Would really like to have a longer interview with the forensic investigator. Would be very interesting to hear what the process is. Also the common faults. There's more than poorly torqued connections but he got cut off...
I think this video helps highlight why isolators between meters and consumer units should be mandatory. That way, the CU tails won't be disturbed when the meter is changed and the meter tails won't be disturbed when the CU is changed. They also add another level of safety in an emergency as well as make life more convenient and safe for electricians.
but you could also argue it is yet another set of connections that could be a point of failure... but i would agree if installed correctly it does make things safer & easier for all involved
They’re essentially free (like 20-40 quid - I see a Wylex 100A jobby on the net for 20.49…)) so they should really be installed whenever the tails are changed by *either* party. And while of course asking that of the metering company is not gonna happen, but it should definitely be part of a CU change with new tails by the customer. Especially if you’re installing a board with a dozen circuits that cost 100 quid each, never mind the other accessories.
@@JasperJanssen I totally agree. An isolator is a tiny cost on a whole new install. It makes everybody's job easier, especially in an emergency. I have usually found Octopus to be good at fitting them FOC during a meter change. Like you said, they're only £20 so no excuse not to fit during a rewire or meter change.
As I've said before, I don't underestimate the importance of torque settings, but at the same time something feels a little bit silly about ensuring the correct torque in the consumer unit while installing your new 50A shower circuit, then proceeding to use your own judgement on the isolator terminals and the connections in the unit itself. 🤔 But then again I also find it silly that we now use metal consumer units in domestic, but it's fine to have the DNO/Suppliers Cutout,Meter, and Isolator all made of plastic, and usually not tightened with a torque screwdriver (I know they don't work to bs7671, but it does just seem a bit daft). And don't get me started on the AFDDs. Well, just because I've got to work to the regs, doesn't mean I have to agree with them. 😂
What I’m also a little skeptical on is the idea that this screw needs exactly 2.0, that 2.2, those 2.5, and that last one 3.5. I think it’s a lot more likely that they each need something in a range.
@@Tomoose1985 yeah. But I suspect that because of it, it wouldn’t be that hard for manufacturers to make sure that a consumer unit has maybe 1 or 2 different torque settings, instead of 6 different ones several of which are super close.
Iv had screws that wobble in the threads on the earth and neutral bar of a certain competitive make. The quality of some of these terminals are moderate in some cases unlike proper brass terminals like in the past made in European countries . Some of the oldest boards including old wooden framed types are still on the wall no burning in decades with no fancy tools.
The old wooden framed boards had 2 screws for each terminal as well as brass terminals you mentioned. Its a pity that manufactures don't incorporate that design into modern boards. You are right about the quality of some of the terminals,all down to cost now it seems.
Shout out to Shahid for standing up for the guys on the coal face. My opinion on torque settings is simple, if the manufacturer say to do it, then JFDI! For the sake of a few minutes, is it really worth the risk not too? Next time your down for your MOT, ask your mechanic if he uses a torque wrench, bet he doesn't winge about it either... Great video as always!!!👍💪
been a mechanic, then a electrician, contractor, Engineer and now a consultant, Its about the fact that there is too Many lawyers qualifying, not enough capacity, so the next gold rush is the trades, when there is a blame, there is a claim, Look how many lawyers firms in the UK are on top of the emissions scandal, I can get how much if I have a VAG motor vehicle?!!! That means being heavily bonded aka top end insurance, qualification inflation, etc, making it a need to have more out goings, before you earn, all this bollocks, while there is so many dodgy people working off the books and making a dogs meal of the job, I have got in touch with the trading standards, etc, yet the same olde people are still about, I guess, problem, reaction, solution, still works, with the banksters, ruling and political class
we have begun to return to steel enclosures, but not to ceramic innards, or dual screw terminations, whilst there are soft plastics involved there is always going to be a risk of melting and ignition
In the old days with the wylex consumer units they had 2 screws on each live and neutral connections. In my opinion it was madness to ever drop this idea and just have 1 screw per connection. This was and is asking for trouble
Main earthing bars for equipotential stuff still do that, like the stuff that makes sure all the metal in your bathroom is at the same voltage. @mike Newman uh… I have never seen a din rail module with two screws on one connection, and it’s definitely not in what’s currently sold.
@@JasperJanssen I sell loads of Wylex units at my wholesalers. All their main switches in the consumer units are twin terminal. Very safe connections and far better than a flimsy plastic cable clamp.
