10 Mistakes EVERYONE Makes When Doing DIY Electrics!💥
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- Опубликовано: 9 май 2024
- DIY Electrics can be DEADLY - so in this video we reveal 10 things that lots of DIY'ers do with electrics that are SUPER DANGEROUS. If you're a DIYer and you're ever in doubt about how to do some electrical work in a safe way, just call a qualified electrician! What's the worst DIY mistake you've ever come across?
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⏱️Timestamps
00:00 - Introduction
00:23 - DIY mistake 1 - A big NO
01:50 - DIY mistake 2 - Classic mistake
02:22 - DIY mistake 3 - This is a problem
04:17 - DIY mistake 4 - Be careful with this one
05:52 - DIY mistake 5 - Get the correct cable for the job
06:10 - DIY mistake 6 - Don’t make such a MESS!
06:40 - DIY mistake 7 - BIG risks
07:20 - DIY mistake 8 - Very common mistake
08:22 - DIY mistake 9 - Stripping back the wire way too far
09:37 - DIY mistake 10 - This could lead to a FIRE
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This video is for entertainment purposes only please do not attempt to copy or recreate it. Do so at your own risk.
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If you want to make sure you are doing your job correctly, then you will need a proper test device for that. ⚡Kewtech KT 1780 - amzn.to/43Gglzk
Should also include a link for a proving unit.
It's rather KT63DL
Laughing at soldering??? Are you honestly suggesting the way all electronics is made is wrong ?
i was putting some lights up in friends bathroom and the replacement lights had multi stranded cables i put it into the connect and screwed it up pulled and it come out the connector so i though thats not safe, i had a crimping set i brought from lidle and i put like a small tube round the multiple strands crimped that onto there, did twisty 90* bendy thing it didnt come off so i put it into the connector block thingy and screwed it in made sure it didnt come out off that and then put the light to the ceiling, so i think i mad a fairly reasonable effort to make it safe. my general rule of thumb is pull on it and make it look pretty, if it dont brake with a pull and it looks need then its more than likely safe
Prefer the Fluke 150 myself.
Makes me want to do a video about the mistakes I've discovered done by qualified electricians on houses I have purchased over the years!
what proof do you have(visual?)that they were done by qualified electrician?
@@waynethomas3638 e.g. New build house with contract for whole estate done by very large contractor. Etc.
Over-tightening terminals on copper wire is a favourite. Fine for a few years but the excessively squashed conductors can fail and create points of high resistance
EDIT: lol just got to the bit where this was mentioned as a DIY mistake but the pros do it all the time 😅
As with any profession there are good ones and bad ones.
Please share what you have come across, it may save someone’s life.
Fun stuff and so typical mistakes for many DIYers.
But the wound up extention cord running hot, has nothing to do with inductance. It simply the resistance of the cable that cause it to heat up - but being rolled up like a coil, the heat can not escape from the cable very easy (compared to if the cable is rolled out), so the temperature rise quite a lot
As the resistance of copper also goes up by the temperature, this causes it heat up even more in a sort of thermal runaway. This can cause the coil of cable to get toasty, very quickly.
Could not give you two thumbs up.
three thumbs up, the out and return are parallel, so loop area is negligible in this instance , so inductance is negligible, surprised at Jordan for getting that wrong.
Right, and I would like to add that, even if there were a significant inductance (which is not there because the magnetic fields due to the two opposite currents cancel almost perfectly) it would not lead to any power dissipation, only to a lossless voltage drop. It is only the resistive part of the impedance that leads to power dissipation and Joule heating. I do not know why this incorrect belief about the hypothetical inductance and even more hypothetical associated power dissipation of coiled cables consisting of two conductors with opposite currents is so common: I heard it for the first time in high school when I was working part time for a local tv station: a technician from.a local tv production company told me that power cords for halogen lights should not be wound in operation motivating the recommendation with the incorrect inductance argument.
waiting for his reply on this.. haha. ironic how the video is specifically about making mistakes.. lol
Thanks for the clarification! That does make sense 👍
The heat produced in a wound up extension lead is NOT caused by induction. It is caused by conductor resistance and lack of cooling.
Exactly!
Bifilar coils like this cancel out the magnetic field nearly completely.
Not knowing about reduction Factor on stacked cables and it's danger is a typical DIY mistake.
Sometimes making fun of others can backfire.
To expand on these accurate comments by op & @AzrethK9. Yes the coil is definitely Bifilar and therefore a non-inductive coil for this purpose (basically the magnetic field of the neutral cancels out the live, why you can't use clamp meters on power cords). Additionally self-induction is not a method of energy dissipation, it is a form of energy storage. If the coil was inductive the energy world be stored in the magnetic field and released later in the AC cycle. This why PFC devices are called for on inductive loads, they don't affect your real power consumption, just the power factor.
What this is, is an example of a hazard caused by bundling many (slightly resistive) conductors together and there being nowhere for the heat to go. Think of it like wrapping the inner wire in a blanket, and an electric blanket at that. This same hazard would occur if there were many separate cables all carrying this current, this is a hazard electricians should understand.
I think this myth may come from two places, people knowing a coil can be inductive, assuming it is because they don't know what an inductor is; and then assuming that one thing they now see is the cause, ignoring the obvious real cause they should already know about.
The other possibility is people are thinking about induction hobs, which is a whole different situation, firstly they use an inductive coil and secondary (pun intended) there is a pan to act as the other, shorted, winding.
One cat we had used this to good effect - it would curl itself up and go to sleep on a coiled extension lead feeding a heater.
Exactly. Even if it wouldn't be bifilar, the number of winds and the low frequency would lead to no real inductive effect.
Extension leads - Inductance is not the problem, it's the resistance that creates heat. Cable is rated for a situation where air can circulate around it. Winding it onto a reel adds insultation so the copper temperature rises.
One other thing not mentioned, but something I've not seen done in a fair number of outdoor DIY cabling setups are Drip Loops. Instead you tend to see cables running straight down a wall, right into a junction box with nowhere for the water to go!
I've seen the same done by professional CCTV installers recently. Cameras had gone out. I checked the weatherproof enclosure, unscrewed the cover and about a litre of water poured out. All cables were top-entry, no drain hole, system had worked until water got up to the level of the power supply for the network switch.
