault.

Same for me on the twisting together. I was told off about doing it a few years ago (I think on the basis that it could make future fault finding difficult?) so not done it since. Twisting seemed a good idea to me.

Twisting solid core conductors is not a good idea in my opinion as they break off so easily.

Twisting is better in my opinion as well it would provide a more uniform filling technique for the recessed holes, no guarantee of course it works every time. It’s still worth checking.

Math Man - not keen on solid core wires being twisted together. If the screw terminal is tightened too much, it will bite into one of the copper solid core wires more than the other. Then should you need to untwist it at a latter time/date, there is a high chance of a fatigue fracture and the solid core breaking. If it happens while you are working on it, it’s a pain to strip more insulation off. If the wire is now too short, it a right pain. But worse, if the wire breaks later then when you test the circuit, you waste time chasing the open circuit fault.

I've never understood the concept of "well its not needed so I won't do it". If there is an earth terminal, or just an empty loop terminal on a plastic appliance, and you have an earthing conductor, why not install it anyway? Its 10 seconds extra work, but it keeps them from flapping about, and has a back up in case the main protection (usually "unable to be touched") fails. I have yet to hear a convincing argument of why you'd skip that part because the regs allow it, other than saving time. So, time/productivity is more important than safety, and you'll cut whatever corners you can? Thats a great way of making a mistake when conditions change, or when regs change, and you still rely on muscle memory, and relies on a lot of assumptions which might not always hold true.

A lot of people get confused by regulations, which state only the minimum requirement, and think they instead state best practice and assume they then don't need to do anything extra. And this applies to most standards and regulations, not just BS7671.

I think it comes down to whether you feel something is necessary and if you have the relevant experience and common sense then you can make this judgement.

“Good practice” - generally used as an excuse by electricians not to keep up to date.

They are used in the U.K. quite extensively, it’s required for UKCA when shipping a product with stranded wire inside for example. (some exceptions such as ultrasonically bonding the wire is deemed ok too)

@@akbarramzan7436 That's good. Here in the USA, we use crimp terminals for particular types of terminations like forks, rings, spades, etc. But what you NEVER see here are the ferrule type for some strange reason.

That’s because it’s not a big deal

@@w415hyz Unless you fit metal switchplates on a wooden back box!

Fixed lug - is no more rated as an electrical conductor as the loose lug ! Having installed a cooker at a friend's when he moved to a flat - and found the earth used to be via conduit, I'm not going to use anything but copper (or brass) conductors for earthing.

It's dry humour as water and electricity doesn't mix.

Oh no, that would be far too easy. Plus it would spoil the fun of going round tightening all the loose terminals during an EICR

Flauschlab well I can’t say about domestic but the industrial ones do fail quite often, just my experience.

@@dogwalker666 might be due to the push-in terminals for industy are made out of chinesium.

@@nightshadelenar that would not supprise me klippon and entrelec are not as good as they used to be.

And ruin the fun of hunting lose neutrals? Pft

I.S. 201-4 cable is not to a British Standard though. Being in Ireland, and within a mile of the border, I use plenty of both types of T&E. But I never bring either type of T&E across the border from where it is intended to be installed. Incidentally, in the south of Ireland, it is mandatory to connect a flylead to the backbox and you are prohibited from relying on the connection through the screws to the lugs.

I sleeve it long and bend it over so nothings exposed and the sleeve holds on, call me tight but I wouldn't waste a wago on that!

Just cover it with insulation ?

There's some interesting calculations you can do there, the thing is, for a given cross section, yes copper is a better conductor than steel, but once you factor in the comparatively massive cross sectional area of steel tube, you suddenly find that steel conduit has a considerably lower resistance than any earth lead you're likely to run inside it, I'm sure I even saw a video where JW did the calculations. Why add the expense of more wires & the labour of pulling them when they're not required? It'll take a hell of a lot of corrosion to raise the resistance of a big fat pipe to that of a skinny wire. Some people still do pull a CPC through, the main thing it protects against is the situation where a conduit run becomes loose or detached where it enters a box, the fastenings seem to somehow undo themselves over time, mostly from people not doing them up properly in the first place.

Back in the day I seem to remember that using steel as an earth required you to have a resistance Half that of copper. The other point I would make is that we have Many "looped services" where the mains comes in to one house and is then wired in conduit to the next house under the floor. We get them regularly as a "Bad Earth" when some luckless spark tries to do a Ze test on the looped property. Trust me, they do corrode! As I said already I am no longer a spark but are you saying you can use the armor of a SWA cable as an earth now ..... it is steel and I suspect a larger csa than the conductors!

I like that ! The less wire in the terminal the greater the compression and bite ! If 2 single core, there's a risk that only one is trapped under the screw - mechanical testing of each wire after fitting is always a good move. I liked the stacked folds shown in this video - gets everything clamped - just be sure to tighten the screw properly.