Mike Newman i agree Wylex has twin screws on the incoming main switch. I great idea . The old Wylex pre din rail had 2 screws for each circuit on the live fuse terminal and neutral terminal
Very interesting, but I can’t help thinking that this is nothing more than the manufacturers covering there own ass . As so many sparks have said many times we have done without torque setting and torque screwdriver’s for over a hundred years without any problems, other than some sparks under tightning there connections. The guy from the ECA Clearly said that BS7671 Dose not mention any thing about torque screwdrivers or torque settings, yet Gaz insists. On using the word required. I also felt that that guy Rob was hesitant with his answers . And I have to agree with Darren Plants response,the guy from lewden refused or couldn’t answer the question from the guy from the ECA , the truth is the manufacturers don’t want to accept responsibility if or when there products fail , i do agree to a point that yes we should do everything we can to insure our installations are safe, and if that means we use a torque screwdriver then so be it . And the manufacturers should drop there prices and make them more affordable as well as the breakers. I believe a lot of the problems came about with the introduction of part P and the so-called competent person scams and the short courses. I can honestly say that I am glad I invested in a torque screwdriver a little over a year ago. They are a good tool but not worth the ridiculously high price. But who am I to argue i’am just a humble spark who’s opinion means nothing .Fantastic video Gaz as always 👍👍👍👍❤️
My house was rewired around 30 years ago when using torque screwdrivers wasn't a thing, the only major failure I've had was a loose connection on the DNO fuse a few years ago and I have a LOT of sockets, more than the average house along with a workshop with welders etc. TBH ditch screw connections completely and the largely non existent "problem" goes away completely.
Trouble is they can't really answer, as it's a legal question more than anything. If the manufacturers have done everything reasonable to ensure that faults are sufficiently unlikely, and the installer has put the equipment in to the manufacturer's instructions, who is to blame when a fire occurs? Maybe nobody is to blame, it's just that these things sometimes happen.
Missing the solution to solve this completely in the consumer unit which is push fit terminals that also keep a constant pressure on the cable. Manufacturers need to hurry up and bring them over to the UK.
If you can cause the torqued screw to become loose by a small amount of wiggling the cable then it’s clearly not tight enough. And by the looks of it I doubt it even need the wiggling could’ve just been pulled straight with minimal pressure and it would have given way.
Whenever I use my torque screwdriver it makes the breakers lean over, which looks rubbish and sometimes makes getting the cover on difficult. You can see it in the video clip here too.
If your torque driver makes that happen and your calibrated arm doesn’t, you’re just putting less torque into it. There’s nothing about using a torque screwdriver that puts twist into the units *other* than being fairly highly torqued down.
I agree with you on this. Material quality has gotten progressively worse, starting long before the torque setting requirement. I went through a stage of stripping threads on breakers, to the point where I had to do it in front of the supplier to prove how shit they were.
Hear, hear! This is why manufacturers are putting torque on their products as the quality isn't a patch on what they used to be. As someone as written, they are covering their arses and pushing the problem down the line. But I guess as the installer, you follow the manufacturers instructions and hit a problem do you blame the torque screwdriver manufacturers? Was it + or - 6%, which on 2.5Nm is 2.65 or 2.35. Or was + or - 0.6Nm, which is 3.1Nm or 1.9Nm. Forgive me, as I wasn't too sure what the chap from Wiha actually said.
Well done Gaz this is up there with the video you did regarding testing of RCBOs.One point I would like to say is that for consumer units with rewirable/cartridge fuses you look at the terminals on there and the terminals of today's consumer units.
This video opens an important discussion about, the high amp, long duration, frequent cable movement and risk of accidental tug applied to the EV charging cable. It would be good to see: 1 the regulations written to ensure: safe isolation, long duration load testing, periodic inspection and maintenance at domestic and multi occupancy buildings, 2 equipment manufactured to make certain the method of clamping the conductors ensured a safe and durable installation (spring lever terminal connectors, cable support and glanding built in), 3 the installer can readily achieve installation, testing and future maintenance.
I did not hear it mentioned, but I may have missed it. Everything and everyone has a margin of error. In other words, nobody and nothing is perfect. The point of these standards is to reduce errors thru improving education and practice, as well as and add safeguards if errors or mistakes do occur. For example, we make these connections in an enclosure to add protection if there is a problem with the connection or with the equipment in the enclosure. Manufacturers do their testing and design and recall if problems with those processes result in defects in the field. Additional training and certification helps improve knowledge and skills to prevent future problems. By far the biggest source of problems in my experience is due to ignorance or mistakes during installation - the human factor. Videos like this help to educate and hopefully reduce those most common problems from the professionals. Thank you! But what do we do about the non-professional that causes problems when the professional is absent?