Also not-so-professional cable contractors (I won't name names but let's just call them the S*** Wiring Guys) running Ethernet feeds into the tops of Wiska 308s or through drilled-out holes in the rear. As they fail the cables just get jelly-crimped now as if the jack is replaced it just rots again.
Another vital step for #7: Check your circuit testing device for proper operation before you rely on it....
Yep, it doesn't really have to be a very expensive device either, but testing that it shows a circuit before turning off the power at the distribution board and the looking for the difference is really important. Even when having done this I do have the slightly (bad) habit of intentionally bridging live and neutral because if there's a pop and a circuit breaker kicks in, I'd rather that it do this when I expect it!
Strickly, you should also check your tester immediately AFTER checking the circuit - to ensure that the tester didn't fail JUST BEFORE,or during) your test ! Pro's will have some independant voltage souce -or use knowingly energised circuit.
@@tridentmusic5570 You are right, but I haven't seen anybody doing that, except the guys who work in secondary substations. In household installations it is more common to create an intentional shortcut after testing just to be on the safe side. At least that's the case for Germany.
Cheers
Andreas
@@andreasbentz6106 Agreed.
I'm in my 50's and did a 5 year apprenticeship as an Electronics Technician when I left school. I then became good friends with an Electrician who over the years taught me a lot about household electrical wiring etc. As a result I feel that I'm relatively competent as a DIYer and myself have seem some hacks that were so dangerous I physically shuddered at them. Every bit of work I've ever done on my house electrics, I have an electrician come out and check it. When I built my workshop in the garden 20' x 10', I fitted a 20 socket ring main and 12 light ring. I ran the Armour cable to the CU and had an electrician come check it and connect it up. He said he had no qualms with connecting it and certifying it as the job was good. My point isn't to "big up" my skills and knowledge, but to point out that not all DIYers are terrible, some of us actually go out of our way to make sure we do a good job because we realise that our lives and the lives of our families are very much on the line.
Indeed so. I'm also an electronics engineer and would never make any of the DIY mistakes mentioned here. I also know that it is not inductance that causes a rolled up extension lead to get hot! Unfortunately Part P has turned us DIYers into criminals and, by making the relevant standards inaccessible to non qualified persons made it far more difficult for those of us trying to do a decent job to do so.
The issue for you, that today, some of the work you did is considered _notifiable_ and by law, the Building Control department of the local council has to be notified.
Even if you are competent as a DIYer, you still have to notify the Building Control and they will tell you what certification requirements are needed.
And as you don't hold any formal qualifications, and no membership of NICEIC or NAPIT, then they will require that a qualified electrician inspect and sign it off as being compliant to the wiring regs.
So I think it is important to not send out a message that anyone can just go along and do their own electrical DIY and get an electrician to sign it off.
There is more to it than that.
@@John_LNo, it is not true that Part P has turned people into criminals.
I have repeatedly seen statements made by even electricians that say people can't do their own electrics.
That is not what Part P of the building regs says. Part P says that the work has to be done to compliance of the wiring regs, and be certified by somebody competent and it talks about notification to the building control department.
@@deang5622 This is true but by making the said wiring regs only available to certified personnel the effect is to make it nearly impossible for the conscientious DIYer to do a compliant job. And the DIYer is criminalised unless his work is inspected, even if it is not notifiable work. The practical effect is indeed that the DIYer cannot do his own electrics, no matter how competent he is.
@deang5622 yes but you obviously missed the part where I said it was inspected and checked/tested by a qualified person who then issued the appropriate paperwork. the work I did on my workshop was done back in 2011and as I said, I had an electrician come out to connect it to the CU, I left all the socket fronts off and the lighting covers on the flourescents off so he could see the job I had done and also marked out my cable runs that are behind the OSB that lines the inside, I also have a couple of covers that give easy access to some of the areas where the cable runs incase I need to do any work on it. He was happy enough to sign off on it and to connect it to the house CU. I ran the Armour Cable and routed it to the CU in the garage and again after testing it he was happy to sign off and complimented me on a good job. The result is, I have an ele tri ally safe workshop that has been in use now for 13 years with zero issues (except a small leak in the roof I just had to fix🙄). I have also had another electrical inspection about 2 years ago and they checked the workshop because its connected to the household CU so included it as partnof the house and again had a clean bill of health. Based on all this, why am I breaking the law? Yes I did the work, but didn't make the final connection and it was all tested by a qualified person 🤷
The cord is not about induction but simply resistance. When it is wound up it cannot dissipate heat and cool. Once it heats up the resistance increases and it heats even more.
All those thermal protections, as well as fuses and circuit breakers are in case an overload happens. They are not some permission to load as much you can and rely on them to cut.
Absolutely correct! At any point in time the current in the L and N conductors will be flowing in opposite directions and are physically very close together so the magnetic fields cancel.
I was very suprised he made that mistake .
The resistive heating is an issue also, if wire is heat insulated. Adding heat insulation to a wall or ceiling without remaking electric installation may be fire hazard.
Even more important in boat or camper. Low voltage cabling uses high current, and hiding a 1,5 mm2 wire inside good foam insulation and using it just with 120W may be enough to cause a fire. With battery a shorcut ends up to red hot wires very quickly, and insulation can melt and cause short circuit.
@@callumcurtis15 Yes! Especially when he's criticising DIY installations from an expert position - Physician, heal thyself!
@@stpeter7432kind of true, but only at low frequencies. I know I'm nit picking.
Electricians trade is like no other for slagging off everybody else's work except their own.....
This happens in all blue-collar jobs.
Doesn't happen in professional services, eg medical or legal.
Probably indicative of education.
Jordan loves to slag off the customers (DIYers)😂
There is some reason for it I'd argue, especially when electrics are one of the most dangerous things one can play with in a house, alongside gas. It has to be done right, there's no room for corner cutting or mistakes.
@@chuckmaddison2924absolutely does happen in medicine and legal. Humans are humans.
I've employed several 'qualified' electrical contractors and had some really shoddy work completed. Be carefull not to employ an electrician that doesn't know what he or she is doing.