@@millomweb technical here: why dont all sockets have the terminals with the flat bit that actually contacts the wires not the screw, they contact across the whole gap

I don't know how they're better. With so little contact surface, I don't know how they manage to handle the current.

@@millomweb I don't know exactly how they work but terminating each wire separately gives a much more reliable connection

JW did a video on Wago connectors.. Take a look, shows you how they works and are constructed.

@@dg2908 From that, you're suggesting a socket should have 9 terminals on the back of it instead of 3 !

@@millomweb well ideally 10 - 1 for the fly lead, but yes. If it was designed from scratch I'm sure it would be possible, and new socket boxes aren't typically less than 35mm anyway

It's an Ideal 45-120-341, can be obtained here: cpc.farnell.com/ideal/45-120-341/metric-wire-stripper-0-75-6-0/dp/TL00610 and many other places.

@@jwflame Thanks

Not recommended, twisting work hardens the copper making it more likely to break, and twisting makes future testing or additions far more difficult. Solder isn't a good idea either, as solder is soft and will flow under the pressure of a screw, causing a loose connection.

Plastic light switches do not have an earth terminal. When mounted to a plastic box, the terminal in the box is used as a place to secure the protective conductor.

The size has to be large enough so that it's not damaged in the event of a fault. Using the same size as the cable is OK - and in most situations that will be 1.5mm² anyway, as larger cables are rarely used for socket outlets. Smaller sizes could be used, but calculation would be required to confirm the size is adequate.

Earth terminals are available separately: www.tradesparky.com/cable-and-management/conduit/steel-accessories/deta-dt40604-earth-terminal-m4-brass drill a 3.3mm hole in the backbox, thread with a M4 tap and screw the terminal in.

If installing the bb put the earth lug at the bottom, it's far easier to see when kneeling!

A good idea, and in many cases essential for fine stranded wires. Of limited value for most fixed wiring, as it's normally only 7 strands and they are of moderate size so unlikely to be missed in most terminals.

I would always use a ferrule if putting a stranded wire into the same terminal as a solid wire. Otherwise the stranded wire can sometimes be incompletely clamped or pull out entirely.

www.screwfix.com/p/screw-cups-8ga-carbon-steel-200-pack/78689

is it just countersunk screw you’ve used then or a pan-head?

is it just countersunk screw you’ve used then or a pan-head?

Standard countersuck woodscrew.

Ideal T-Stripper, part number 45-120-341

@@jwflame Thank you. Hadn't seen these on the big river UK site - until I posted the details you sent. I shall invest in a pair even though I have just bought another cheaper brand which seem OK (though only time will tell how good they are). These being US marketed means they use US wire sizes, but no grief to adapt to/determine the correct UK equivalents (especially for UK T&E and single core mains cable).

Fixing screw could be used, or you can buy brass terminals separately which fit into an M4 threaded hole. Drill a 3.3mm hole and tread to 4mm if there isn't a suitable hole already.

No. The regs do indeed spell this out: 410.3.9 The provision for fault protection may be omitted for the following equipment: (iii) exposed-conductive-parts which, owing to their reduced dimensions (approximate maximum of 50 mm x 50 mm) or their disposition cannot be gripped or come into significant contact with a part of the human body and provided that connection with a protective conductor could only be made with difficulty or would be unreliable. NOTE: This exemption applies, for example, to bolts, rivets, nameplates, cable clips, SCREWS and other fixings.

@@andrewcadby - Again, an industry 'advisory' - catering for cost/time effective solutions. Though I agreed with your explanation, as a matter of extra safety, I always employ a BB CPC tail on metal BB's fixed in walls.

@@Deebz270 that's fair enough, although personally I don't see the point, with the obvious exception of plastic switches etc. The odds of a backbox somehow becoming live without tripping the breaker, let alone the RCD, seem negligible IMO. Also, may I bring to your attention metal consumer unit lids. I have yet to come across one that didn't rely on its fixing screws to earth it.

I hope you meant nod

@@jocramkrispy305 obviously subconsciously john's attention to detail left more of an impression than originally thought, lol

The trouble with twisting is if there is ever a need to separate the wires for modification or troubleshooting the wires have to be un-twisted and it doesn't take many cycles of twisting and untwisting for the wires to break.

Both earth wires must be connected, otherwise sockets elsewhere on that circuit will not have an earth connection.

@@jwflame OK - thanks so much for the reply.

A very very poor path, walls don't conduct worth a damn even when damp, & that's not mentioning walls tend to be sat on an insulating PVC damp proof course even if they did. With a sufficiently sensitive instrument you *might* be able to measure the difference, it'll be swamped by the other variables & other parallel paths in a typical installation though, especially when you consider the boxes get connected to the CPC via the accessory mounting screws as well. Connected via a plated brass screw, or connected via the screw with a parallel conductor to the same very poor path, even with many instances of that one slightly corroded terminal somewhere is likely to make a bigger difference.