TORQUE SETTINGS: DO ELECTRICIANS HAVE CALIBRATED ARMS?

[@efixx]

LEARN MORE ABOUT ELECTRICAL CONNECTIONS AND TORQUE: Approved CPD training module in association with Wiha ⚡️🚧👉 www.efixx.co.uk/Know%20How/Torque-setting-of-electrical-connections

[@robe1937]

Having worked as a senior aircraft maintenance technician I would love to know how you tested the torque on a fixing retrospectively. If you use some form of dial torque clockwise you’ll have to above the original torque before the fixing moves and you’ll have to see the precise moment the fixing moves. If you use a dial torque anticlockwise then your not measuring the same torque. The only accurate way to measure torque is during application. If the fixing have been over tightened then you could have a higher run down torque, which then impacts the clamping force. I do admire the effort.

[@apart-timeastronaut6530]

I stopped watching the video once I read this since I was already making the same conclusions

[@efixx]

Great input thanks - we did indeed use a torque meter and watch for the point the fixing moved clockwise. The torque screwdrivers used by electricians are typically +/- 6%.

[@steve11211]

Surely though even i you plus or minus a bit of torque the point is still the same, through a range of electricians from experienced to not so experienced unless you use a toque screwdriver then you will be all over the place, i believe on another video they used a torque screwdriver and then used the measuring device and the measuring device actually showed that the screws were torqued to roughly the correct value so they have a benchmark to compare against. Not disagreeing with your observations but just adding something that they didnt actually tell you.

[@robe1937]

@@steve11211 thank you. It’s just that your looking or feeling for probably one degree of movement at a radius of 20mm and that’s really difficult.

[@x65535x]

@@efixx I think he said that in a bit of a confusing way. After a fastener is torqued tight it will take more torque to get it moving again that was originally applied. By measuring how much torque it takes to start rotating the fastener again you will always measure higher than the applied torque. The best bet would be to torque each fastener down with a calibrated tool then measure the torque to start rotating the fastener which will be higher. Use that ratio as a scale factor for measuring the contestants torques.

[@waynio67]

Everyone knows it’s two dugga dugga’s for mcb’s and three dugga dugga’s for isolators 😂😂

[@efixx]

More Dugga coming soon

[@pn8902]

@@efixx can you also show how much the copper for different conductors should deform when being torqued up and compare how much the impact driver deforms the conductors so we can see the difference, also a good way to know if your impact is actually doing it harder than you think

[@robertburrows6612]

The regs state quite clearly you install and electrical accessories according to the manufacturer instructions, that includes the CU. If there's a torque setting then you tighten to that setting. If things finish up in court the book of regs will be quoted at you and you will be required to produce you torque screwdriver , if you can't the prosecution will have a field day with you and the chances are you will loose

[@JohnSmith-kb5ku]

“Loose”. I like it.

[@torbjrnfjeld1799]

As a curious observation, I have a Wera torque screwdriver with a range from 1.2 to 3.0Nm. If I torque up an MCB to 1.2Nm and then dial it up to 3.0Nm, the difference on the screw itself between the two extremes is something like 1/8 of a turn. 1/8 (!) of a turn… As the screw tightens, the torque increases at an insane rate and I struggle to accept that getting 1.8Nm vs 2.5Nm actually has any effect other than satisfying some arbitrary setting requirement made up by a pencil-pusher… I doubt there’s actually a difference when it comes to safety and/or function. It’s a consumer unit… not a space shuttle. But with that said, you can’t say you followed the manufacturers instructions to the letter if you don’t use one, and fighting that is probably futile. Wouldn’t surprise me if there’s suddenly a requirement to use laser levels (calibrated within the last 12 months) for installations too, and not regular bubble levels. Another "you have to buy this expensive tool now to stay legal" exercise…

[@markrainford1219]

What a great idea. We all know that electrons roll out of wonky DBs.

[@Mtaalas]

Torque is almost directly related to the resistance of the connection. And you also need enough torque to deform the copper wire (and it's specified for the LARGEST diameter that fits the terminal) and that deformation does multiple things: makes the connection area larger, thus decreasing the resistance and it also creates air tight area that doesn't corrode easily. Also, when you deform the wire, you make absolutely sure it cannot be yanked out because it's an interference fit and there needs to be more movement for longer for it to work itself loose. 2.5Nm seems excessive, until you put the largest diameter of wire allowed into the terminal (or even TWO of the largest that fit) and notice that you're barely tickling it with anything less and that it doesn't deform enough to be secure for decades. Million heat cycles, might be ran at high current today and nothing tomorrow, could be -30degreed on winter, +40 during summer... you don't know. It moves around, works itself loose and sooner or later it's not secure anymore... Unless you tighten it to the spec.

