I wonder if they completely forgot to tighten the screw, stuffed the wire down the back of the clamp or just didn't recheck after the cable had been manipulated. I was a sceptic about the torque screwdrivers until I found out that kitchen fitters are using their cordless impact drivers to tighten screws in breakers because they're...... Joiners. That's resulting in stripped screws (WTF?) and over torqued terminals that still instantly loosened when the cable is moved. Part-P is a terrible thing. Technically speaking the electrical regulations don't actually require a shower isolator, but it's encouraged by the shower manufacturers so their electro-labourers can swap bits under warranty without understanding complicated things like distribution boards (meow!). There's a good chance the isolator was grudgingly installed because the breaker was out of reach.
I had my electric shower re-routed so to speak. It was tripping my RCD Essentially the person before me was an auto electrician and connected the electric shower on the same circuit as some mains and decided to connect it with a bit of solder which is just fantastic /s He's qualified to be an auto electrician but not for regular electrics I'm glad it tripped in a way, because £200 for a fix is better than a fire which costs a lot more in both money and lives. I'll be swapping it out for a mixer shower nonetheless. This is also why you absolutely should get proper sparkies out who know what they're doing. Or indeed for anything else for that matter. Properly qualified people means that a job is done better
Very interesting video ! I was a fire investigator for the police, and these electrical fires are always fascinating. By the way, as an ex fireman I'd advise you to wear an FFP3 mask, especially where MMMF debris can occur.
I wondered what was going on with the surgical mask which is bloody useless for stopping breathing anything in. Maybe they could do with some mask and face fit training.
@@eddwalch-homecraftproperty6613 Yeah, I was thinking the same. Gloves like that, are so stupid. In this case he could as well do without gloves, because most of the contact with all that soot and burned plastic, is happening right at the parts that's not covered (the finger tips). Even for normal work, they give very little electrical protection (fingertips are most likely to make contact with something live first), very little protection to other forms of dirt or oil/grease as well (for example when working on cars) and isn't great for cold weather either. They are really just made for pussies who think heavy work and lifting stuff, hurt their hands
This is a good video for DIYers so they understand how important it is to do everything 100% correct and get it checked by qualified electrician with right tools at the end. The fact it works doesn't mean it's safe.
Just invested in a torque screwdriver! Looks like good experience / eye opener for your apprentice! Just shows how easily something can go wrong months/years down the line
Few years ago new neighbour got locked out, so when i was getting her in asked her why she had moved, she said she had a fire in the fuse box and almost burnt her house out, so was downsizing, googled fuse box fires and they seem to happen quite often, so fitted a smoke alarm inside the fuse box housing cabinet above the front door. and one below it as well to be sure. Also a while ago taking to an electrical engineer who said that the new smart meters are liable to catch fire as so much power going through such a small box will cause problems. Finally even though the power is disconected and fuse removed it still gives me the shivers, seeing you both with fingers in the maze of cables, from when i pushed a Mecanno screwdriver into a 240 set of christmas tree lights, still have that fear of electric now and the huge bang and shock. Mecanno screwdrivers could fix anything when youre niave or just thick..
Very interesting to see the consequences of one loose screw on a high-current circuit. I can see that the 50A breaker didn't trip because the short circuit was on the supply side. I worry a little (as someone who designs EV charge points for a living) that we'll see more of this sort of thing with poorly installed EV chargers. Very few domestic circuits run at full capacity for hours on end, but an EV charger certainly will. Even 32A could get a loose terminal pretty toasty.
Many meters are in a cabinet on an external wall of the house. I wonder; perhaps splitting the supply off just after the meter (before the consumer unit) and passing the charge point feed through a weatherproof breaker (box) on house exterior would be best? The idea being that any fire would be on the exterior of the house.
@@simongreenidge6454 I guess there's no reason why not, if the layout of the property allows it. Wouldn't work in many properties, like mine in Cambridge, though: the DNO's cutout, meter and consumer unit are all together under the stairs.
This is why having a big contactor in the electrical cabinets controlled by a Thermal (HTC) Switch. It will cut off if the cabinet begin to heat too much (before a fire). Also it is good to check the screws once a year.
Or manufacturers could transition to spring/lever terminals instead, 32A is perfectly doable and much more reliable in terms of install quality and longevity.
Heard a story from a friend where he went to a new build job to fault find, the lights in the whole house were flashing every time someone closed the front door or jumped up and down inside the house. Turns out the busbar wasn’t in properly 😬
Damn...that was a pretty nasty burn from a loose connection! I always recheck each screw as the last thing I do before closing up the box (CU) when finishing up.
You can see the fire started just below the rafter that has the initial burning and charring on it in the ceiling, so what ever is just below that was the cause of the fire.
I like what you said about the shower isolator being near the electric meter. Mine is a similar setup with the main circuit breaker in the meter cupboard however the isolator switch is on the wall in my hallway obviously going through the wall into the back of the shower unit. Interestingly it’s a big red switch much like a cooker switch too
Those solid stranded conductors always need a good wiggle and retightening - the installer forgot, didn't know, or didn't care. Tapping off the main incomer tells you a lot about the "installer".
@@YouRich92 Fair point but I'd be mentioning that the boiler needs checking before switching back on, especially what looks like a melted filter... But I suppose electric heating is an alternative!
As a old Sparky, I could never understand why the terminals went to one screw instead of the two we used to have. But hey whats a fire between production costs and they have only just gone back to all steel boards, well I never!. A wet string job as we used to say. 6mm backed by a 60/100a supply fuse- electrician? Toast any one. Good job this guy didn't work on commercial.
Many years ago got called out to a badly fire damaged garage with a bedroom above. The person was asleep in the bedroom at the time and room was filling with smoke. It was noticed by other family members who smelt burning and quickly got the person out of bed to safety. It was a really easy diagnosis of fault. A gas pipe in the garage had a small pin prick allowing gas to escape and directly above was a time switch which switched on at midnight. The small spark from timeswitch ignited gas and it acted as a blow torch straight on to ceiling of garage.
Definitely the shower board for point of origin. Looks like the live incomer and neutral shorted and took out the main fuse. Looks of new plaster board and paintwork needed so may as well take down the ceiling to check the cable above. Always a fun job lads.
For all the yanks like myself watching: 10mm^2 cable is AWG8, 6mm^2 is AWG10. The plastic consumer units always gave me the creeps. I'm happy to hear about the metal enclosure mandate.
6mm2 is not usually sufficient for a load of up to 50A. European 10 mm2 wiring or American AWG8 (8.4 mm2) would be sufficient for a 10kW shower heater.
Agreed. My shower is on 6mm but is only 35.5A. The electrician allowed it because the cable is only 16m and he said the voltage drop would be acceptable. But he did insist on running it on a 32A breaker, so it's on the border 6242B cable, which has a slightly higher melting point than 6242Y (pvc) cable. 10mm would have been better even for my 8.5kW shower.
I have lost count on the amount of slack connections in a consumer unit and shower switch. I always tighten these cables wait 5 minutes then usually get a quarter to half turn on the connection as copper gives.
It could have been a lot worse......thanks for showing this. Not sure you have enough cable to put a larger extender box with a DIN rail with extensions below to the CU. If not then wago boxes but just check they match the cable temp and humidity rating in which they are going to be contained in.