Calibration of these tools and testers needs to come down in price it’s way to expensive and calibration tools themselves are ridiculously expensive as well. That’s an important issue that needs to be addressed.
So what I'm hearing is we need to replace all screw terminals with wago style clamp terminals and / or cable support clamps to minimize moving of the cable at the terminal?
Screw terminals and movement is definitely a bad time. Especially lots of movements, ie vibration. Moving the cable once or twice - like installing or even installing, removing, and reinstalling a socket - is likely to be fine. Continual small movement, like a car engine bay, and things are very unlikely to be fine. Wago style puts constant spring pressure on the wire and it’s much more resistant to that effect.
Interesting. How does the integrity of the connection when torqued to specification depend on the twisted compaction of stranded conductors and whether a ferrule has been used, as opposed to leaving the strands straight and unconstrained? You can imagine the situation where a seven strand wire without twist or ferrule (one central and six surrounding strands) gets clamped in a cage. You could get three stands stacked on top of each other with the rest loose, two pairs stacked with three loose, or all seven strands side by side and clamped or some other combination - all scenarios reaching torque. The more strands in less stacks the more precarious the stability and the greater chance of collapse with movement. That's what happened with your test where you wiggled the wire out. Twisting provides stability by ensuring crossover of strands as does a ferrule even more so but are the torque settings calibrated for this?
Agree, there are too many variables involved in this torque argument. As an engineer and forensic scientist for over 40 years I cannot fully buy into the value of tightening electrical connections to a single torque value and I agree with others that manufacturers are covering there own backsides against over tightening and damaging there poor quality connectors. You only have to compare consumer units from a few decades ago to todays to see the difference in the quality of the connectors!
So, you're telling us that a torque-screwdriver is critical for the consumer unit - but somehow not for the (several dozen) screw connections around the rest of the final circuit ? Come-on guys, you know full well the problem (for years) has been deteriorating manufacturing quality, with CU's made to the cheapest price possible. Let's face it, the CU isn't exactly a selling point for the customer, who'd rather see the money go on shiny decorative accessories, than on a box hidden away under the stairs! Hopefully, the AFDD & SPD requirements will help to redress the balance, as higher quality devices are deemed necessary. If torque was quite as critically important as you say, manufactures woudl be making breakers with proper screws, using TX-star style heads insteead of the sh*te plus/minus heads that require the sparky to lean on the screwdriver to achieve the required torque without cam-out! Specifying the toque lets them get away with cheaper, softer metal on the screws and shifts the burden onto the tradesman ! Yep - proper connections are important; just a shame that manufacturers have avoided their responsibilities for so long !
What final circuit has a dozen screw connections? Why aren’t you just using push in connectors on wagos and modern devices instead of cosplaying that you’re a 1980s electrician?
I build electrical control gear and purchased a torque set to try and avoid these exact problems with contactors, one of the best investments I've ever made.
Unfortunately there was a clear bias going on here, the forensic expert was led all the way and when he did try to talk about factors other than torque causing fires he was closed down!
I've also had an issue in the past where tightening the neutral bar to the required setting snapped it clean in half. Yes it was last thing on a Friday too 😁
There’s an issue which might be overlooked, now most lighting is LED and they have electronic drivers, if the incomer is arcing the lights might not visibly flicker as much as with older lighting, so the early warning is missed.
17:24 - excellent point, I will always endeavor to re-torque connections after installing "Henley" blocks or changing the CU as I would have been moving the tails. However, just how am I supposed to re-torque (or even check that it has been torqued correctly in the first place) the mater-tail connections within the Meter, or indeed the DNO Incomer, if I cannot remove the seal in order to remove the cover and do this, even if I were to re-seal it afterwards...!?
A friend of mine had his resturant burn down & mysterious circumstances, the " electricity board had recently fed a new main into the building. The kitchen was all electric, no gas, so a very high demand. During the night the csu area inc meter & incomer caught fire. Fire brigade sorted it out & dine there investigations & a day or 2 later all the evidence had mysteriously vanished. Insurance company repeatedly tried to blame the people renting it out for the evening with lots of false claims. I can only assume that its far easier to prosecute the tenant rather than the electricity board. All along i said its more than likely loose connections on the newly installed meter/ incomer.
When will we start to see torque settings on the devices connected to these circuits, such as showers? You look in the manuals for these devices and there's no mention of a torque value, just that you should "Make sure all electrical connections are tight to prevent overheating." How tight? I'll get my calibrated arm out?
Well, we’ve got a pretty good idea of the range of torque settings that are necessary on CU gear, so… almost certainly 2.5 to 3 Nm will be pretty good.
