AFDDs & BS7671 Amendment 2 - What you need to know!
The latest version of IET wiring regulations BS7671 Amendment 2 is now a requirement for new UK electrical installations. One of the major changes is the mandatory use of Arc Fault Detection Devices AFDDs in certain types of buildings and applications.
BS7671 AMD2 Effective date 28th September 2022
In partnership with Lewden Palazzoli, we've produced this training module to help update electricians, specifiers and electrical wholesalers.
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Complete the AFDD CPD training module.
👉 hub.efixx.co.uk/lewden-afdd-cpd
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For more FREE Training modules, checkout eFIXX Know How
👉 www.efixx.co.uk/knowhow
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00:00 AFDDs
00:39 Content elements
01:11 Circuit protection
01:50 Overload
02:07 Short circuit
02:35 Old fuses
03:03 Insulation
03:35 RCD
04:07 Arc faults
05:34 Series and parallel arcs
06:11 What is a parallel arc
06:57 Exception to the rule
07:54 Protection for the pugged in load(s)
08:25 AC waveform
08:37 Arc fault waveform
08:53 Inside an AFDD
09:40 Will sparks cause an AFDD to trip
10:44 Overvoltage protection
10:57 Do I still need a type 2 SPD
12:40 Self-test function
13:33 The LED on the AFDD
14:06 What the Regs say about AFDDs
16:00 What does recommend mean
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#BS7671 #electrical #efixx
Complete the AFDD CPD training module. 👉 hub.efixx.co.uk/lewden-afdd-cpd
These training modules are great. Keep them coming 👍🏻
Thankyou for releasing this module, I haven't even watched it all and I going to urgently speaking with my Landlord about upgrading our consumer unit. I could I suppose take your course but I like to avoid anything over 12v. Against that, the course was well written & easy to understand and perhaps I should be remember that just because I will never use it professionally doesn't mean it isn't fascinating!!
I’ve been a spark for 50 years ( now retired ) in all my working life I have seen between 10 /15 spark damaged installations but never a fire …no NEVER a fire .I feel I have missed out so many faults and all the sparks working with me have never mentioned it . So were sparks making the connections to the right torque and now they are not ? Well I’ve never used a torque screwdriver .Maybe the materials used in foregone years were better ?E.L.C.B.s were used when I was an apprentice but now they changed the name to RCD . When I was young the ELCB were voltage or current operated and I really don’t see the difference between RCD and current operated ELCB I think it’s wonderful to put these new devices in homes where no one has any electrical knowledge When the lights go out they won’t be able to use silver paper like they used to so they will wait patiently for Mr Spark to arrive and charge them a fortune .Hope they never break ,the cost of labour and parts will be a little SHOCK in its self .
It's true what you say about issues. Mostly down to cr*p accessories and rushing to get done and onto the next job . Shower pull cords are the most common cause of burnt connections in my experience but don't need an AFDD. Shower pull cords used to have 2 screws per connection, now have one . Cheaply made products cause issues not electricians .
@@dennisphoenix1 you are right about shower pull cords, work of art to get the connections in and in the confines of the back box .
@@raychambers3646 Especially with 10.0 mm.
Seen two burnt out electric shower isolators in my life; one never switched off, the other switched on and off for every shower. The often-operated one fooled the carpenter-owner into changing the electric shower for no good reason...
had to change many shower pull cord switches always the neutral that burnt out, tried using MK 50A switches on a 7Kw shower still had the same problem a year or so later 3 times on one customers ! luckly they moved house , I to was a sparky untill I retired after 50 years all these money making regs changes
AFDD - £155; RCBO - £33. Recommend all you like!
Seem to recall similar arguments when RCD protection became necessary on most circuits. It'll come down. 👍
@@efixx Not with how afdds are currently constructed they won't, having microprocessors in each breaker will never be something that can be made cheap. And RCBOs are actually half the price that jim is saying as well, so the gap is even bigger.
@@AndrewStrydomBRP some early strip downs showed they use stm32 processors, these can be brought on development boards for under £10. At the moment the price probably covers a lot of development and tooling costs.
@@AndrewStrydomBRP simple microprocessors cost just a few pence, these days. You can buy powerful complete boards retail for well under £10.
just don't buy them and the price will come down then. they are in the pockets of iet and we all know it
I see electrolytic capacitors in the breaker. The concern I have is the extremely poor quality of capacitors manufactured in China. Some can fail in two or three years, regardless of load.
Youv'e hit the nail on the head Rob! at the end of the day "You can't polish a turd" we are installing rubbish as EVERYTHING is made in China. It's been a bug-bear of mine for a while now since heads on screws broke off on jobs using a manual screwdriver! this caused more work and gave me less faith in the job I was signing off as good. This country is now built using piles of.....
So stick to well known brands. They have their reputations to protect. They are not going to use cheap fake caps made in China. And when buy the product, check the warranty , and formally record when you purchased the product, take photographs of the receipts, store them securely, and if the product fails and it is still in warranty, then call off against the warranty. And if there is no warranty , keep track of this information anyway because you could make a claim against the retailer for selling products which are not of suitable quality under The Sales of Goods Acts. Products are required to last a reasonable amount of time.