I'm a electrician as well and there should not be any hidden joint boxes especially above the consumer unit the cables should be replaced to the isolator switches mains to the light circuit and both legs of a ring circuit and if there is a radial circuit the first leg of that should be replaced and any fused isolator switches from the board should be replaced cables for extensions or a garage should have a isolator switch on it and the main cables should be replaced from the isolator to the board as hidden joint boxes especially when the board is getting replaced you shouldn't by the bs7671 iee wiring regs place joint boxes on the cables coming into the main board so the first parts of the circuit have to be replaced to the board to keep the installation safe like!!
It is probably the shower unit - it has the most fire damage so it was burning for longer. (I am a registered research chemist and have fire investigation experience) Contact me if you want verification and free advice on electrical fire investigation.
Maybe people should start seriously considering having their electrics checked every so often, and not only if you're renting, a lot of people have some very old wiring in their properties, when saying that it doesn't necessarily mean it's unsafe but most likely is.
I have probably done or worked on hundreds of properties over my career which started in the late 80's, and I could probably count on one hand the amount of people that have called me after 5 years to say their installation is out of date and should be tested.
And the cut-outs,they seem to be over looked,the one here I got replaced was in a poor state,yet place had only been rewired about 12 years earlier.And some years ago while on holiday in Scotland,got shown a cottage being renovated & it that still had a Fused Neutral Cut-Out in use😲,contacted DNO about it & they replace it same day.
and thats why in North America, we never made our consumer units out of plastic and never had electric shower units.... its amazing the whole house didn't go up... someone must have been home at the time.... what a mess....
@@Hammy135 I only ask because if it were your place i was going to ask if you had noticed a burning small in the days, weeks, months leading up to the fire. Same thing happened in my place you see just without the fire, i kept smelling an electrical burning smell, not only was the screw loose to my shower MCB but also my Henley fuse (main fuse) was making poor contact & arching inside.
Worse fears realised. I'm the sort of person that always has to double check the back door even though I know I've locked it. Likewise with consumer units, I have often taken the cover off again to check terminals even though I know I did it. This would be the stuff of nightmares for me. That's why at 55 I'm giving it up. I don't wish to trivialise PTSD but this job has given me PTSD. Rarely do I sleep through a night without a dream about something like this waking me up. It seems to have got worse with age. Looking at this won't help. My brother in law is a painter and decorator. Works for himself and earns very good money. Sleeps like a log as well. Paint brushes her I come.
Sad truth is you're the kinda individual we need in this role, so it'd be a loss to loose you. Ultimately rechecking work only consumed your time, how many nested issues are there out there gone unchecked.
A big part of the problem has to be poor UK regulations. Here in Australia switch gear like that has to be in a metal fireproof enclosure which we call the 'power box' (inside of which is the plastic switch boxes), and every cable entry is sealed with flame retardant, so any fire from a bad joint self extinguishes, usually without even burning more than a few inches of cable from the switch device. Seeing the way you do things where a plastic power box with clear air gaps, can just sit on a flammable wall... its just crazy really. I wonder if UK has more house fires than AUS? Not to mention that appliance installers and plumbers would not be allowed install new switch gear.
@@sectokia1909 Our regs in the UK were updated a few years ago (took them long enough!!) so that metal consumer units are mandatory, plastic ones are no longer allowed for new installations.
I am 74 and I certainly understand this, it is because you care I work on Auto electrics and the fact that I might be responsible for death injury of people does give me nightmares. My saying after many years in the electrical trades "Nothing is trivial or Obvious"
I’ve seen a house fire take out a gas boiler, totally destroyed them (there were two) but the gas never leaked or added to the blaze. All gas connections are brass, no plastic & no gaskets or seals that can melt.
I ripped out a Square D board from an office during the summer with heat damage from a loose neutral... The only saving grace there was that it happened while people were still in (middle of the day on a Friday); a few hours later, it would have been empty over the weekend and gone unnoticed.
Root cause is loose connection which was complicated by 10mm incoming t+e. I think the only logical way this can have happened is if the loose incoming connection caused the wire to heat and melt the insulation. Then the incoming positive melted and touched the neutral. A 60a main fuse will carry an over current and arcing for a reasonable length of time. As the 10mm t+e incoming to the shower board was only protected by the supply fuse it should have been 16mm. If they had then shorted it would have carried a higher current and blown the main fuse quicker and heated less.
A couple of years ago we smelt something like burning polystyrene by the consumer unit cupboard next to the front door. Someone had forgot to tighten the terminal for the cooker circuit where it goes into the neutral bar. The plastic of the consumer unit housing had melted away from the bar leaving is suspended in air on the wires... So much for regulations insisting on fire doors if the consumer unit is fitted in the escape route, which is common.
Aren't there experts and investigators from the fire department or the insurance companies, who have expertise in fire investigation? Or is your investigation just out of interest of the client? No hate! I've just never heard of electrical installation companies doing professional investigation. ;)
Yeah buddy every fire service in the UK will have a fire investigator Ias would most insurance companies Cory said the electricity supplier and Distribution network operator asked him to investigate any cause of the issue and rectify them where needed I believe hope this is helpful mate stay safe
The energy supplier asked us to provide an investigation and report as the initial thoughts were that the smart meter was to blame because it was recently fitted.
They often ask sparks to go do an investigation as 1st gen smart meters were notorious for going up in flames after being fitted due to honestly not being fit for purpose as they couldn't handle the load. Also it's basically a half day course for smart meters, lost track of the sites I've attended where they've fitted smart E7 meters and shoved the switch neutral into the data port of the meter done it up, not checked the termination and left. Smart meters by intention are great but the fines the gov issues means the lads are permanently rushing job to job so the quality of the work isn't always the best from my experience.
@@effervescence5664jesus.. that's crazy I assumed they had to be competent qualified electricians it frightens.me that baboons like that can pull the main fuse but yet when it comes to a spark such as Jordan or cory doing it theyd get their knuckles wrapped yet the electricians have several years experience rather then half a days experience etc . Tbat was educational effer thanks
@@artisanelectrics Thank you for your reply! As I said: This was not meant to be an offense. I was just wondering, because in western europe, there will be an official investigation by an expert for every fire and I just didn't know that companies like suppliers ask sparks for investigations. ;)
A neighbour called me around after a new kitchen install since the mcb for the kitchen would not reset that evening. The re-tiling adhesive and grout had got into the boxes of three power outlets...simples...unscrew all outlets, clear out wet gunk and let dry out overnight. Next afternoon all good... screwed them back in...mcb happy again. Oh, hang on...where did the new under cupboard lights get wired in? Flex onto the back of the cooker!!! No she said...leave it...they are the professionals, they know what they’re doing!!! Words fail me.
The fire was external to the CU. And part of the plastic CU that was in close proximity to the isolator has melted. A metal CU would not have melted. It's as simple as that.
This seems to be happening more regularly. Worked as a spark for 40 years and never saw a consumer unit fire. Is this a result of bigger shower circuits? Will this happen more with the addition of EV chargers?
@@chrishutton1458Fires can happen anywhere, but I think they are mainly in very old installs. In the US, as long as no changes are made to an install and it met code at the time, it is grandfathered in and can stay as is, even if it's not up to current standards. I haven't owned an older home, so I don't know whether there may be other requirements from insurance carriers or others, but that is how it works in terms of meeting code. The current isn't really double at the high end, as the max power draw is lower. Most 120v circuits will be 18amp max 15amp continuous. There is a separate plug (that is compatible with the standard 3 prong) and spec for 20amp that is used basically for built-in microwaves in a residential context. For 240v circuits (stoves and dryers mostly), the breaker is often 30 or 50amps, but the wire and plug are massive and can certainly take that current.