Regarding meter tails i Always tighten & give a good wriggle & get another turn & have another wriggle & tighten a bit more. Fairly often i can get meter tails wriggle them & just pull them out.. From the electricity boards side...
Great subject😊 On the subject of sustained loads eg “getting warm ain’t it?” Many of us are getting called to melted or charred sockets which are due to sustained loads “inflated hot tubs”🙄 It’s quite hard explaining to a client the reason why a socket had failed even though in their eyes it’s just a 13amp plug. Drawing a load for a sustained period of time causing this damage I ask how the appliance/device got through testing for public use?? Keep up the brilliant work guys Cheers from tropical Devon 😊😎
Any fully working 13A socket *should* be able to sustain a 10A sustained load, and honestly the margins are such that 13A sustained shouldn’t lead to danger either. Now, if a socket is old and the spring contacts are not so springy any more or the screws not so tight any more (thermal cycling from those high loads can loosen those screws…), you will have a bad time. I’d be willing to bet *most* of the charring happens on sockets that are either old already or just used very frequently.
@@JasperJanssen brand new Hamilton exterior double socket, 16amp A type RCBO, 4 meters of 3core swa, 6 month old green house 2kw heater on a 3 pin plug. (Yes I’ve tested it all) Crispy socket? And now on number 2. Yet this isn’t the first issue me and others have experienced with sustained loads
Good question from Shahid, well done for standing up for the contractor, torque screwdrivers are a good idea, we need to move forward with the times .. would be nice if the manufactures Wiha Wera etc produced a torque test tool, rather than having to send it off, at the moment its easier to just buy a new one off the shelf
Are the forensic investigators able to determine if the terminal that caused the fire was tourqued to the right setting and therefore put blame onto the manufacturer or is it a case of your word against theres? If so what is the answer? Film yourself screwing up every terminal just incase the breaker fails?
I reckon it will come eventually. I've seen torque settings on Nuaire extractor fans and creda digital lot 20 storage heaters manufacturers instructions
All these gimmicks of flimsy cable clamps above the main switch. Loose connections don’t happen at the cable clamp, they happen at the switch terminals themselves. Twin terminal main switch es are a far safer option to protect against loose connections.
They’re better, sure, but afaik they’re just not available in the market. But sure, if you think about it as one screw to make the connection and one to keep that end of the cable from moving even when the cable moves, that’d be a better way to go. Way to go. Hm. Wago!
Who should pay for the torque driver? The electrician on JIB rates or the employer who is liable for any calibrated equipment???? Can’t see many bosses rushing out to buy them. Tightening to a proper level is a skill that is learned. No impact drivers for final tightening ever!!! Though with careful SKILLED use they could be ok for 95% tightening for speed.
The employer, obviously. Who is also going to be the one left holding the bag when you testify that you asked for gear and didn’t get it. (Besides, they’re not even all that expensive… a wera vde set is under 150 euros…)
I love this imaginary subject, and it is so important! if professional electrician has no imagination, there is no way they can understand why and how things work.... Teach your kids to imagine things and They will be great ELECTRICIANS :-0 !!!! ( And not only... )
Would really like to have a longer interview with the forensic investigator. Would be very interesting to hear what the process is. Also the common faults. There's more than poorly torqued connections but he got cut off...
I think this video helps highlight why isolators between meters and consumer units should be mandatory. That way, the CU tails won't be disturbed when the meter is changed and the meter tails won't be disturbed when the CU is changed.
They also add another level of safety in an emergency as well as make life more convenient and safe for electricians.
And yet the DNO would prefer you pay them, less so a 3rd party for the pleasure for fitting a double pole isolator.
but you could also argue it is yet another set of connections that could be a point of failure... but i would agree if installed correctly it does make things safer & easier for all involved
Here, here!
They’re essentially free (like 20-40 quid - I see a Wylex 100A jobby on the net for 20.49…)) so they should really be installed whenever the tails are changed by *either* party. And while of course asking that of the metering company is not gonna happen, but it should definitely be part of a CU change with new tails by the customer.
Especially if you’re installing a board with a dozen circuits that cost 100 quid each, never mind the other accessories.
@@JasperJanssen I totally agree. An isolator is a tiny cost on a whole new install. It makes everybody's job easier, especially in an emergency. I have usually found Octopus to be good at fitting them FOC during a meter change. Like you said, they're only £20 so no excuse not to fit during a rewire or meter change.