Coiled extension has current running in opposite directions (hot ("live") out, neutral back) so induction is cancelled out.
It's simply that with enough current the cable heats and because it's coiled the heat isn't dissipated as it would be on an uncoiled line.
Wow so that was wrong squared. The induction was not the problem on the extension cord
It was simply the thermal resistance of the cable to air.
Another common mistake is pushing the wire too far into the terminal so that the screw is tightened onto the outer insulation of the wire rather than the copper, thus no connection. Particularly bad if done to the earth.
I get cable pulled from domestic kitchens being refitted and this is probably the most common issue after terminal blocks wrapped in insulation tape.
As a DIYer, after seeing this, I feel very competent in my work. I use a very old and reliable Fluke multimeter for various tests, would never dream of all the things you've covered here so I must be in the 'safe' zone (although I have electrocuted myself twice but isn't that to be expected, the first time was as a young child with poking wire in a socket🤣).
After visiting my loft, I can say that it's a mess, clearly the electrician wasn't to our standards.
I have a 10 meter EV charger cable which I always unwind regardless how close the car is, just to me, common sense.
Some of those DIY fails like clipping I've also seen from "professionals" trying to rush a job :)
Very true!
As the legendary oil rig fire fighter Red Adair said “If you think that hiring professionals is expensive, try hiring amateurs.”
Very, very true - in many industries.
Love it. I am going to use that more with my Senior Managers in Health Care...
Red Adair in a rare moment off from dancing with Ginger Rogers.
Err how can you hire an amateur; only means somebody isn't be paid!!!!
@grahamheath3799 there's always one.
Good call out with the coiled-up extension lead. That is something I don't see enough people talk about, to be honest. (As others have pointed out, it's not actually about induction, it's actually just about not having enough airflow to properly cool the wire, but the main point is still a good one.) And yeah, you had a pretty nice one there with a thermal cutout and everything, but a lot of them don't have that. It doesn't even have to be one of the really long ones with their own carrying spool like that one was, just a plain extension wire that somebody has left coiled up in a loop sitting on the ground can get a lot hotter than it's supposed to if a decent amount of power is pulled through it.
And the reason you don't want extra exposed conductors even inside a box is because sure, it works _now_ but then later somebody comes on and moves something around and something falls on one of them or one of them gets pushed into something else and all of a sudden you've got a dangerous short. It's not just about getting things to work right at that moment, it's also about making sure they won't go horribly wrong somewhere down the line, too.
Oh, and with the screw terminals, one other important point, IMHO: *Always tighten them twice.* Screw them down initially, then move the rest of your wires around, get everything properly in place, and get ready to button the whole thing back up, and then go around and _make sure all the screw terminals are still tight._ It's amazing how often they can become loose just from moving stuff around after you've initially tightened them (part of the reason I much prefer other types of connectors like the WAGOs when they're an option).
I did some home wiring to extend my power into the loft back in 1998. Before my parents bought the council house... About 6 months after when they were buying.. They sent an electrician out to check the house wiring as part of the purchase agreement. We forgot to unplug a few items in my wiring extension and his test equipment showed the plugged in items. So we had to go up and unplug the Railway... (Had a model railway in the loft and floor boarding.)
Anyway he was impressed by the wiring and confirmed it was one of the better installs he had ever seen. Asked me if I had training or had worked as an electrician. (part of my education had included basic circuit installation.) So I actually got praise for a good install by the electrician, he said it was really rare to see a DIY install that met any codes.
I did question about running a light circuit off a Ring main through a fuse box to 1.5mm wire. He said it was fine.
The loft had an installation of wiring previously into the loft.. But it was literally from the last tenant, they took a plug socket and cable into the loft to power 2 lights and a heater.
I took all that out and put 4 lights up, strobe bulbs ? I forgot the name. (live in Denmark now.) I built the ring main up there so we had 4 sockets, extended out of the ring main for the upstairs. Sunk the wiring into the wall. Came up into the loft and pinned ever 6 inches. Fuse box by the entry hatch and off the fuse for the lighting circuit.. I had smaller wire for the lights, through a switch. So you could go into the loft and turn on lights. Power was always on to the sockets.
The house passed the Electrical inspection anyway, after main fuse box was updated from fuses to RCD's and moved from a bare panel above the fridge into a sealed panel above the fridge. (my work did not need touching.)
Back to school for Jordan with the "induction" heating... If it was wound around a metal core with a load more current at a frequency in the kHz, then maybe...... Boring old resistance heating I'm afraid. Do your media team not fact check?
Well, the explanation was not quite right, but the actual issue and main point is still entirely valid, so I'm still glad he mentioned it, at least. Coiled up extension leads can get a lot hotter than they're supposed to (really just because of lack of airflow for cooling), and that can actually be a real problem in some cases, so you definitely should always uncoil them and separate them if you're pulling any kind of significant power through them...
@@foogod4237 when you say “not quite right”, you mean not even close…… the same outcome does not not justify an incorrect explanation. Especially so when the whole video is berating “DIY” practises in the first place. And even more so when these supposed DIY practices have plenty of precedent of being done by so called “professionals “ in the first place.
There are two different things in this which the video presenter has confused.
1. Induction coil
2. Solenoid
We don't have 1 here, we have 2.
And in the case of 2, we actually have two solenoids interwoven, comprising one turn of line one turn of neutral and this then repeats for the full length of the solenoid.
Both line and neutral coils are wound in the same direction, so both coils will produce a magnetic field each in the same direction if the direction of the current in both coils is in the same direction.
However, as we know, the line and neutral currents are in opposite directions which means the magnetic fields are in opposite directions.
Assuming no earth leakage, then the line and the neutral currents and the same magnitude.
The net effect is the two magnetic fields are equal and opposite and cancel each other out.
So no magnetic field.
It is very common for electricians not to understand much about solenoids other than they create a magnetic field.
I have seen had an argument with a sparky on this channel that tried to argue the inductance was zero and quite firmly stated that the inductance is not related to the physical properties of the coil.
Something seriously going wrong with their education in inductance and solenoids.
But I guess, an electrician trains electricians. So the myths perpetuate.