I have mainly worked on modern auto electrical systems where I get vehicles that the dealer has not been able to fix, these are nearly all love jobs. The bane of my life in any electrical system is CONTACT RESISTANCE between two metals. When you to supply high currents through any junction point the tightness pressure is absolutely critical. Because metals have a positive temp coefficient of resistivity you can be easily misled as to the contact resistance when you have nice clean wires and contacts at the start pf a lose connection. When high currents go through a junction point the temp increases thus the contact resistance goes up. The current will hardly change. Thus the heating effect Current squared times contact resistance increases, thus the temperature at that junction point rises which then increases the contact resistance. You are now in a loop oxidation of the metal may start increasing the contact resistance even further. It is only a matter of time when the heat produces high temperatures melting any plastic or even high temperature insulation and of course the circuit breaker is still happily supplying the rated 50 amps. I know they are expensive but high quality thermal imaging cameras may now be an essential tool in any electrical work, I notice at Artisan Electrics you certainly fork out a lot of money on really good tools. I think a thermal test at full load using a thermal camera will really help seeing this burnt out consumer unit frightens the hell out of me. By the way this branch of Physical Chemistry which studies surface effects has only been recently better understood.
A few years back we discovered due to the smell and shortly after loss of power that when the house was built 25+ years before, the installing electrician had not tightened the screws holding the cable into the master switch on the consumer unit. it had over that time been arcing, probably from anyone coming down the stair as that would have passed enough vibration maybe. so it had been a ticking timebomb in the cupboard. we and previous owner were lucky
Haven’t been involved in fire investigation before and it’s a great video. I’m just thinking could the heating and cooling in a fire cause the loosening of the terminal
We had a small fire on our hot water circuit a couple years ago, been meaning to have the house rewired and the fuse board replaced with a modern circuit breaker/RCD setup. Trouble is some of the cables have older rubber insulation i think the electrician said, so those wires will need to be replaced
Well bite the bullet and get it done. Rubber perishes with time. I've seen bare wires with bits of old rubber hanging off them. How much do you value your life? Or your home?
I think you're absolutely right. I worked as an electrical assistant to a fire investigator for an insurance company in 1983. I've done a few of these jobs. It's very creepy, especially when it's winter and the bricks are still warm! That smell will stay with you for life. I repaired a main switch room fire feeding an industrial estate. I started on Monday morning after the call out and worked 24 hours a day until Thursday without any sleep so power could go back on and everyone could go back to work. Great video guys. Well done! It's a good neat tidy job you guys do. Good luck in the future!
I just sold my Florida house and had to pay for a breaker panel replacement. A 1993 Challenger panel (the size of a suitcase) because of a manufacturing bus bar fault, only cost me $2500 in the land of the free!
I think the smart meter you found melted started the fire. The way the firmen explained it, it was like a blow torch from the wooden board your mate said it was fitted on.
If you're an electrician every time the installation is tested or any work is done in the fuse board or isolators if you are good and have experience of installations you should check the connections Everytime it is tested or any additions or circuits have been added when you are checking the main board or isolators or especially rcds outside the board !!!!
Brilliant design on such an old board dating back about 50 or 60 years and they had chunky brass fittings. Shame newer boards don't have that design,I am sure that consumer unit fires would be quite rare if they went back to 2 screws per terminal
Another great video guys :) made my weekend seeing the artisan crew .been recovering from covid and this has made my day watching you two . Such an informative video as always Stay safe guys and keep it up . Hopw you all had a good new years and let's hope this year is better for us all
I know this is an old video now, but please make sure you report all such fires to your local Fire and Rescue Service even if they have been extinguished and everyone is safe. The FRS will investigate and make an entry on the national incident database. These statistics are vital evidence for deciding how to target educational fire safety campaigns and things like product recalls of unsafe products.
A pet hate of mine is a db fed from another db . To me it shows a lack of knowledge by the sparks or a lazy sparks .How long does take to fit henley blocks , earthing block , proper tails and a earth cable . If you don't have the proper tools or materials don't do the job
The other thing thats concerning is the fact that the sparks that installed a 50amp shower circuit of a 60 amp DNO main fuse with the rest of the house circuits. I would insist that main fuse was upgraded to a 100amp , if it couldn't be upgrade I would of told the customer that they needed a pumped shower that is fed from the hot and cold water tanks , that could them be fed from a socket , connect via a switch fused spur ,fitted with a ,3 amp fuse or I wouldn't do the job . My name goes on the certificate and I'm prepared to walk away from any job if I can't do it to a high standard or I can't advise the customer properly
Another problem is the inability of electricians to do load assessments. I suspect many of us think 'shower=10mm' with no consideration of what the actual rating of the appliance requires, nor the available capacity from a typical 60A supply. Terminating 10mm cables into MCBs and pull-switches requires an unusual amount of skill, patience and a bit of luck. Most of the time 6mm satisfies the requirements, and is less likely to result in events like this one.
See it all the time in large commercial installations - a board runs out of space so instead of replacing with a larger board (which would be neater), stick a second smaller board next to the existing then take the supply from the liveside of isolator.
@@robertburrows6612 I totally agree with what you say, how many people look at the existing installation as a whole and make an assessment from there. There are quite a few bang-and-buck installers who bash things in as fast as possible, no detail or care for the immediate or greater job and are quite happy to charge; I also suspect some of these would take liberties that the customer wouldn’t know of their rights to a certificate, especially customers of an age where certification was unheard of.
At some point in the past the IET proposed that terminal tightness should be a maintenance check because copper has fluid characteristics and over time connections can become loose; as appears to have occurred here. I’m wondering why; other than the main fuse, the down stream protection did not disconnect the circuit? Maybe the heat energy of the ‘spark gap’ created was much less than that the mcb rating would have created. A salutary example of poor installations. Thanks for posting.
@@tomorichard it’s down to the judgement of the inspector, most would. This was most probably not a rental property, the irony being if it was, these faults would have been found, corrected and the CU replaced with metal, to name a few now obvious shortcomings, they weren’t seen as shortcomings when the original installation was done, how times have changed but for the good!
OOooOOHH My God! Wow how it happened when the fire started.. I think Shower heater had a problem.. I am not sure. what is it cause start from. Great job team! Thumb up! Cheer!
I tend to disagree with source of fire. Charring on rafter above plasterboard seems to indicate seat of initial fault was there, due to charring extent there has been extended period of thermal activity. It looks like a circuit cable from main DB was looped under 10mm going to shower, as shower board looks to be later addition my bet is as follows. 10mm to shower has been initially drawn up from cable reel on floor during installation, this has rubbed through insulation of previously installed cable above plasterboard (damage would not been seen as in tight corner of loft space). Arcing has developed in original cable, leading to further arcing/heat transfer into 10mm shower cable, this has led to insulation damage in shower board. This has the led to further arcing in shower board, with catastrophic damage to shower board. Arcing would then melt the conductor as seen, I’d doubt tight conductor bend alone would cause sufficient conductor damage to initiate fault
If it was possible, a check would have been needed to see if the multistrand conductor was "twisted" in the RCBO clamp terminal. Multistrand (7 strand) should be inserted, as stripped into clamp terminations, so the strands spread out during tightening, you only twist 3-7 strand conductors if they are going into a barrel terminal with a direct acting screw.