As I've said before, I don't underestimate the importance of torque settings, but at the same time something feels a little bit silly about ensuring the correct torque in the consumer unit while installing your new 50A shower circuit, then proceeding to use your own judgement on the isolator terminals and the connections in the unit itself. 🤔
But then again I also find it silly that we now use metal consumer units in domestic, but it's fine to have the DNO/Suppliers Cutout,Meter, and Isolator all made of plastic, and usually not tightened with a torque screwdriver (I know they don't work to bs7671, but it does just seem a bit daft). And don't get me started on the AFDDs.
Well, just because I've got to work to the regs, doesn't mean I have to agree with them. 😂
What I’m also a little skeptical on is the idea that this screw needs exactly 2.0, that 2.2, those 2.5, and that last one 3.5. I think it’s a lot more likely that they each need something in a range.
@@JasperJanssen Yes, and those numbers are in the middle of the range for each terminal size. Say the 2Nm needs 1-3Nm etc...
@@Tomoose1985 yeah. But I suspect that because of it, it wouldn’t be that hard for manufacturers to make sure that a consumer unit has maybe 1 or 2 different torque settings, instead of 6 different ones several of which are super close.
Iv had screws that wobble in the threads on the earth and neutral bar of a certain competitive make. The quality of some of these terminals are moderate in some cases unlike proper brass terminals like in the past made in European countries . Some of the oldest boards including old wooden framed types are still on the wall no burning in decades with no fancy tools.
The old wooden framed boards had 2 screws for each terminal as well as brass terminals you mentioned. Its a pity that manufactures don't incorporate that design into modern boards. You are right about the quality of some of the terminals,all down to cost now it seems.
@@alunstone And the screws were brass, similar expansion to copper. Now they’re plated steel…
@@bigjd2ksome boards in this country have plug in earth rails - basically like a 20-terminal wago plus a couple of larger screw connections.
Shout out to Shahid for standing up for the guys on the coal face. My opinion on torque settings is simple, if the manufacturer say to do it, then JFDI! For the sake of a few minutes, is it really worth the risk not too? Next time your down for your MOT, ask your mechanic if he uses a torque wrench, bet he doesn't winge about it either... Great video as always!!!👍💪
been a mechanic, then a electrician, contractor, Engineer and now a consultant,
Its about the fact that there is too Many lawyers qualifying, not enough capacity, so the next gold rush is the trades, when there is a blame, there is a claim,
Look how many lawyers firms in the UK are on top of the emissions scandal, I can get how much if I have a VAG motor vehicle?!!!
That means being heavily bonded aka top end insurance, qualification inflation, etc, making it a need to have more out goings, before you earn, all this bollocks, while there is so many dodgy people working off the books and making a dogs meal of the job, I have got in touch with the trading standards, etc, yet the same olde people are still about,
I guess, problem, reaction, solution, still works, with the banksters, ruling and political class
we have begun to return to steel enclosures, but not to ceramic innards, or dual screw terminations, whilst there are soft plastics involved there is always going to be a risk of melting and ignition
In the old days with the wylex consumer units they had 2 screws on each live and neutral connections.
In my opinion it was madness to ever drop this idea and just have 1 screw per connection. This was and is asking for trouble
They still do.
Main earthing bars for equipotential stuff still do that, like the stuff that makes sure all the metal in your bathroom is at the same voltage.
@mike Newman uh… I have never seen a din rail module with two screws on one connection, and it’s definitely not in what’s currently sold.
@@JasperJanssen I sell loads of Wylex units at my wholesalers. All their main switches in the consumer units are twin terminal. Very safe connections and far better than a flimsy plastic cable clamp.
Mike Newman i agree Wylex has twin screws on the incoming main switch. I great idea . The old Wylex pre din rail had 2 screws for each circuit on the live fuse terminal and neutral terminal
Very interesting, but I can’t help thinking that this is nothing more than the manufacturers covering there own ass . As so many sparks have said many times we have done without torque setting and torque screwdriver’s for over a hundred years without any problems, other than some sparks under tightning there connections. The guy from the ECA Clearly said that BS7671 Dose not mention any thing about torque screwdrivers or torque settings, yet Gaz insists. On using the word required.
I also felt that that guy Rob was hesitant with his answers . And I have to agree with Darren Plants response,the guy from lewden refused or couldn’t answer the question from the guy from the ECA , the truth is the manufacturers don’t want to accept responsibility if or when there products fail , i do agree to a point that yes we should do everything we can to insure our installations are safe, and if that means we use a torque screwdriver then so be it . And the manufacturers should drop there prices and make them more affordable as well as the breakers. I believe a lot of the problems came about with the introduction of part P and the so-called competent person scams and the short courses. I can honestly say that I am glad I invested in a torque screwdriver a little over a year ago. They are a good tool but not worth the ridiculously high price. But who am I to argue i’am just a humble spark who’s opinion means nothing .Fantastic video Gaz as always 👍👍👍👍❤️
My house was rewired around 30 years ago when using torque screwdrivers wasn't a thing, the only major failure I've had was a loose connection on the DNO fuse a few years ago and I have a LOT of sockets, more than the average house along with a workshop with welders etc. TBH ditch screw connections completely and the largely non existent "problem" goes away completely.