[@FirstDan2000]

Great intro. That comparison to an aeroplane is the perfect comparison. I laughed my head off whilst you were describing it.

[@reftech1]

How much torque a screw can stand before it strips, depends on the material, the thread pitch, diameter etc. Torque screwdrivers ensure that you do not stress the threads too much, to the point that it strips. Proper torque alone does not ensure a good connection. You can torque it right but if the wire stripping is not done properly and you insert the wire improperly, trouble will arise. Using a wire ferrule for stranded wire is recommended. Using a torque screwdriver can give you piece of mind. My main issue is the price. I would like to use one but I cannot afford it yet.

[@tonygray7751]

perhaps you should inform people that when they have finished using a Toque screwdriver that it should be reset to the Zero settng, if they leave it at a set point it can have adverse effects on the tool

[@efixx]

We think this depends upon the brand of driver - but will check

[@tommymack3210]

That is the case for most torque screwdrivers

[@lemech]

I heard you don’t need to do that if the torque screwdriver is digital type.

[@Sparks1Plumbers0]

Have always done this with every manually adjuster torque driver.. be it a wrench or a screwdriver I've ever used. TBH it's just Good Practice 🤔

[@Mtaalas]

You have to calibrate torque tools time to time anyway. But yes, you're correct.

[@three-phase562]

I think the torque screwdrivers do a good job. I went through a transformer control panel a while back and found around 60% of the connections were considerably loose in comparison to the recommended tightness from the manufacturers.

[@brianmac001]

It would help if they didn't charge the silly money for the screwdriver! I could buy a decent, large torque wrench for working on my car for a lot less money than they charge for the screwdrivers.

[@Buzzer]

Seen many use an impact to torque, being told under torque is a terrible fire hazard but over torque isn't something to worry about. He does also go over all the terminals again to ensure it is still torqued.

[@mattylad8035]

Something you could do for a video is the effect of overtightening on wires, wires that have bootlace crimps on and the different type of terminal and how and why that affects the torque level. That would be interesting to see

[@christastic100]

We all know that the recommended torque settings will not work for some cables such as stiff tails and larger cables unless they are wiggled around to rearrange the strands in those terrible steel cage square terminals .The round brass terminals were little problem but these modern terminals exaggerated the problem by the manufacturers creating cheap nasty squeaking terminals . Also that screwdriver has a too narrow handle by far .

[@efixx]

Stay tuned for more on this topic.

[@Mtaalas]

you should use end ferrules with stranded wires...

[@bimble7240]

It would be interesting to know how many of the participants had already been using torque screwdrivers, as this would have given them some idea of what say 1.5 or 5Nm feels like.

[@waynio67]

Had mine for a few years now, I’m mostly domestic ( yeah a house basher 😂) but I use it all the time when changing CU’s, just have to remember to set to zero when not in use

[@David-dz8jb]

Does the torque setting change over time I wonder? In my experience screw terminals can loosen with age and use. How often have you taken taken a socket off the wall to check it out only to find the terminals are not very tight and in some cases the wires just pull out of the terminal. The simple act of plugging a appliance into a socket can over time loosen the terminals. As copper is pretty soft I imagine it will yield under the stress of compression. Perhaps the torque setting is only correct at the initial install and degrades over a time……..just a thought

[@Mtaalas]

Once every 5 years is a good idea... hire someone to go through all of them. Can't take more than an hour so 100€ tops... cheap insurance.

[@Mtaalas]

I've never seen torque wrench used on consumer equipment. But go to factories and transfer network stuff... that's basically a required tool. And someone WILL check your work and if it's off, you get an earful since it's huge liability.

[@njwareing6408]

Great video, always love your content

[@SmithyScotland]

Would love to know how the manufacturers can up with their specified numbers. Picked out the air? Why 2.5 rather than 2.4 or 2.6?