Interesting investigation. In terms of the masks, I think you'd be better with FFP3 masks in that situation. Those masks only stop direct penetration whereas FFP3 masks also stop dust and ash from infiltrating through the gaps in the sides and stops smaller more dangerous particles getting into the lungs.
I am not if there are any rules re this (im not a spark) but I would have thought it was a good idea to never have electrical wires running near boilers or gas lines unless they are run within metal/fireproof conduit, metal boards help but not when the fire starts behind walls etc. I know in Portugal many modern flats have gas/water cutoff valves outside the flat that are wired back to the fire/flood detectors and cut them off, in my dads place there is water sensor in the kitchen/bathrooms, ofcourse its a tiled floor on concrete slab. Im thinking with all the smart gas meters out there could be an easy way for them having the ability to be paired to fire detectors (not smoke or if smoke then time delayed) then turn off, this would not need the addition of extra valves.
Quite an interesting video. Was the theory on the sharp bends in the wires have any relevance though? And if not this situation, have you had any similar where it could be easier and/or cheaper to just replace the whole cable? because I can imagine some shorter and easy route runs, rather than testing, it'd be quicker to just replace? Can't wait for Big Clive's investigation too, although that said, you've probably nailed the main conclusion!
I think now i can recall my caravan fuse board had this same thing where the onboard charger unit was connected straight off the tails input, so this was not fused, although the main power supply probably limited is limited to 10amps or something, i didn't think this was good practice from whoever wired this.
If you are correct in your diagnosis there would have been a very strong smell every time the shower was in use, over heating cable gives off a very strong unmistakable smell that lingers, the shower itself would have also have been showing signs of the issue in either poor heating performance & or the water solenoid blipping off whilst the shower was running. Also an overheating cable will leave a screw in an mcb or rcd loose, the cable expands with heat & changes shape to a more compact form.
I caught the switch show RCD VR63 63Amp 30mA 230V. I see that the Main fuse (Black box) shows 60Amp. Can you check Shower box for how many amps? Thumb up!! Cheer!
The only time I have come across a fuse board fire was to a volex board. There was a recall on volex breakers several years ago, they also made newlec boards for newey and eyre.
@@artisanelectrics yeah, usually when I find loose connections it has always been the neutrals that were loose and the lives were very tight, i think some people don't understand (worryingly) that the neutral is carrying the same current or they don't think the neutral is as dangerous as the live so they don't treat it with the same respect which makes no sense to me.
bodge job would be my guess with an exposed wire somewhere and likely to many things off of 1 circuit I would say a combination wire age and arcing on metal .. guessing townhouse with a mix of power additions since the 1940's-1960's (built by) to current day likely needed a complete gut 10-20 years ago .. either faulty install of replacement fuse box or faulty install additional fuse box with combination of an over loaded and over current currant circuit .. over amperage contribution to the actual fire.. this why I have always said every 20-25 years you should budget for wiring replacement it pays not to comply date of install as a precursor to do nothing.. because safety codes of the day should always supersede date of install.. To be honest I am surprised there isn't more electrical house fires in the UK given bodge work by both home owners and electrical tradies.
I often see tails on the supply side that with a bit of a wriggle do come loose. I always tighten AND THEN wriggle and twist 16 & 25mm tails and i always get a further turn on the screw.
I want to say, after seeing two loose-connection consumer unit fires recently... Use RCBOs. Everywhere. I have encountered multiple installations over here, with bad connections on breakers. They get hot, the conductors are damaged, but the heat on the terminal tends to travel up inside the breaker and the thermal element most often trips before there's a fire.
@Lister Smeg Not specifically by design, and it's not something to always rely on - but yes, only because the heat produced by a loose connection will also heat the internal parts of the breaker, including the thermal trip element, which is exists in an RCBO but not in a plain RCD.
Must have been loads of flickering lights when that shorted. Even other houses would have noticed. Same phase houses would have gone dimmer and other phase houses would have gone brighter.
Tool of the day:
Armeg Torque Screwdriver Set: amzn.to/39i4ifW
Love the tool of the day being a torque screwdriver set :)
Torque screwdriver set 19pcs draper made in uk did you have on or can make a video for torque screwdriver draper?????
Can someone tell what screws are used in Triton terminal blocks? They look like plusminus PH/Slotted
I wonder if they completely forgot to tighten the screw, stuffed the wire down the back of the clamp or just didn't recheck after the cable had been manipulated. I was a sceptic about the torque screwdrivers until I found out that kitchen fitters are using their cordless impact drivers to tighten screws in breakers because they're...... Joiners. That's resulting in stripped screws (WTF?) and over torqued terminals that still instantly loosened when the cable is moved. Part-P is a terrible thing.
Technically speaking the electrical regulations don't actually require a shower isolator, but it's encouraged by the shower manufacturers so their electro-labourers can swap bits under warranty without understanding complicated things like distribution boards (meow!). There's a good chance the isolator was grudgingly installed because the breaker was out of reach.
Did you ever do a video on this one? Took a quick look but couldn't find it if you have.
@@Jason-ko2tb
I would LOVE to see Big Clive do a tear down on this 👍🏻
I had my electric shower re-routed so to speak. It was tripping my RCD
Essentially the person before me was an auto electrician and connected the electric shower on the same circuit as some mains and decided to connect it with a bit of solder which is just fantastic /s
He's qualified to be an auto electrician but not for regular electrics
I'm glad it tripped in a way, because £200 for a fix is better than a fire which costs a lot more in both money and lives.
I'll be swapping it out for a mixer shower nonetheless. This is also why you absolutely should get proper sparkies out who know what they're doing.
Or indeed for anything else for that matter. Properly qualified people means that a job is done better
Very interesting video ! I was a fire investigator for the police, and these electrical fires are always fascinating. By the way, as an ex fireman I'd advise you to wear an FFP3 mask, especially where MMMF debris can occur.
Thanks a lot
And full gloves, you cannot predict what compounds are contained in the burnt plastics.
I wondered what was going on with the surgical mask which is bloody useless for stopping breathing anything in.
Maybe they could do with some mask and face fit training.
@@eddwalch-homecraftproperty6613 Yeah, I was thinking the same. Gloves like that, are so stupid.
In this case he could as well do without gloves, because most of the contact with all that soot and burned plastic, is happening right at the parts that's not covered (the finger tips). Even for normal work, they give very little electrical protection (fingertips are most likely to make contact with something live first), very little protection to other forms of dirt or oil/grease as well (for example when working on cars) and isn't great for cold weather either. They are really just made for pussies who think heavy work and lifting stuff, hurt their hands
I think the surgical mask was a COVID thing, this video is over 2 years old.
This is a good video for DIYers so they understand how important it is to do everything 100% correct and get it checked by qualified electrician with right tools at the end. The fact it works doesn't mean it's safe.
Just invested in a torque screwdriver! Looks like good experience / eye opener for your apprentice! Just shows how easily something can go wrong months/years down the line
Few years ago new neighbour got locked out, so when i was getting her in asked her why she had moved, she said she had a fire in the fuse box and almost burnt her house out, so was downsizing, googled fuse box fires and they seem to happen quite often, so fitted a smoke alarm inside the fuse box housing cabinet above the front door. and one below it as well to be sure.