Great question Shaheed. But as usual the manufacturers don’t answer the question. Basically they won’t pay
Trouble is they can't really answer, as it's a legal question more than anything. If the manufacturers have done everything reasonable to ensure that faults are sufficiently unlikely, and the installer has put the equipment in to the manufacturer's instructions, who is to blame when a fire occurs? Maybe nobody is to blame, it's just that these things sometimes happen.
Missing the solution to solve this completely in the consumer unit which is push fit terminals that also keep a constant pressure on the cable. Manufacturers need to hurry up and bring them over to the UK.
Haven’t seen those in European systems either, not on the output side of the MCBs etc anyway?
@@JasperJanssen th-cam.com/video/lcJzr6RWb-4/w-d-xo.html
Now you have
If you can cause the torqued screw to become loose by a small amount of wiggling the cable then it’s clearly not tight enough. And by the looks of it I doubt it even need the wiggling could’ve just been pulled straight with minimal pressure and it would have given way.
Whenever I use my torque screwdriver it makes the breakers lean over, which looks rubbish and sometimes makes getting the cover on difficult. You can see it in the video clip here too.
I tend to hold the breaker by putting gentle pressure to the upper right of its body, that will stop them from leaning.
If your torque driver makes that happen and your calibrated arm doesn’t, you’re just putting less torque into it. There’s nothing about using a torque screwdriver that puts twist into the units *other* than being fairly highly torqued down.
Better quality fittings are much needed, look at the quality of terminals on much older equipment
I agree with you on this. Material quality has gotten progressively worse, starting long before the torque setting requirement. I went through a stage of stripping threads on breakers, to the point where I had to do it in front of the supplier to prove how shit they were.
Hear, hear! This is why manufacturers are putting torque on their products as the quality isn't a patch on what they used to be. As someone as written, they are covering their arses and pushing the problem down the line. But I guess as the installer, you follow the manufacturers instructions and hit a problem do you blame the torque screwdriver manufacturers? Was it + or - 6%, which on 2.5Nm is 2.65 or 2.35. Or was + or - 0.6Nm, which is 3.1Nm or 1.9Nm. Forgive me, as I wasn't too sure what the chap from Wiha actually said.
Well done Gaz this is up there with the video you did regarding testing of RCBOs.One point I would like to say is that for consumer units with rewirable/cartridge fuses you look at the terminals on there and the terminals of today's consumer units.
This video opens an important discussion about, the high amp, long duration, frequent cable movement and risk of accidental tug applied to the EV charging cable. It would be good to see: 1 the regulations written to ensure: safe isolation, long duration load testing, periodic inspection and maintenance at domestic and multi occupancy buildings, 2 equipment manufactured to make certain the method of clamping the conductors ensured a safe and durable installation (spring lever terminal connectors, cable support and glanding built in), 3 the installer can readily achieve installation, testing and future maintenance.
I did not hear it mentioned, but I may have missed it. Everything and everyone has a margin of error. In other words, nobody and nothing is perfect. The point of these standards is to reduce errors thru improving education and practice, as well as and add safeguards if errors or mistakes do occur. For example, we make these connections in an enclosure to add protection if there is a problem with the connection or with the equipment in the enclosure. Manufacturers do their testing and design and recall if problems with those processes result in defects in the field. Additional training and certification helps improve knowledge and skills to prevent future problems.
By far the biggest source of problems in my experience is due to ignorance or mistakes during installation - the human factor. Videos like this help to educate and hopefully reduce those most common problems from the professionals. Thank you! But what do we do about the non-professional that causes problems when the professional is absent?
Calibration of these tools and testers needs to come down in price it’s way to expensive and calibration tools themselves are ridiculously expensive as well. That’s an important issue that needs to be addressed.
I think the spec on the Wiha torque driver is +/-6% not +/-0.6Nm. So e.g. 5Nm +/-0.3Nm, or better. 🙂
Question for all sparks . Where do you see bad connections at consumer units ?? On neutral bars or breakers ??
Round terminals on the main switch instead of square boxes, cables aren't square.
So what I'm hearing is we need to replace all screw terminals with wago style clamp terminals and / or cable support clamps to minimize moving of the cable at the terminal?