[@torbjrnfjeld1799]

I suspect Wylex went "so if Hager used 2.3Nm, then ours will be 2.4Nm", then BG went "screw that, it’s 2.5Nm" before Schneider said "nobody’s taken 1.8Nm yet? We’ll have it" and so on…

[@alancooper7018]

Perhaps the question should be asked ‘are the manufacturers torque settings too stringent’! Let’s face it tightening too loosely causes bad or poor connection possibly leading to wires coming out, heating effects etc; over tightening may cause damage to screws, cable, equipment or cause future maintenance problems. but in between these extremes their will be a wide range of suitable and safe tightnesses. An experienced engineer/electrician should be able to easily tighten within this range.

[@tonymartin3780]

Cracking video lads , 👍😀 hopefully people use torque tools now and not rely on experience “I’ve don’t it for years “ comment 😀

[@jonp6798]

Where are Gary and Gordon’s results? Put your arms on the line!

[@efixx]

Good idea we’ll do that in our next live stream

[@windward2818]

If you go much above 25 inch-pounds (2.8 N-m) using a screw driver the operator will need above average hand and wrist strength. Fortunately, you can move up to a 1/4 inch drive torque wrench and use a screw driver to it. I find the small 1/4 inch drive wrench is much easier to use and usually quicker than a normal torque screw driver that does not ratchet.

[@billsbasementworkshop1902]

Hi, Thanks for another informative video. A while ago I asked if you knew why WAGO don't make 4 way blocks. Did you find out why? Also for novices like me, could you please do a vid on how to fit a SPD? Thanks.

[@waynio67]

They do 6 way ones

[@efixx]

We are working with Wago on some new content - thanks for the memory jogger I'll put it on the question list.

[@robintodd3901]

The good sparks do… Torque screwdriver yet good idea is if you ask me for the sparks who can’t tighten connections correctly which to me is part of the job to understand how tight something should be compared to another connection.

[@davideyres955]

When we get older we tighten until you hear the click. The click in question from yer bones. 🤪🤪🤪

[@efixx]

Very true 😂

[@MulticoElectrical]

That’s really surprising. I thought most of them would it get it pretty bang on. I’ve just given in and order a Draper set for me and the apprentice. 🤙

[@pn8902]

I think if electricians had access to a tool that reads out the torque they are applying to the screwdriver then that would help "train" the arm. I dont even know what 1Nm feels like so how would I be able to guess 5Nm...shouldn't be guessing anyway, use the right tools! :P

[@steve11211]

If you have a torque screwdriver and are doing up the screws, I tell you what though its amazing how much 2.5nm actually is, if you do an entire consumer unit I always have to stop at least a few times and by the end my arm is knackered..

[@patmcnally6]

I am sorry to say Nobody has a Torque set arm. I always use a Torque screwdriver to check. But I would not use a Power Drill without a Calibrated Chuck one on Maketa etc Battery Drills Still can Distroy Terminals.

[@efixx]

Tune in to the next part of the series when we show what happens if you use an impact driver

[@patmcnally6]

@@efixx I Definitely will

[@johndufton9686]

For many years electricians have been wiring up Consumer Units etc without any torque screwdrivers. I don't own one and I do everything by feel.

[@dansheppard2965]

Why are there so many different torque settings? It seems needlessly complex. Could they not be standardised to at least a few sensible fixed points within a wide range and then construction of terminals just be to a standard as everything else in a well-managed industry?

[@Mtaalas]

depends on the terminal size, screw thread pitch, contact area etc. There's no one that'll fit everything....

[@petetong3166]

Your mock questions would be amazing if the right answers were also on their so I can find out right answer

[@efixx]

what answer are you looking for?

[@craigemmott4976]

I see one problem, the isolator, if I remember correctly, was 0.8nm and all electricians torque screwdrivers start at 1nm that I've seen.

[@sergiofernandez3725]

Surely that will require another specialist tool which get low usage and will in time need to be calibrated. Do some of the manufacturers of the CU and associated internal kit have shares in a tool company that make the torque drivers. In the Early 1990's Apple computers started to mandate that exotic tools were used to tighten up screws in their machines. For most people they thought this was to combat badly trained technicians, which indeed it was. Years later people learned that Apple had bought shares in some of the companies that made the exotic tools.

[@efixx]

Depends upon the brand - the Wiha one we use goes from 0.8Nm to 5.0Nm.