Also a while ago taking to an electrical engineer who said that the new smart meters are liable to catch fire as so much power going through such a small box will cause problems.
Finally even though the power is disconected and fuse removed it still gives me the shivers, seeing you both with fingers in the maze of cables, from when i pushed a Mecanno screwdriver into a 240 set of christmas tree lights, still have that fear of electric now and the huge bang and shock.
Mecanno screwdrivers could fix anything when youre niave or just thick..
Very interesting to see the consequences of one loose screw on a high-current circuit. I can see that the 50A breaker didn't trip because the short circuit was on the supply side. I worry a little (as someone who designs EV charge points for a living) that we'll see more of this sort of thing with poorly installed EV chargers. Very few domestic circuits run at full capacity for hours on end, but an EV charger certainly will. Even 32A could get a loose terminal pretty toasty.
Many meters are in a cabinet on an external wall of the house. I wonder; perhaps splitting the supply off just after the meter (before the consumer unit) and passing the charge point feed through a weatherproof breaker (box) on house exterior would be best? The idea being that any fire would be on the exterior of the house.
@@simongreenidge6454 I guess there's no reason why not, if the layout of the property allows it. Wouldn't work in many properties, like mine in Cambridge, though: the DNO's cutout, meter and consumer unit are all together under the stairs.
Ye spot on especially with a load like that
This is why having a big contactor in the electrical cabinets controlled by a Thermal (HTC) Switch. It will cut off if the cabinet begin to heat too much (before a fire).
Also it is good to check the screws once a year.
Or manufacturers could transition to spring/lever terminals instead, 32A is perfectly doable and much more reliable in terms of install quality and longevity.
Heard a story from a friend where he went to a new build job to fault find, the lights in the whole house were flashing every time someone closed the front door or jumped up and down inside the house. Turns out the busbar wasn’t in properly 😬
Wow
😳
Should've sent the entire piece of wall to clive.
My fuseboard fire was better 👀👀 good job though guys 👍
I recon Jordan set this up to catch fire so he could try and get better fire damage content than yours. 😂
😆
NO FUSE BOARD FIRE IS BETTER BOYS
@@bigissue9179 it was just in jest. We know how competitive the electricians can get. 😂
lol
I'm always shocked at the random placement of electrical main fuses and boards in the UK.
Yeah it's crazy, these dudes over there have no idea what in the actual F they're doing.
Damn...that was a pretty nasty burn from a loose connection!
I always recheck each screw as the last thing I do before closing up the box (CU) when finishing up.
You can see the fire started just below the rafter that has the initial burning and charring on it in the ceiling, so what ever is just below that was the cause of the fire.
I like what you said about the shower isolator being near the electric meter. Mine is a similar setup with the main circuit breaker in the meter cupboard however the isolator switch is on the wall in my hallway obviously going through the wall into the back of the shower unit. Interestingly it’s a big red switch much like a cooker switch too
I truly believe one of the most important aspects of being an electrician is tight connections.
Those solid stranded conductors always need a good wiggle and retightening - the installer forgot, didn't know, or didn't care. Tapping off the main incomer tells you a lot about the "installer".
2.45 "customers wants me to get the power back on tonight" are they having a laugh 😂. First world problems right there
Maybe they could get a couple of coats of paint on too before they left 😂
Whilst your here could you change out some downlights for me? 😂
Yeah 😂
I guess they want some heating back which is the first emergency to restore.
But yeah...
@@YouRich92 Fair point but I'd be mentioning that the boiler needs checking before switching back on, especially what looks like a melted filter... But I suppose electric heating is an alternative!
As a old Sparky, I could never understand why the terminals went to one screw instead of the two we used to have. But hey whats a fire between production costs and they have only just gone back to all steel boards, well I never!. A wet string job as we used to say. 6mm backed by a 60/100a supply fuse- electrician? Toast any one. Good job this guy didn't work on commercial.
Glad no one was injured !
Many years ago got called out to a badly fire damaged garage with a bedroom above. The person was asleep in the bedroom at the time and room was filling with smoke. It was noticed by other family members who smelt burning and quickly got the person out of bed to safety.
It was a really easy diagnosis of fault. A gas pipe in the garage had a small pin prick allowing gas to escape and directly above was a time switch which switched on at midnight. The small spark from timeswitch ignited gas and it acted as a blow torch straight on to ceiling of garage.
Definitely the shower board for point of origin. Looks like the live incomer and neutral shorted and took out the main fuse. Looks of new plaster board and paintwork needed so may as well take down the ceiling to check the cable above. Always a fun job lads.
For all the yanks like myself watching: 10mm^2 cable is AWG8, 6mm^2 is AWG10.
The plastic consumer units always gave me the creeps. I'm happy to hear about the metal enclosure mandate.
6mm2 is not usually sufficient for a load of up to 50A. European 10 mm2 wiring or American AWG8 (8.4 mm2) would be sufficient for a 10kW shower heater.
Agreed. My shower is on 6mm but is only 35.5A. The electrician allowed it because the cable is only 16m and he said the voltage drop would be acceptable. But he did insist on running it on a 32A breaker, so it's on the border 6242B cable, which has a slightly higher melting point than 6242Y (pvc) cable. 10mm would have been better even for my 8.5kW shower.
I have lost count on the amount of slack connections in a consumer unit and shower switch. I always tighten these cables wait 5 minutes then usually get a quarter to half turn on the connection as copper gives.
Well at least Oscar can see what happens when you don't tighten up the connections tight 👍
It could have been a lot worse......thanks for showing this. Not sure you have enough cable to put a larger extender box with a DIN rail with extensions below to the CU. If not then wago boxes but just check they match the cable temp and humidity rating in which they are going to be contained in.
I'm a electrician as well and there should not be any hidden joint boxes especially above the consumer unit the cables should be replaced to the isolator switches mains to the light circuit and both legs of a ring circuit and if there is a radial circuit the first leg of that should be replaced and any fused isolator switches from the board should be replaced cables for extensions or a garage should have a isolator switch on it and the main cables should be replaced from the isolator to the board as hidden joint boxes especially when the board is getting replaced you shouldn't by the bs7671 iee wiring regs place joint boxes on the cables coming into the main board so the first parts of the circuit have to be replaced to the board to keep the installation safe like!!
It is probably the shower unit - it has the most fire damage so it was burning for longer. (I am a registered research chemist and have fire investigation experience) Contact me if you want verification and free advice on electrical fire investigation.
Maybe people should start seriously considering having their electrics checked every so often, and not only if you're renting, a lot of people have some very old wiring in their properties, when saying that it doesn't necessarily mean it's unsafe but most likely is.
No shit, I haven’t taken mine apart at home properly and this video makes me nervous as hell. I think I might bring forward my board change 😳
I have probably done or worked on hundreds of properties over my career which started in the late 80's, and I could probably count on one hand the amount of people that have called me after 5 years to say their installation is out of date and should be tested.
And the cut-outs,they seem to be over looked,the one here I got replaced was in a poor state,yet place had only been rewired about 12 years earlier.And some years ago while on holiday in Scotland,got shown a cottage being renovated & it that still had a Fused Neutral Cut-Out in use😲,contacted DNO about it & they replace it same day.
and thats why in North America, we never made our consumer units out of plastic and never had electric shower units.... its amazing the whole house didn't go up... someone must have been home at the time.... what a mess....