@@deang5622 Can an inductive or capacitive load shift the current on the return line?
The whole plugging extension inti extension doesnt really apply here thats why the fuse exists. its actually quite hard to overload ive tried just out of interest. Now all these are common sense i genuinely dont get how people think any of this is ok. Ive seen people do it and my mind just cant comprehend how they think its safe.
You are missing the fact that 'common sense' is actually rare and becoming rarer, often pushed out of the situation by dumbass ego.
Also 'idiots' are quite willing to bypass fuses because to their mind a blown fuse is because the fuse is faulty, like a blown light etc, therefore they jury-rig a fix because of that perception of 'what do these so-called 'experts' know? It doesn't blow when I fix it . Therefore I know better than them. It's false logic, but ignorance and ego drives them onwards. QED.
Had a new guy work at the electrical contractor company I was at.
He was put on a job to wire a fire alarm.
His work was shocking no idea how to clip cable straight.
But the worse thing ever to get a cable from one room to another he drilled a hole to outside wall,run the cable along the roof guttering and drilled through again to adjacent room.
That was about 40 years ago and seen lots of crap since, he didn’t last long.
Great video Jordan. As a DIYer I think the advice you're giving is spot on. Discovered the coiled extension risk the hard way as a kid in the 80s (those were the days!). I think most competent DIYers, and professionals are already aware of these points but make mistakes out of haste, lack of the right tools to hand, or a an optimistic approach to risk rather than ignorance.
The wound up extention could also apply when people are using their vacuum cleaner with the cable wound up inside, not fully pulled out(like a Henry type vacuum). I used to service vacuum cleaners for a cleaning company as an apprentice and we regularly replaced the flex cable inside the vacuum cleaners. The cable had melted together the outer layer inside the coil causing the cable to not be fully deployed. This of course caused a further issue with further melting. Fortunately we never had any fires, but cleaners would complain the cable could not be pulled out properly. We would try to educate the cleaners to "fully pull out the cord" when using the vacuum.
That’s never happened on a single vacuum I’ve ever encountered.
Well done on making this video Jordan. You are educating the masses to their mistakes and making people more aware of how dangerous their action can be. I was an electricians mate and have seen some of the bell wire to lights in attics and sheds or even two core and cpc outside and a family memeber even had two core and cpc on a catenary wire from house to shed lol. I soon isolated the circuit and swapped it out with some Hi-Tuff along with fitting a metal clad socket in the shed. I would always crimp my flex cable before terminating with a scew.
As a DIYer I don't often see other people's work, but having moved into houses that other people have worked on, the one that I see the most is just that the cables behind sockets and light switches are far too short, like you unscrew a socket to paint around it and it can barely move.
Using snips to remove the outer sheath and cutting into the inner insulators and partly exposing the copper. Not always visible but a real danger for getting a shock.
That’s a good one too!
Yep, it's a very easy thing to do too. I love my proper wire cutters but even these don't work on all cables as well as I'd like.
I had a case where the customer connected a 3 phase motor by himself and did just that. He made accidental cuts into two-phase and neutral insulation. Since there was still air for insulation, it worked.
It had a motor protection breaker on the circuit and it started shutting off regularly (once or twice a week). So he decides to change the circuit breaker, at first it seemed to stay on a little longer, but soon the same pattern. A little later he also replaced the motor, still the same.
When I went there I suspected insulation, but insulation tests with 1000V did seem ok. I still decided to open everything on both sides, to check cable and connections and that's when I noticed these cuts. Fortunately, there was enough cable to cut this section off and do it again. Since then, no problems. He checked that motor connection box dozens of times and me and other guys with electrical backgrounds checked the box also and saw nothing. Cuts in insulation where straight, both halves were kept together so no exposed copper, no moisture and no signs of a short circuit.
I well remember a case when I was on a Tech Theatre Course back in the Eighties. The theatre was adjoining the old Victorian house, and while the LX had it's own supply, other equipment tended to be run from the house's supply. On this show the whole stage had been painted with size paint and then sealed with Emulsion Glaze (PVA). During the night there had been a leak and the stage was soaked, walking on it would rip up the paint, and that was a key part of the show. So. Every heater we could find was put on stage to try to dry it before the afternoon Matinee. Couldn't even mop it, it was so soft!
So the extension cable (at full length), got hotter and hotter, then blew the fuse. The Chief LX on the show went to the fuse box and pulled this huge, palm sized ceramic MK fuse out without thinking, and got MK branded into his palm. Nasty!
At least he was able to pull it out. I have seen this things get welded in place
In the early 90s I was employed as a test engineer on new build and general construction work.
I could write a book about this. Couple of quick ones . House light circuit wired in telephone cables.
electric shower wired off local light circuit via a spur in the bathroom which had a bit of a nail as the fuse .
It's not inductance that overheats the extension lead as the fields will cancel from live and neutral carrying currents in opposite directions - it's a lack of thermal conduction to circulating air of which three is none when it's tightly wound.
That implies the cross sectional area of the wire is really under sized then.
@@chrishard7616
It's the right cross section when unwound and in free circulating air. When tightly spooled the I²R loss is too high when concentrated in the small space. You could have a thicker wire to reduce the i²R loss so it doesn't overheat when tightly spoiled but of course a thicker wire wouldn't fit on the same size spool and you'd end up with a much bigger, heavier and more expensive extension reel. These things are always compromises. It will work at 13A when unspooled and perhaps only 4A when spooled (continuously) or short periods at 13A to limit temperature rise, perhaps relying on a thermal cut out switch.
Great stuff.
I've got a Jo Jo extension reel from the late 80s with thermal cut out. Yes, still working fine.
I remember, many moons ago, when we had a call out to house where the little girl had got a shock. To our utter disbelief, the DIY clown had wired the lighting circuit, on the surface, with the very old purple fabric twin flex cable with uninsulated staples to the wall and ceiling, even the excess cable too!! The little girl got the shock from a live staple near the switch!! I've also come across a whole house wired in bell wire! Had another occasion where I went to help another spark in the middle of trying to rewire a house. I couldn't believe the state of the place, the other spark John was trying to get under the floor in the lounge. RUG nailed to floor, then Lino, then 8x4 board nailed and then tongue and grooved floor boards-different from the norm, in that the boards were grooved female both edges and the tongue was a METAL strip between them!! Sorry to say I left when the woman complained about the mess!! Gave up on house bashing years ago. Good luck you lot!