Screw terminals and movement is definitely a bad time. Especially lots of movements, ie vibration. Moving the cable once or twice - like installing or even installing, removing, and reinstalling a socket - is likely to be fine. Continual small movement, like a car engine bay, and things are very unlikely to be fine.
Wago style puts constant spring pressure on the wire and it’s much more resistant to that effect.
Big thumbs up for who made that wall art in the beginning of this video ! I watched the video till the end !
Interesting. How does the integrity of the connection when torqued to specification depend on the twisted compaction of stranded conductors and whether a ferrule has been used, as opposed to leaving the strands straight and unconstrained?
You can imagine the situation where a seven strand wire without twist or ferrule (one central and six surrounding strands) gets clamped in a cage. You could get three stands stacked on top of each other with the rest loose, two pairs stacked with three loose, or all seven strands side by side and clamped or some other combination - all scenarios reaching torque. The more strands in less stacks the more precarious the stability and the greater chance of collapse with movement. That's what happened with your test where you wiggled the wire out. Twisting provides stability by ensuring crossover of strands as does a ferrule even more so but are the torque settings calibrated for this?
Agree, there are too many variables involved in this torque argument. As an engineer and forensic scientist for over 40 years I cannot fully buy into the value of tightening electrical connections to a single torque value and I agree with others that manufacturers are covering there own backsides against over tightening and damaging there poor quality connectors. You only have to compare consumer units from a few decades ago to todays to see the difference in the quality of the connectors!
So, you're telling us that a torque-screwdriver is critical for the consumer unit - but somehow not for the (several dozen) screw connections around the rest of the final circuit ? Come-on guys, you know full well the problem (for years) has been deteriorating manufacturing quality, with CU's made to the cheapest price possible. Let's face it, the CU isn't exactly a selling point for the customer, who'd rather see the money go on shiny decorative accessories, than on a box hidden away under the stairs! Hopefully, the AFDD & SPD requirements will help to redress the balance, as higher quality devices are deemed necessary. If torque was quite as critically important as you say, manufactures woudl be making breakers with proper screws, using TX-star style heads insteead of the sh*te plus/minus heads that require the sparky to lean on the screwdriver to achieve the required torque without cam-out! Specifying the toque lets them get away with cheaper, softer metal on the screws and shifts the burden onto the tradesman ! Yep - proper connections are important; just a shame that manufacturers have avoided their responsibilities for so long !
What final circuit has a dozen screw connections? Why aren’t you just using push in connectors on wagos and modern devices instead of cosplaying that you’re a 1980s electrician?
And ferrule your stranded conductors chaps or you may aswell throw your torque screwdriver in the bin!
100% this . More Importantly .The whole "schemes" set up in the UK is a FARCE
I build electrical control gear and purchased a torque set to try and avoid these exact problems with contactors, one of the best investments I've ever made.
I'd love to listed to an hour of the electrical forensic investigator
More content from Rob on the way soon
Unfortunately there was a clear bias going on here, the forensic expert was led all the way and when he did try to talk about factors other than torque causing fires he was closed down!
I've also had an issue in the past where tightening the neutral bar to the required setting snapped it clean in half. Yes it was last thing on a Friday too 😁
There’s an issue which might be overlooked, now most lighting is LED and they have electronic drivers, if the incomer is arcing the lights might not visibly flicker as much as with older lighting, so the early warning is missed.
17:24 - excellent point, I will always endeavor to re-torque connections after installing "Henley" blocks or changing the CU as I would have been moving the tails. However, just how am I supposed to re-torque (or even check that it has been torqued correctly in the first place) the mater-tail connections within the Meter, or indeed the DNO Incomer, if I cannot remove the seal in order to remove the cover and do this, even if I were to re-seal it afterwards...!?
A friend of mine had his resturant burn down & mysterious circumstances, the " electricity board had recently fed a new main into the building. The kitchen was all electric, no gas, so a very high demand.
During the night the csu area inc meter & incomer caught fire. Fire brigade sorted it out & dine there investigations & a day or 2 later all the evidence had mysteriously vanished. Insurance company repeatedly tried to blame the people renting it out for the evening with lots of false claims.
I can only assume that its far easier to prosecute the tenant rather than the electricity board.
All along i said its more than likely loose connections on the newly installed meter/ incomer.
When will we start to see torque settings on the devices connected to these circuits, such as showers? You look in the manuals for these devices and there's no mention of a torque value, just that you should "Make sure all electrical connections are tight to prevent overheating." How tight? I'll get my calibrated arm out?
Well, we’ve got a pretty good idea of the range of torque settings that are necessary on CU gear, so… almost certainly 2.5 to 3 Nm will be pretty good.