[@craigemmott4976]

@@efixx I'm glad to be corrected. Having delved a little bit deeper, I can see one Wiha model which starts at 0.8nm. When you just do general Google search, most brands start at 1nm.

[@hasankhan-ey5oz]

Good job i like your videos

[@efixx]

Thanks

[@merlin5476]

I always prefer to use my own Torque & wits. I always give 25mm tails a good tightening then always wriggle them afterwards quite abit & always get another full turn on the terminals. Countless times i have seen an old( & new) installation with loose tails. I have also found screws behind plate switches that have come out completely!!!! How does that occur 😮!!

[@jonathanrose456]

You take legal responsibility for electrical equipment if you don’t install it to the manufacturers specifications, so unless you want that responsibility… use a torque driver

[@JohnSmith-kb5ku]

I do hope you are stripping the cables back to the correct length too, that is the case. Make sure you measure the correct length when you strip.

[@jonathanrose456]

@@JohnSmith-kb5ku that’s what my precistrips are for. Also means you don’t nick the copper, which we all do from time to time. Insurance companies are looking for ANY reason not to pay out in the event of an accident or fire, etc., & spending a few quid on tools to avoid losing my house (which will happen if I’m found to be negligent), that also make my job easier, is a no brainier. Having job sheets with tick boxes also avoids sleepless nights worrying but, few sparks employ that methodology either.

[@seandempsey7351]

I have said my peace on this . So I won’t say a word, simply can’t be bothered I just get ignored and my opinion isn’t welcome anyway . Unless It’s a positive one . I will say this though please stop with the required, it is not a requirement legal or otherwise to use a torque screwdriver it is only a recommendation. But yes it’s better to use one then not to

[@steve11211]

BS7671 is not a legal requirement either what BS7671 does do is cover your bum if anything goes wrong and is a standard that should be worked to so that we all work to the same level.. You could wire line as green and yellow, neutral as brown and cpc as blue, electricity doesnt care (Assuming not using T+E) and it will still all work, you know what you did, whats the problem.

[@line10cls]

I have just had a smart meter fitted. thw torque setting was when the screw terminals squeeked it was tight enough/

[@spankeyspangler]

Free fire extinguishers with every ccu. 😂😂

[@cag9284]

Calibrated arm...I bet their the same electricians who use a impact driver as a drill. 😂😂

[@gideonlapidus8996]

I just know the power of my screwdriver, from experience

[@peterpanci78]

I never use a tourqe screwdriver. I always tide them up tide

[@johnheath86]

This video did not age well with the Boeing comments at the beginning 😂😂

[@bernardcharlesworth9860]

Yea

[@rudkin69]

Wouldn't trust the bloke with the vacuum, definitely not a spark 😂

[@bernardcharlesworth9860]

Yes

[@shausen1179]

Yes.

[@kevinklingan8249]

Hell no, as a hvac tech I am certain that electricans are the least skilled tradesmen when regards to electrical fingerspitzengefuhl.

[@Sparks1Plumbers0]

So.... how the hell have we survived for the past 140 years without every connection Not being torqued up? Oh, and don't forget screw terminals on things like sockets, light fixtures etc which are still without a torque value on them horrid little screws! Just saying 🤔

[@HunGredy]

I can't speak for Western Europe but in the East we consistently see lamps burn out and switches malfunction due to sparking and loose cables. Many of the houses here still have centuries-old aluminium wires embedded directly in the wall, some still haven't upgraded to new breaker types. I'm not saying houses will burn down, but definitely there is a risk of invisible danger and inconvenience.

[@stevenwalker8372]

A spark with a hoover 🙈

[@efixx]

shhhh

[@AlexMelnikovV]

pity there is no translator

[@efixx]

what do you want translated?

[@ELECTRICLIFE4U]

👍👍👍👍👍

[@Dog-whisperer7494]

Oh come on, a bowing 737 is a big difference compared to a CU . If you’re going to do a comparison then please keep it real. A consumer unit will never ever be subjected to the vibration and stresses a 737 would be subjected to. Or any other aircraft for that matter. 😂

[@acespark1]

I have a calibrated tongue and it talks the talk 😛🤡🐔

[@paul_my_plumbs_uk]

My screws will be loose after a few on board 🍺🍺🍺🍺