Seen a few qualified electricians just lash cables all over the loft joists unsecured. Done with the right mindset a DIY job can be done with more patience and care than your average electrician!
Very true!
Yep, my brand new house was a bit like that in the 90's. Some cables were clipped but many just strewn on top of the insulation.
Exactly the case here. Loose cables just flung over the top of the joists, not run properly in any way. Add in the person who put loft boards in the loft not knowing to screw the damn things instead of nail them and to interleave the boards and I had a flooring mess. What made it worse was because of the half-arsed wiring job done gaps had to be left in these already flimsy loft boards and the "fix" was to just leave a gap and dump another board over the top and nail that in place too. I'll be redoing all that wiring at some point, running it properly through the joists but it's a tedious task - it's a flat and it's both sockets, lights and storage heaters that have been wired like this. For extra fun I found that one of the storage heaters had been wired into the lighting circuit in the distribution box. Genius.
In some countries this seems the norm. It brings shivers down my spine. Why not just spend a couple of minutes just to make it tidy?
"Done with the right mindset a DIY job can be done with more patience and care than your average electrician!"
Yes, that's very true. Anything I've done has been permitted, and with extreme care and attention, precisely to the regs. A better job than a pro electrician that does the minimum.
What pro's don't notice, is the excellent DIY, because its indistinguishable from a professional job.
Hi Jordan, I enjoy your video's but I am not an electrician I only do the basics, one of my biggest electrical pet hates is wrong size fuses in plugs about a month ago we bought an electric hand held food blender only 175 watts but fitted with a 13 amp fuse that to me is a safety issue by the manufacture and against the warranty I swapped the 13 amp fuse for a 3 amp it works fine its just down to basics. I can understand with power tools a 400 watt drill will be fitted with a 5 amp and not a 3 amp because of the start up of a motor.
Great video thanks for showing Take care
The fuse protects the wire not the power draw of the device. Although you may have a low wattage it may well have a higher inrush current and that could blow the fuse. Unlikely with the figures you have given and fuses have a degree of inrush allowance.
@@davideyres955 Hi David, thank for your reply, but would a 13 amp fuse blow on some thing with very little power if there is a fault on the appliance the cable is only 0.5mm twin flat flex, I am not electrician but I was told to use the correct fuse for the wattage of the appliance, once again thanks for your info
@@shaun30-3-mg9zs The fuse should be sized to a maximum of what the power cable of the device can handle, or 13A, whichever is smaller. Most appliances have cords which can handle 13A, even if the device itself is never intended to draw that much, so a 13A fuse in the plug is fine (it will still trip before anything gets hot enough to cause damage/fire). However, if your device has a cord with 0.5mm^2 conductors, then that probably shouldn't go over 5A or so, so yeah, a 13A fuse is arguably wrong in that case.
@@foogod4237 Thank you very much for your reply. just concerned
In our first house I was swapping out some ceiling light fixings.
So, I turned off both "Lighting" Fuses at the box.
But, in a bungalow, with full access to the cables in the loft space, I quickly found that the bathroom lighting was hooked into the socket ring. Quickly and sharply.
Learnt an important lesson about other people's work and the value of test equipment that day.
similar situation where i found out the garage lights were running off the kitchen sockets ring.
What I'm missing with the screw on plug is a longer earth wire. I've been taught in school that the earth wire should be a bit longer than the live and neutral. That way, in case the live or neutral pop out, the device is at least still grounded.
thats why the earth pin is at the top and theres a space by the earth pin terminal for the earth wire to coil around a bit, so it can be a bit longer and the extra length fits in that space.
Not to talk down what electricians do, but a DIY'er is easily capable of doing the basics in a typical house - wiring radials or ring circuits for sockets, lights, downlighters etc, to the exact same or likely better (because you always take greater care over your own stuff!) standards of an electrician.
Thanks! This was great to watch and know
Went to a LAN party back in the late 90s. A lot of computers, CRT monitors, and even though the extension cord was unwound, the jacket laying on top of the pile of unwound wire still got burn marks, probably because the extension cord was under dimension for the load. Be careful out there.
7:45, use ferrule crimp ends (shoelace crimp). Not only do you crimp once with your tool, the screw itself will compress the wires against the ferrule and they won't separate or spread out, ensuring a solid connection. I don't know why people don't use them on stranded wire outside the EU. Every time i see one without a crimp, I cringe.
Must admit I like using ferrules - got some a few years ago (with crimp). While not an electrician as a retired electronic engineer I know more than most.
@@apk55 Discovered simple ferrules for flex termination years back.
I need two on the second meter tails i just upgraded (from the insufficiently sized cable the previous diyer did). But I'm not going to buy a tool just to crimp two ferrules!
Professionals work on live boxes. You just have to be mindful. Otherwise you're working in the dark!
@@imaginitivity7853 I crimp hundreds of wires every day since I'm building automation cabinets with PLCs and drives and other stuff, so I really need it, but on installations with solid core, I guess you don't really need it. But my point stands. Multi core wire should be always crimped unless connected to a spring terminal. Push terminals and Screw terminals need the crimp.
The golden rule is to make sure there cannot be any stress/pulling on individual wires (causing them to get loose from their connectors, arching, and burning down the house). This is why the outer sheathing of the wire needs to be clamped down. When pulling the cable, the stress is taken up the cable as a whole and not the individual wires that easily risk coming loose from their connection.
One of the craziest domestic instal horrors I found was figure 8 VIR with nails through the centre as clipping. Some of the nails had arc marks either side and the (Wylex off course) rewirable fuse carriers in the CU were so spattered with vaporised copper that they conducted enough without any wire to still show live on a high impedance tester.
As someone who's education was electronics, I knew all these things, even the last one :p. When we were searching for a house, we found one where a 3-fase 400V 63A socket was installed right next to a shower, basically the shell of the socket was touching the shower's glass wall. Quite risky if you ask me. And another house where no ground protection was installed anywhere. If you wanted to fix that, you'd have to tear down all the wall decorations and ornaments to replace all the cables. So many houses where nothing is done properly.