Regarding meter tails i Always tighten & give a good wriggle & get another turn & have another wriggle & tighten a bit more. Fairly often i can get meter tails wriggle them & just pull them out.. From the electricity boards side...
I have been out to a mess like that. The CU was fitted by Scottish Power so I was told.
Great subject😊
On the subject of sustained loads eg “getting warm ain’t it?”
Many of us are getting called to melted or charred sockets which are due to sustained loads “inflated hot tubs”🙄
It’s quite hard explaining to a client the reason why a socket had failed even though in their eyes it’s just a 13amp plug.
Drawing a load for a sustained period of time causing this damage I ask how the appliance/device got through testing for public use??
Keep up the brilliant work guys
Cheers from tropical Devon 😊😎
Any fully working 13A socket *should* be able to sustain a 10A sustained load, and honestly the margins are such that 13A sustained shouldn’t lead to danger either.
Now, if a socket is old and the spring contacts are not so springy any more or the screws not so tight any more (thermal cycling from those high loads can loosen those screws…), you will have a bad time. I’d be willing to bet *most* of the charring happens on sockets that are either old already or just used very frequently.
@@JasperJanssen brand new Hamilton exterior double socket, 16amp A type RCBO, 4 meters of 3core swa, 6 month old green house 2kw heater on a 3 pin plug. (Yes I’ve tested it all)
Crispy socket? And now on number 2.
Yet this isn’t the first issue me and others have experienced with sustained loads
Gaz, What is Rob’s surname? His input is hugely useful 👍
Dr Robert Weller - Electrical investigations LTD
Good question from Shahid, well done for standing up for the contractor, torque screwdrivers are a good idea, we need to move forward with the times .. would be nice if the manufactures Wiha Wera etc produced a torque test tool, rather than having to send it off, at the moment its easier to just buy a new one off the shelf
And a torque test tool tester.
Wiha do produce a torque test screw tool difficult to get hold of though.
interesting to know, never seen one advertised, handy to have alongside a calcard.. cheers guys
@@thattoolguy9432 here it is
th-cam.com/video/r9P05BFgAuQ/w-d-xo.html
Are the forensic investigators able to determine if the terminal that caused the fire was tourqued to the right setting and therefore put blame onto the manufacturer or is it a case of your word against theres? If so what is the answer? Film yourself screwing up every terminal just incase the breaker fails?
Yes they have methods to identify poor connections after the event.
I wonder how much torque a person can have in his hand or arm (average)?
and how would one become a forensic investigator 🕵️♀️
So we’ve torqued all my connections in the consumer unit. I never see torque values for sockets, switches, cooker switches, shower switches.
I reckon it will come eventually.
I've seen torque settings on Nuaire extractor fans and creda digital lot 20 storage heaters manufacturers instructions
I've seen tight and stupid tight .
We used to tighten terminals until you wrist clicked, now it's a torque screwdriver that clicks. Understanding moves on so should we 😎🤡🐔
All these gimmicks of flimsy cable clamps above the main switch. Loose connections don’t happen at the cable clamp, they happen at the switch terminals themselves. Twin terminal main switch es are a far safer option to protect against loose connections.
They’re better, sure, but afaik they’re just not available in the market. But sure, if you think about it as one screw to make the connection and one to keep that end of the cable from moving even when the cable moves, that’d be a better way to go.
Way to go. Hm. Wago!
Who should pay for the torque driver? The electrician on JIB rates or the employer who is liable for any calibrated equipment????
Can’t see many bosses rushing out to buy them.
Tightening to a proper level is a skill that is learned. No impact drivers for final tightening ever!!! Though with careful SKILLED use they could be ok for 95% tightening for speed.
The employer, obviously. Who is also going to be the one left holding the bag when you testify that you asked for gear and didn’t get it.
(Besides, they’re not even all that expensive… a wera vde set is under 150 euros…)
I love this imaginary subject, and it is so important! if professional electrician has no imagination, there is no way they can understand why and how things work.... Teach your kids to imagine things and They will be great ELECTRICIANS :-0 !!!! ( And not only... )
Looks like I have been blocked or my comments have been hidden? . But who am I to argue i’am just a humble spark who’s opinion means nothing.
We don’t block or hide comments.
@@efixx yes I know . It’s bloody you tube playing silly buggers again, just as Facebook do sometimes.or is apple?
Too controversial ridiculous topic!
What about attaching the Wiha torque thingy onto the end of an impact driver?
It’s a little too expensive for that. You’ll destroy it quite rapidly.
hello sir i also do the same work and i want to do better work by staying with you and i am from india and i need job