Was the shower in use when the fire started?
You bet
@@Hammy135 you were there ? Your house / home ?
@@WhiskeyGulf71 nah, I don’t know. It’ll arc more under load though so it would make sense
@@Hammy135
I only ask because if it were your place i was going to ask if you had noticed a burning small in the days, weeks, months leading up to the fire.
Same thing happened in my place you see just without the fire, i kept smelling an electrical burning smell, not only was the screw loose to my shower MCB but also my Henley fuse (main fuse) was making poor contact & arching inside.
Worse fears realised. I'm the sort of person that always has to double check the back door even though I know I've locked it. Likewise with consumer units, I have often taken the cover off again to check terminals even though I know I did it. This would be the stuff of nightmares for me. That's why at 55 I'm giving it up. I don't wish to trivialise PTSD but this job has given me PTSD. Rarely do I sleep through a night without a dream about something like this waking me up. It seems to have got worse with age. Looking at this won't help. My brother in law is a painter and decorator. Works for himself and earns very good money. Sleeps like a log as well. Paint brushes her I come.
Sad truth is you're the kinda individual we need in this role, so it'd be a loss to loose you. Ultimately rechecking work only consumed your time, how many nested issues are there out there gone unchecked.
A big part of the problem has to be poor UK regulations. Here in Australia switch gear like that has to be in a metal fireproof enclosure which we call the 'power box' (inside of which is the plastic switch boxes), and every cable entry is sealed with flame retardant, so any fire from a bad joint self extinguishes, usually without even burning more than a few inches of cable from the switch device. Seeing the way you do things where a plastic power box with clear air gaps, can just sit on a flammable wall... its just crazy really. I wonder if UK has more house fires than AUS? Not to mention that appliance installers and plumbers would not be allowed install new switch gear.
@@sectokia1909 Our regs in the UK were updated a few years ago (took them long enough!!) so that metal consumer units are mandatory, plastic ones are no longer allowed for new installations.
I am 74 and I certainly understand this, it is because you care I work on Auto electrics and the fact that I might be responsible for death injury of people does give me nightmares. My saying after many years in the electrical trades "Nothing is trivial or Obvious"
I was going to ask if you were sending it to Big Clive, I look forward to his video too.
Good job it never spread to the gas. That could of gone a lot worse
I’ve seen a house fire take out a gas boiler, totally destroyed them (there were two) but the gas never leaked or added to the blaze. All gas connections are brass, no plastic & no gaskets or seals that can melt.
I ripped out a Square D board from an office during the summer with heat damage from a loose neutral...
The only saving grace there was that it happened while people were still in (middle of the day on a Friday); a few hours later, it would have been empty over the weekend and gone unnoticed.
This is scary. They talk about the importance of making sure connections are not loose. Now I see why !
Root cause is loose connection which was complicated by 10mm incoming t+e.
I think the only logical way this can have happened is if the loose incoming connection caused the wire to heat and melt the insulation. Then the incoming positive melted and touched the neutral.
A 60a main fuse will carry an over current and arcing for a reasonable length of time.
As the 10mm t+e incoming to the shower board was only protected by the supply fuse it should have been 16mm. If they had then shorted it would have carried a higher current and blown the main fuse quicker and heated less.
You are bang on sir,
But what caused the heat? Current in the cable or arcing?
“Maybe we’ll cut it out and send it to Big Clive” haha
A couple of years ago we smelt something like burning polystyrene by the consumer unit cupboard next to the front door. Someone had forgot to tighten the terminal for the cooker circuit where it goes into the neutral bar. The plastic of the consumer unit housing had melted away from the bar leaving is suspended in air on the wires... So much for regulations insisting on fire doors if the consumer unit is fitted in the escape route, which is common.
Aren't there experts and investigators from the fire department or the insurance companies, who have expertise in fire investigation? Or is your investigation just out of interest of the client?
No hate! I've just never heard of electrical installation companies doing professional investigation. ;)
Yeah buddy every fire service in the UK will have a fire investigator Ias would most insurance companies Cory said the electricity supplier and Distribution network operator asked him to investigate any cause of the issue and rectify them where needed I believe hope this is helpful mate stay safe
The energy supplier asked us to provide an investigation and report as the initial thoughts were that the smart meter was to blame because it was recently fitted.
They often ask sparks to go do an investigation as 1st gen smart meters were notorious for going up in flames after being fitted due to honestly not being fit for purpose as they couldn't handle the load. Also it's basically a half day course for smart meters, lost track of the sites I've attended where they've fitted smart E7 meters and shoved the switch neutral into the data port of the meter done it up, not checked the termination and left. Smart meters by intention are great but the fines the gov issues means the lads are permanently rushing job to job so the quality of the work isn't always the best from my experience.
@@effervescence5664jesus.. that's crazy I assumed they had to be competent qualified electricians it frightens.me that baboons like that can pull the main fuse but yet when it comes to a spark such as Jordan or cory doing it theyd get their knuckles wrapped yet the electricians have several years experience rather then half a days experience etc . Tbat was educational effer thanks
@@artisanelectrics Thank you for your reply! As I said: This was not meant to be an offense. I was just wondering, because in western europe, there will be an official investigation by an expert for every fire and I just didn't know that companies like suppliers ask sparks for investigations. ;)
Yes send it to big Clive look forward to seeing that.😎
A neighbour called me around after a new kitchen install since the mcb for the kitchen would not reset that evening. The re-tiling adhesive and grout had got into the boxes of three power outlets...simples...unscrew all outlets, clear out wet gunk and let dry out overnight. Next afternoon all good... screwed them back in...mcb happy again. Oh, hang on...where did the new under cupboard lights get wired in? Flex onto the back of the cooker!!! No she said...leave it...they are the professionals, they know what they’re doing!!! Words fail me.
Might as well tear down the whole ceiling in that room as the old plasterboard will trap the burning odor.
I thought the same
Definitely, pull it down, that way you will see everything.
Would be interesting to see exactly the same set up and the result from metal 18th edition board as to how much the metal enclosure helps
The fire was external to the CU.
And part of the plastic CU that was in close proximity to the isolator has melted.
A metal CU would not have melted.
It's as simple as that.
Just shows you what a loose connection can do 😳
This seems to be happening more regularly. Worked as a spark for 40 years and never saw a consumer unit fire. Is this a result of bigger shower circuits? Will this happen more with the addition of EV chargers?
Yeah heavy loads are more susceptible to fire
It's the result of poor workmanship more than anything else.
@@Monkeh616 yup definately the workmanship
@@artisanelectrics Does America suffer with lots of electrical fires? Half the voltage, Double the current, 4x the heating (I squared R)
@@chrishutton1458Fires can happen anywhere, but I think they are mainly in very old installs. In the US, as long as no changes are made to an install and it met code at the time, it is grandfathered in and can stay as is, even if it's not up to current standards. I haven't owned an older home, so I don't know whether there may be other requirements from insurance carriers or others, but that is how it works in terms of meeting code.
The current isn't really double at the high end, as the max power draw is lower. Most 120v circuits will be 18amp max 15amp continuous. There is a separate plug (that is compatible with the standard 3 prong) and spec for 20amp that is used basically for built-in microwaves in a residential context.
For 240v circuits (stoves and dryers mostly), the breaker is often 30 or 50amps, but the wire and plug are massive and can certainly take that current.