Here's one I discovered. Found an "extension lead" made by fitting a socket in a VHS tape box and wiring up to mains. My heart nearly skipped a beat when I spotted it. Safe to say it was disposed of very quickly and replaced with a correct extension lead. I'm no sparky but I didn't need to be to know that was damn dangerous. To make matters worse it was powering an old CRT TV in a kids bedroom. Makes me wonder what they were thinking when they fabricobbled that together!
i saw the pic for the vid and thought... "jordan is lethal?!" 😱😳😂😂😂
good vid! bit of an eye opener!
😂😂😂
I think the number one mistake people make with all of these things is not thinking thru what could go wrong. "Pros" are taught about the common (and maybe uncommon) failure modes for various things and the ways to avoid/mitigate them. DIYers have to think of them themselves (and will often miss them). DIYers who stop, think, research and question both the how can I make this happen, and the what can go wrong can do a good job. I suspect there's not many of them around though!
Another good and informative video. Thankfully know them all and always over cautious.
Often shocked doing PAT at work. Amount of new extension cables where we fail the plugs out the factory and refit or reterminate wires.
Nice to know as a diyer I've not made any of these mistakes. I even have my own live tester beeper. A note on the last one, some extension reels only use the trip/reset on 2 of the four plugs, well mine does anyways(could just be broken), my kid used a 2kw heater on the wrong socket. It didn't trip, nearly caught fire and also melted the wall socket the reel was plugged into! In the other 2 it trips very easily with the heater unless fully unwound.
In Santo Domingo (Dom Rep) almost all if not all wires are connected by twisting and taping over.
The country hasn't gone up in flames yet. Standerdizing connectors like wire nuts or wagos is to ensure a minimum standard.
But not using wagos/nuts doesnt mean bad.
Thanks for some great tips. Thankfully, I was already aware of them although the coiled cable was a quite scary. When removing ceilings on my old house I found "rewired" lighting meant, in some places, a few twisted wires with a bit of insulating tape wrapped round them... 😲
As an electrician of over 50 years experience I was taught as an apprentice to twist wires together before screwing into terminals!
Still the procedure in Australia.
pretty sure efixx still show it.
Stingers(leaving a strand of stranded wire sticking out), Shiners( stripping too much of the insulation off individual conductors. Running Romex in to a metal box or panel with out a plastic or metal romex connector. Open splices, cutting off the ground conductor on a romex cable, not tightening the wire nuts properly, not burying underground feeder cable to the correct depth, using too large of a breaker for their wire size, using extension cords for permanent wiring. These are common things that I see DIYers doing all the time. Thanks, Russ 29 years in the Electrical Trade from across the Pond.
Im in the us and wire nuts have never sat right with me. Never liked them. I recently discovered the snap connectors and absolutely love them. I use them everywhere.
I had to do a lot of electrical work on my house and i took the time to search out quality sockets and sundries. I also made good any poor quality wiring i saw and replaced the choc-block with proper junction boxes. When tightening connectors with a screw driver, nip them up and then again a day later. You'd be surprised how much it will have relaxed in 24 hours.
I wanted some two fluorescent lights fitting in my shed years ago and didn’t know how to wire them. My dad suggested going to one of his neighbours who was a sparkys mate. He asked what type of fuse box it had and I told him the wired fuse types. He took me in his shed and wound loads of fuse wire around a dolly peg. As he handed it over he said ‘ I don’t know how to wire it but by the time you have used all this, you will have figured it out’. I was absolutely speechless!
Twisting wires together doesn't have to be bad.
When I do it, it's with them pointing to each other (Which takes some skill), then solder, and heatshrink it together.
I also don't usually do it with mains.
Daisy chaining extension leads also doesn't have to be bad... as long as you count the current of what you're plugging in.
Definitely do not plug an electric heater into the end of a daisy chain of extensions, like my brother did.
It's not induction, just resistive heating
I did the twisting solid, and stranded wires and swapped colors, and also didn't always clamp. Thankfully no issues. It's just double work, cause now I'm re-wiring everything. :)
A useful video showing your experience thank you, sadly I've seen most of those from electricians as well, including having my oven nearly go up in flames due to a loose connection and leaving live cables hanging from the ceilings (that hurt). Concerning the failure mode from an extension lead, I thought that's due to the cable not being able to shed the heat due to being wound up. I quickly calculated (so sorry if there's a mistake) that the inductive losses from that situation will be along the realms of 20W, (I think the inductor will be about 4mH), assuming that's a 25m 1.5mm^2 extension lead the resistive losses will be around 80W. (Quite happy to learn and be corrected, I mean this is in an educational learning sense not the standard YT comment way :) ). The other thing I've always done is to make sure the tester works before I rely on it to show a null result, but I use a multimeter, I don't know whether the tester you suggest has a built in check for itself.
We had an immersion heater that had been wired in the house with 1mm cable. Fortunately we never used it as the boiler provided the hot water. I was only discovered when we had a board update.
screw fittings don't go loose due to AC (as opposed to DC), it is thermal expansion and contraction when power is turned on and off which can cause the screws to loosen. if the screw is not tight enough to start with, you can get arcing which will excelerate this and potentially cause a fire.
I've seen speaker wire used instead of bell wire, which is also really bad, as apart from the lack of earth or secondary insulation, the primary insulation is usually not heat resistant and easily melts, exposing the wires. I've also seen "professional installation" wire power supply colour changed between consumer unit and switch from red to blue, or white, or red making it impossible to rely on the wire colouring.
As has also been commented, the coil extention wire overheats because of lack of air cooling, not inductance. As the live and neutral is in the same flex, flux will cancel out, as the current is going in opposite directions in the same flex. The conductors are the same size and will have the same voltage drop accross them but in the opposite direction in a length of flex. (This is why a clamp current meter doesn't measure current when put over flex containing the live and neutral. it uses electromagnetic flux to measure current)
Twisting 2 wires of the same type (!) together actually gives a larger contact surface than most cable connectors. With a bit of a solder, this surface can even be enlarged. So, if you don't want to decouple those wires anytime soon, it's very fine to do proper twisting.
Interesting to see how different DIY electrical projects are in the UK versus in the U.S. In the UK seems most of it is about messing around with plugs and cords, which really isn’t a thing here. I guess that’s because of the need to deal with the fused plugs etc. Here, I’m running house wire, installing receptacles and lights and the associated junction boxes, and new load centers.
I’m a diy enthusiast and became one so many years ago because of what I saw ‘professionals’ do. Poor quality of work was the main reason but also the cost. Over 40 years I have become a jack of all trades, who has high standards way above what some contractors have. Just look at the quality of work put into new builds…. Shocking.
I've been told that the reason solder is not used in house wiring is that it would let go in a fire, with very dangerous results. By the way, Wagos have made it to the USA. I find them very useful on the test bench because it is so easy to make a good connection and then undo it non-destructively.
This is why I don't like the tamper-proof/non-serviceable multi-socket Extension leads as these often use solder joints (to stop people re-purposing them I guess?)
I had one recently in a school I work at (in the UK) where I took it out of service because the outer sheath had escaped the cord grip and it had an intermittent supply of power to the sockets. Out of curiosity, I broke it apart just to see how it had failed and it looked as if it had been getting a bit hot as the live connection was barely still connected. In the bin that went.
The problem is, where it came from, the room (a faculty Staff room to be more specific) doesn't have many wall sockets so Staff have been using these extension leads where they want to plug in more devices. The other problem is that we have Staff who aren't particular about what they will plug into one extension lead ranging from any one or more of Fridges, Toasters, Kettles & Fan Heaters!
i guess when you're house is burning down, you don't want it burning down a second time :P
One thing common in bodge jobs especially around surveillance cameras is using Ethernet cables for power by directly wiring a few cores of the Ethernet cable to either a DC power supply or even mains voltage. The proper way to supply power using an Ethernet cable is to use a PoE injector / switch with a PoE capable device.
And that works because PoE typically uses 48 Volts, and so the current flow (which is what drives heat dissipation) is only a quarter of that used with a 12 volt device for the same wattage.
Got called to a drive through sign not working. Has been installed for over a year. The underground was compromised and decommisioned. The mains feeding the first drive through sign (before it looped off) was an extension lead with the ends cust off instead of proper cable.
I’m aware of these issues so have always been extra careful and do it right.
But hopefully soon I will get the house rewired as my oldest son is training as an electrician as he intends to do this for me.
Good safety tips! My only objection is how you put a stranded wire into a screw-terminals: in my experience it's much better to twist stranded wire when connecting them to a terminal. The tab inside the terminal will squish the twisted wires evenly, providing a physically stronger connection, with more contact surface.
Also always make sure your voltage detector works on live wire before making sure the wire is not live. Hopefully said already but does not hurt repeating.
Something I see over here in Australia, is people cutting down the extended earth pin to make 15A welders fit in a 10A socket.
Absolutely bonkers. Just get a electrician to wire in a proper 15A socket to run it on.
GOD your first one 'The Twist' I'm a DIYer and would NEVER do that, I would prefer to wait for a day and buy some Wago's off Amazon, and anything out of my league get a sparky in!
The "connect all the reds" things is why for a long time now I arrange wiring so that there is only one unambiguous cable at each outlet. All junctioning is done separetely from the outlets in junctions boxes specifically for the purpose.
This had me looking at the smart garage door controller (basically a wifi-controlled relay) I recently bought - all low voltage (5 Volts DC) so it's not a safety hazard as such, but the signal and ground cabling they use to connect to the main door control box is just a piece of random two-core flex with the outer sheath stopping well short of the device enclosure - no strain relief at all on the control cables, the USB power cables, or the door-edge sensor cables. I fear it's not long for this world.
In reality why is there any issue daisy chaining 4 way type extensions, given, in the UK where this is filmed, each plug (including the primary extension) has a 13A max fuse, the most you could pull in the entire circuit is no different to it being on it's own. The fuse will blow and assuming the extension lead is suitably manufactured and tested, there should be no additional risk.
I'm pretty sure that warning been imported from the US...
The issue is that many of them aren't suitably manufactured and tested. People buy stuff online from wherever they can find it cheapest, and that results in a lot of really poor quality. How easy it is to find a partial earth pin in plugs for all kinds of things these days is sort of scary, & switched multi-gang extensions can be particularly gnarly with switches not rated for the mains or being spongy & audibly arcing. The fuse may eventually blow, but that doesn't mean you won't get heat build-up and scorching before it happens.
@@nightcatarts fair point but if it’s cheap tatt then a single one is just as likely to go up in flames.
@@craigmck7271 Very true, but that risk increases if the cheap one is first in a chain.
13 amp fuse won't blow till you pull 26 amps or so through it, though. And the ring main will have a 30 amp circuit breaker. It's quite possible to get wiring running hot without the fuse blowing. If that wiring is enclosed somewhere - say run under furniture, tucked behind curtains - then the heat can't escape, and can build up to 'burning down the house' levels.
The ceiling rose is the thing that confuses more DIYers, than probably anything else.
I've been called by a few panicked DIYers, where they've charged in and disconnected, only to find more wires than they expected.
Had to sort that one out for a neighbour recently. Seemed puzzled that I could sort it while chatting about something completely different.
@@Graham_Langley It's easy enough to sort out, if you understand how the circuit works.
That is the trouble they buy a new light fitting from DIY store and it wants L, N, E and you pop open ceiling rose and there are loads of wires!
A friend did a welding subject as part of a farming course c.1965.
One participant asked why 2 wires were needed. "One for the volts, the other for the amps" said the instructor. (!)
I did not know about uncoiling extension leads. Thanks so much for this.
It’s not due to induction, though.
I have seen some stuff in my time from when i started electronics in 1983 tv repair - some of the engineers were mad as hatters, i am obviously used to working on live things some voltages in old tvs were 20000v.
then i have worked on UPS and invertors some pulse width modulated on 3-phase, also wired up two of my own houses workshops and garages. I have worked for over 25 years for an engineering and electronics firm where we wind transformers, electrical assembly and years ago used to make valve amplifiers and valve radios, but that was way before i started. I do ike fault finding though.