I have mainly worked on modern auto electrical systems where I get vehicles that the dealer has not been able to fix, these are nearly all love jobs. The bane of my life in any electrical system is CONTACT RESISTANCE between two metals. When you to supply high currents through any junction point the tightness pressure is absolutely critical. Because metals have a positive temp coefficient of resistivity you can be easily misled as to the contact resistance when you have nice clean wires and contacts at the start pf a lose connection. When high currents go through a junction point the temp increases thus the contact resistance goes up. The current will hardly change. Thus the heating effect Current squared times contact resistance increases, thus the temperature at that junction point rises which then increases the contact resistance. You are now in a loop oxidation of the metal may start increasing the contact resistance even further.
It is only a matter of time when the heat produces high temperatures melting any plastic or even high temperature insulation and of course the circuit breaker is still happily supplying the rated 50 amps.
I know they are expensive but high quality thermal imaging cameras may now be an essential tool in any electrical work, I notice at Artisan Electrics you certainly fork out a lot of money on really good tools. I think a thermal test at full load using a thermal camera will really help seeing this burnt out consumer unit frightens the hell out of me.
By the way this branch of Physical Chemistry which studies surface effects has only been recently better understood.
A few years back we discovered due to the smell and shortly after loss of power that when the house was built 25+ years before, the installing electrician had not tightened the screws holding the cable into the master switch on the consumer unit. it had over that time been arcing, probably from anyone coming down the stair as that would have passed enough vibration maybe. so it had been a ticking timebomb in the cupboard. we and previous owner were lucky
I've joined because of a Big Clive video. Like your vid and your editing style. I'm from the US but I like to see other countries electric systems.
Haven’t been involved in fire investigation before and it’s a great video. I’m just thinking could the heating and cooling in a fire cause the loosening of the terminal
Electrical fire - a real nightmare, thank goodness for fuses 😃👌👏👏👏❤️
We had a small fire on our hot water circuit a couple years ago, been meaning to have the house rewired and the fuse board replaced with a modern circuit breaker/RCD setup. Trouble is some of the cables have older rubber insulation i think the electrician said, so those wires will need to be replaced
Well bite the bullet and get it done.
Rubber perishes with time. I've seen bare wires with bits of old rubber hanging off them.
How much do you value your life?
Or your home?
I think you're absolutely right. I worked as an electrical assistant to a fire investigator for an insurance company in 1983.
I've done a few of these jobs. It's very creepy, especially when it's winter and the bricks are still warm! That smell will stay with you for life. I repaired a main switch room fire feeding an industrial estate. I started on Monday morning after the call out and worked 24 hours a day until Thursday without any sleep so power could go back on and everyone could go back to work. Great video guys. Well done! It's a good neat tidy job you guys do. Good luck in the future!
Well that was stupid wasn't it
So you worked 96 hours without any sleep?
Interesting and informative as ever.
I wonder if the customer would be interested in Arc Fault Detection in their shiny new consumer unit?🤔
You need to come to America and see the difference. You would find it quite interesting
@Lk M - can you elaborate please?
@@seventeesweremagic
No just 1930s technology.
I just sold my Florida house and had to pay for a breaker panel replacement. A 1993 Challenger panel (the size of a suitcase) because of a manufacturing bus bar fault, only cost me $2500 in the land of the free!
I think the smart meter you found melted started the fire. The way the firmen explained it, it was like a blow torch from the wooden board your mate said it was fitted on.
If you're an electrician every time the installation is tested or any work is done in the fuse board or isolators if you are good and have experience of installations you should check the connections Everytime it is tested or any additions or circuits have been added when you are checking the main board or isolators or especially rcds outside the board !!!!
Interesting thought, the old Wyler rewirables had 2 screws on the neutral and outgoing live. They never came lose!
Brilliant design on such an old board dating back about 50 or 60 years and they had chunky brass fittings. Shame newer boards don't have that design,I am sure that consumer unit fires would be quite rare if they went back to 2 screws per terminal
Another great video guys :) made my weekend seeing the artisan crew .been recovering from covid and this has made my day watching you two . Such an informative video as always Stay safe guys and keep it up . Hopw you all had a good new years and let's hope this year is better for us all
Thanks, hope you feel better soon!
Were you near death?
@@Woodkin007 pretty sick yeah mate . Thankfully the steroids helped
I know this is an old video now, but please make sure you report all such fires to your local Fire and Rescue Service even if they have been extinguished and everyone is safe. The FRS will investigate and make an entry on the national incident database. These statistics are vital evidence for deciding how to target educational fire safety campaigns and things like product recalls of unsafe products.
A pet hate of mine is a db fed from another db . To me it shows a lack of knowledge by the sparks or a lazy sparks .How long does take to fit henley blocks , earthing block , proper tails and a earth cable . If you don't have the proper tools or materials don't do the job
The other thing thats concerning is the fact that the sparks that installed a 50amp shower circuit of a 60 amp DNO main fuse with the rest of the house circuits. I would insist that main fuse was upgraded to a 100amp , if it couldn't be upgrade I would of told the customer that they needed a pumped shower that is fed from the hot and cold water tanks , that could them be fed from a socket , connect via a switch fused spur ,fitted with a ,3 amp fuse or I wouldn't do the job . My name goes on the certificate and I'm prepared to walk away from any job if I can't do it to a high standard or I can't advise the customer properly
Another problem is the inability of electricians to do load assessments. I suspect many of us think 'shower=10mm' with no consideration of what the actual rating of the appliance requires, nor the available capacity from a typical 60A supply. Terminating 10mm cables into MCBs and pull-switches requires an unusual amount of skill, patience and a bit of luck. Most of the time 6mm satisfies the requirements, and is less likely to result in events like this one.
@@westinthewest I completely agree with you. The signs were there this install of that shower circuit was heading for trouble
See it all the time in large commercial installations - a board runs out of space so instead of replacing with a larger board (which would be neater), stick a second smaller board next to the existing then take the supply from the liveside of isolator.
@@robertburrows6612 I totally agree with what you say, how many people look at the existing installation as a whole and make an assessment from there. There are quite a few bang-and-buck installers who bash things in as fast as possible, no detail or care for the immediate or greater job and are quite happy to charge; I also suspect some of these would take liberties that the customer wouldn’t know of their rights to a certificate, especially customers of an age where certification was unheard of.
At some point in the past the IET proposed that terminal tightness should be a maintenance check because copper has fluid characteristics and over time connections can become loose; as appears to have occurred here. I’m wondering why; other than the main fuse, the down stream protection did not disconnect the circuit? Maybe the heat energy of the ‘spark gap’ created was much less than that the mcb rating would have created. A salutary example of poor installations. Thanks for posting.
There was no downstream protection from the shower CU other than the main fuse..
@@Sparks0001 the main fuse is upstream
Judging by the amount of turns he got on the live terminal compared to the neutral I don't think it was done up tight in the first place
Is terminal tightness not a maintenance check in the form of a eicr?
@@tomorichard it’s down to the judgement of the inspector, most would. This was most probably not a rental property, the irony being if it was, these faults would have been found, corrected and the CU replaced with metal, to name a few now obvious shortcomings, they weren’t seen as shortcomings when the original installation was done, how times have changed but for the good!