Very nice good advice 😊
Yes, do be careful getting pulled off in the loft, insulation fibres get everywhere.
As an amateur, I am glad to say I knew all of the items you displayed, its an age thing, I'm 71 and was taught well by my father. To me some of the items were very obvious. Great educational video as usual.
My worst DIY mistake was putting a bolster down between two boards and cutting through a cable that had been notched into the joist. Rookie error!
I recently completely refurbished my house, and made sure that all cables went through holes in the joists. But then, my Dad was an ex-sparks who taught electrical apprentices - he *never* notched a joist.
The wire nuts can be a good connection if you pretwist the wires and if your going to solid to strand push the stranded in first than the copper than twist together. Enough practice you get used to it i prefer copper crimps and nylon caps (Buchanan and the 4 point crimp tool)but am coming around to wagos
Speaking of bell wire, I've been known to use coax in the past 😂 of course I understand the risks and took precautions, it was just what I had at the time for a temporary fix
Best one I've found was a doorbell transformer wired into the back of an outlet using figure 8 shielded audio cable, he just mashed the inner and outer of the shielded wire into one conductor on both sides, effectively turning it into twin flex.
The worst part was her was a licensed electrician, and maybe worse, he did this to his parents house! (that I then bought)
I bet there is some other 'greats' yet to be discovered in this house.....
No. 10: Effectively, this is no inductive coil. The magnetic fields compensate each other as the current in live and neutral wire flows oppositely. it's all about losses due to the copper's resistance.
Plenty of solar panel fires where the installation was carried out by professional electricians.
Plenty of factory fires put down to electrical faults , that's not an installation done by DIY.
As an electronic engineer , I have seen many machine tools damaged by electricians who think they are qualified to work on anything from a torch to a nuclear power station.
As a professional, I have stuffed up. No one is perfect. The professional makes far fewer mistakes, because of the long training and continuous learning of the day work. Unfortunately there are some who know better, but take short cuts at every turn, not good for the trade.
@@rodbickeNo. He is criticising electricians, not professionals.
Specifically electricians.
Electricians that think they are experts
Electricians should not be making safety critical mistakes.
It is not acceptable to make safety critical mistakes and say "Oh it happens". That is not good enough.
I am in Bulgaria..all these faults are standard practice here. All the wiring in my house refurb is heat and fire resistant, When the '' technician'' from the elecricity supply company came to check the installation before connecting the house to the meter box, (3 phase, 385 volt supply) he asked me what all the ''fancy orange cable'' was for. 😊
Nope not committed any of those. Came across a job where some one used two independent single pole breakers for a 240 Volt service not kosher.
But the worst to date was a splice in a 120 Volt 20 Amp circuit NO box using some weird wire clamping hardware. This was in a attic space and the
splice had plainly failed and burned up very lucky no house fire resulted.
I'm a car mechanic and i can tell you there are countless cases of bad DIY wiring in the cars i see every day.
Yeah it's "just" 12V but it can still cause a fire if you don't know what you are doing.
One car i worked on had a custom DIY stereo install, fuse was in the back with the sub and the main supply cable was spliced inside the sill right at the drivers seat. The way they had spliced together the two cables was pretty unique: both ends stripped about 3-4cm and then just placed on top of each other. Three zip-ties held the two cables together at the overlapping splice and then two layers of electrical tape to finish it off.
So if that crappy splice had touched the metal inside the sill it was routed through it would have instantly set fire to the car right next to the drivers seat since the fuse was in the back...
What clips do you recommend for securing cables?
The correct size for the cable!!😃
Wow, i genuinely never knew about the extension reel needing to be unwound!😮
I got a question! I live in Italy and I am currently studying Mechatronics, and I love working with electric and electronics, so I decided to re-make my cellar for working down there, and I had to re-make the electrical system, for having a better one. So I got cables of 1.5mmq that should reach into my cellar, and for my life saver i wanted a 2.5mmq cables, so I just used a mammut for changing the diameter. Now I got cables of 2.5mmq going insde there, and I was wondering: will my outlets work fine? I got 16Ampere one, and each of it there are 2.5mmq cables that are giving the power inside of them. I excuse myself for my bad english!
No magnetic effects of a wound extension lead L & N opposite fields will cancel each other out. Issue is lack of cooling due to insulation caused by layering of the flex only!
here in australia and new zealand it is standard to twist wires together and put in a screw connector.
British electricians hate that when they have to isolate sections of a ring main to try to find a fault.
We don't have ring circuits in Australia.
@@robinbennett5994 completely agree. I think we should use wagos
You would love to see the wiring in Thailand and Malaysia on new build hotels and houses... manually twist the wires by hand and use black tape to "insulate"
Bell wire is as you say, low voltage (usually but not always DC class 3). There is another class of wire not sold nowadays, but I'll bet there is still some around.
I have a set of Christmas lights wired in class zero (0). Single insulated 240 volt rated, you can't buy anything new in it, but there is still a lot around.
I do PAT Testing and have come across class zero. It is fine and still legal as long as it is in good order. Debatable perhaps but can be on classic or vintage items.
My worst bodge I came across was on a Caravan tourer site. The Blue Arctic cable looked odd. On closer inspection, someone had extended the 2.5 flex with 1.5 flex, three bits of plastic terminal block and wrapped in plastic sticky tape. The block had melted with the heat and had gelled together, no short but it was quite hot at the join.
I have seen extension leads with layers of cable melted together into solid lumps due to overloading and not being unwound enough (in a stage lighting gig where the licenced electrician spent the show patching blown circuits - at what cost the show keeps going on?)
Alas some of the pro's are making the same or even worse mistakes. In our house I found multiple live wires being exposed behind ceiling lamp covers. The electrician apparently didn't bother to terminate them properly and used some electrical tape instead which degraded over time which is now a serious risk (both fire and shock hazard I would reckon). Of course I replaced them as soon as I found out by WAGO's.
The two big ones for me that tick me of are, spuring from a spur on a ring final circuit, and not "earthing" the armour on SWA cable.