Nice job. I hope I do a better job with my new consumer unit and RCBOs. Thanks for the help with the EV Ultra Jordan. 👍👍
OOooOOHH My God! Wow how it happened when the fire started.. I think Shower heater had a problem.. I am not sure. what is it cause start from. Great job team! Thumb up! Cheer!
I'm surprised the fire brigade didn't call the DNO
Possibly arcing from within the loose connection caused the insulation on the wire to melt/catch-fire ...
Yep
Nightmare! Thank God no-one was hurt. There wasn't anyone hurt was there?
No everyone was fine
I tend to disagree with source of fire. Charring on rafter above plasterboard seems to indicate seat of initial fault was there, due to charring extent there has been extended period of thermal activity. It looks like a circuit cable from main DB was looped under 10mm going to shower, as shower board looks to be later addition my bet is as follows. 10mm to shower has been initially drawn up from cable reel on floor during installation, this has rubbed through insulation of previously installed cable above plasterboard (damage would not been seen as in tight corner of loft space). Arcing has developed in original cable, leading to further arcing/heat transfer into 10mm shower cable, this has led to insulation damage in shower board. This has the led to further arcing in shower board, with catastrophic damage to shower board. Arcing would then melt the conductor as seen, I’d doubt tight conductor bend alone would cause sufficient conductor damage to initiate fault
It was a loose connection in the shower board as you will see
If it was possible, a check would have been needed to see if the multistrand conductor was "twisted" in the RCBO clamp terminal. Multistrand (7 strand) should be inserted, as stripped into clamp terminations, so the strands spread out during tightening, you only twist 3-7 strand conductors if they are going into a barrel terminal with a direct acting screw.
Interesting investigation. In terms of the masks, I think you'd be better with FFP3 masks in that situation. Those masks only stop direct penetration whereas FFP3 masks also stop dust and ash from infiltrating through the gaps in the sides and stops smaller more dangerous particles getting into the lungs.
Interesting video, can’t wait for part 2. Someone got a nice cleaning job on there hands.
Normally lose connections seen it on a 600a breaker quite spectacular
Who did the installation? Any come backs on the installer?
A 50 amp shower circuit plus a cooker: surely a 60 amp cutout is likely to blow with this loading?
I am not if there are any rules re this (im not a spark) but I would have thought it was a good idea to never have electrical wires running near boilers or gas lines unless they are run within metal/fireproof conduit, metal boards help but not when the fire starts behind walls etc. I know in Portugal many modern flats have gas/water cutoff valves outside the flat that are wired back to the fire/flood detectors and cut them off, in my dads place there is water sensor in the kitchen/bathrooms, ofcourse its a tiled floor on concrete slab.
Im thinking with all the smart gas meters out there could be an easy way for them having the ability to be paired to fire detectors (not smoke or if smoke then time delayed) then turn off, this would not need the addition of extra valves.
Quite an interesting video. Was the theory on the sharp bends in the wires have any relevance though? And if not this situation, have you had any similar where it could be easier and/or cheaper to just replace the whole cable? because I can imagine some shorter and easy route runs, rather than testing, it'd be quicker to just replace? Can't wait for Big Clive's investigation too, although that said, you've probably nailed the main conclusion!
Thanks!
I think now i can recall my caravan fuse board had this same thing where the onboard charger unit was connected straight off the tails input, so this was not fused, although the main power supply probably limited is limited to 10amps or something, i didn't think this was good practice from whoever wired this.
Looking forward to Big Clive's video :-)
If you are correct in your diagnosis there would have been a very strong smell every time the shower was in use, over heating cable gives off a very strong unmistakable smell that lingers, the shower itself would have also have been showing signs of the issue in either poor heating performance & or the water solenoid blipping off whilst the shower was running.
Also an overheating cable will leave a screw in an mcb or rcd loose, the cable expands with heat & changes shape to a more compact form.
Nice detective work, thanks for sharing.
I caught the switch show RCD VR63 63Amp 30mA 230V. I see that the Main fuse (Black box) shows 60Amp. Can you check Shower box for how many amps? Thumb up!! Cheer!
You can't judge if the MCB has tripped from the position of the lever, it will move internally even if you jam in the on position.
True
Holy shit, you think council/government would have their own fire investigation team, anyways good job putting on your detective hat on for that day 😑
Don’t domestic panels need a regular inspection or re-torque after a few days for new installations?
The only time I have come across a fuse board fire was to a volex board.
There was a recall on volex breakers several years ago, they also made newlec boards for newey and eyre.
Yeah it’s pretty bad
Loose live? It's usually the other way round i have always found the neutrals to be loose.
Interesting
@@artisanelectrics yeah, usually when I find loose connections it has always been the neutrals that were loose and the lives were very tight, i think some people don't understand (worryingly) that the neutral is carrying the same current or they don't think the neutral is as dangerous as the live so they don't treat it with the same respect which makes no sense to me.
Yeah the connection in a mcb is big clamp and neutral bar one screw never understood that
Maybe a dumb question but are jb’s the preferred method of extending cables.not through crimps.
Thermally cycling circuits aren't good in JBs, terminal screws become loose over time
I had a power cut once because an electrician didn't tighten the terminal on something it the meter box. Lucky there was no fire
bodge job would be my guess with an exposed wire somewhere and likely to many things off of 1 circuit I would say a combination wire age and arcing on metal ..
guessing townhouse with a mix of power additions since the 1940's-1960's (built by) to current day likely needed a complete gut 10-20 years ago ..
either faulty install of replacement fuse box or faulty install additional fuse box with combination of an over loaded and over current currant circuit ..
over amperage contribution to the actual fire..
this why I have always said every 20-25 years you should budget for wiring replacement it pays not to comply date of install as a precursor to do nothing.. because safety codes of the day should always supersede date of install..
To be honest I am surprised there isn't more electrical house fires in the UK given bodge work by both home owners and electrical tradies.
I often see tails on the supply side that with a bit of a wriggle do come loose. I always tighten AND THEN wriggle and twist 16 & 25mm tails and i always get a further turn on the screw.
Was the 10mm shower circuit protected by a Circuit Breaker at the consumer unit or just relying on the cut out fuse?
It's covered in the video. The shower circuit is wired directly into the main isolator switch, no breaker.
11:53 If the live and neutral was shorted on the 'incoming' eg, BEFORE the MCB, would it have triggered?
very lucky it didnt completly burn the whole place down
Was the shower in use at the time of fire or shortly before to create the heat at the loose connection
So the metering guys came out and didnt even notice/ replace the unofficial TN-S earth strap connection whilst they were there🧐
The DNO would do that, not the supplier/MOP.
I want to say, after seeing two loose-connection consumer unit fires recently... Use RCBOs. Everywhere.
I have encountered multiple installations over here, with bad connections on breakers. They get hot, the conductors are damaged, but the heat on the terminal tends to travel up inside the breaker and the thermal element most often trips before there's a fire.
@Lister Smeg Not specifically by design, and it's not something to always rely on - but yes, only because the heat produced by a loose connection will also heat the internal parts of the breaker, including the thermal trip element, which is exists in an RCBO but not in a plain RCD.
Better not do to much with that shower diet board in case the insurance inspectors have seen it 👍
Must have been loads of flickering lights when that shorted.
Even other houses would have noticed. Same phase houses would have gone dimmer and other phase houses would have gone brighter.
Are you gonna do an update video when it’s finished?
Yes
Romanian looking Noah :))) nice 1 Corey. Greetings from Romania mate.
😁👍