@@deang5622 Nothing to do with fakes. Electrolytic caps age, it's in their nature. Unlike resistors, diodes and transistors that can last indefinitely when treated correctly, the same is not true for those types of caps. Even the (expensive) "long life" types are only rated for 10,000 hours (416 days) at their rated temperature, standard ones at 1,000 to 2,000 hours. And while that can be increased by keeping them cool, even then, their failure rate is only guaranteed to be not worse than 0.5% per 1,000 hours (41 days). Usually, this is no issue, given the typical lifetime of a modern device. Most electronic devices nowadays are used for 5 years or less. But that's not really what people want from a consumer unit. Those should last for decades. My estimate is that AFDDs will have a usable lifetime of about 8 to 10 years before failure rates get high enough that people want them replaced because they don't want their circuits to randomly die. And I expect customers to be quite verbal about expensive stuff in their consumer units dying, that's something they are not used to. Another issue I see is that dead caps could silently disable the arc fault detection circuit by no longer supplying the microchips with power. Those LEDs are nice, but who checks if their breakers are still lit up when they haven't tripped? And who actually expects a consumer to know what a dead LED means?
@@HenryLoenwind I probably know more about caps than you do. They dry out. And drying out doesn't happen over a few years. It takes considerably longer. I used to work for a company that made equipment where the life time of the products were long and the caps were essential to the quality of the output signals produced. We had a cap replacement programme in place for our customers. If caps dried out after a few years we'd all be replacing most of our electronic equipment and that is just not the case, is it? Just apply a bit of logic to it please. I do get irritated when amateurs come along and try to out-do the expert thinking they know more. And your comments out semiconductor devices are incorrect too. And yes, I used to design them . But their failure modes are another story.
@@HenryLoenwind Your post needs a reply that is a little more constructive that the one already provided. Electrolytic caps are rated via 2 values - hours and temperature as you say, but the temp is the key value when it comes to service life. Often the quoted temp is 105C, but what is not made clear is what happens if the operational temp is lower. For many caps the operational life will double for every 10c drop in temp. So a 10,000 hour @ 105C cap will have an estimated life of 20,000 hours @ 95C, 40,000 hours @ 85C, 80,000 hours at 75C and so on. So you need a very poorly installed CU in a very hot location for any good cap to cause a problem.
You stated how AFDD doesn't detect series faults on a ring circuit. However a series fault on a ring circuit would never occur, as the series conductors will always be at the same potential.
Just had a look at the cost from CEF. A 16amp B curve is £155! So an average board will therefore cost around £1500. I think the ‘Shall’ and ‘Recommended’ words might be translated a little differently when the general public realise the costs!😎🍷
Very True
Health and safety has no cost ceiling, Look how many people Died in glenfell started by a fridge fault, AFDD if fitted to the kitchen ring would of prevented this loss of life High rise , HMO, care homes & hospitals this is a no brained addition, £1500 for a DB that should last 25 years that not really a consideration when your the one signing off the work, and would ultimately be held responsible in a court, blaming the untrained customer as not wanting to pay, won’t wash away a manslaughter charge,
I only have 2 socket circuits in my house, my maths might be wrong but that equates to £310, not sure where you're getting £1500 from......unless you're wanting to put AFDD's on every circuit, which isn't the reg so I think the customer can make the decision on how much of their own money they want to spend on their own safety.
@@NicoleBritnell from experience I would fit them to lighting circuits as well as the amount of faults is high and also DIYers fit crap/ badly when it comes to lights
@@oiuslags No it would not. An AFDD does not protect a ring, ( series arc) because there is an alternate route.. Thats why I said earlier, that rings might be brought into question to be replaced by radials. So not only the extra cost, but extra work with radials together with possibly a larger board.
So basically to reduce the reaction that occurred to the public draft document of Amendment 2 to making AFDD's mandatory ("Shall") they used legalese open to misinterpretation instead. As "currently" to detect an arc you need to use an AFDD suggesting that you "Should" install them while having no other alternative available but to fit AFDD's to comply. On a side note several installations that we look after have AFDD's fitted and are having intermittent "Arc Fault" events according to the devices which on subsequent detailed testing and inspection find no cause. The likely cause for some of these may be the occupants appliances and misuse in one instance but all we got as feedback was "The old one didn't do this!!" The manufacturers must be raking it in at £150/device.
Had similar situations of afdd's tripping out. Upon testing all seemed ok. I asked if it was when something in particular was plugged in. 'No I don't think so' came back the answer. Turned out it was a dodgy extension reel used to plug a fan heater in the bedroom that the daughter was using but keeping quiet because the parents moaned at her for using too much leccy.
Legalese? Firstly IET regs are not the law. You should know that by now. Second, there is not uncertainty around the use of language. Shall and should are quite different and are often used in the legal profession and contracts. Perhaps you need to improve your understanding of English. Shall means you must implement it. Should gives you the option of not implementing it, but is preferred. So where there are scenarios described which say "shall", you do not have a choice. You must comply.
As I pointed out in a management meeting some years ago, when someone asked about A new DB and I recommend having all RCBO’s for convince and fitting a more expensive brand, they were not keen to spend the extra money, I pointed out that, your house could if there was a problem burn down while you were out at work, to which people in-the room were moaning about being a bit over the top, so I pointed out “ that their house could also burn down in the middle of the night while your asleep and when you’re putting out the flames on your children’s backs you’re think 3 or 4 hundred quid was a bargain “ The room fell silent and the colour drained from the faces sat around me and the lady from HR sat next to me was nearly sick, at the the potential consequences of a fire at home,
@@deang5622 Not so sure an Insurance inspector would agree after a fire in a new installation of yours-the whole thing needs clarification- the term "recommended" should read MUST!
@@oiuslags Had the same response from an engineer on a big site, telling me he had just saved £80,000 on a switch room. Trouble was the busbars in the isolating switchefuse twisted( fed by 300mm 4 core) and blew out the isolating switch from the panel! Replacement was six weeks and the switch fuse served a huge trading floor! The out come was temp. solid bus bars to breach the gap- I informed him, it could have happen whilst the trading floor was in operation and the £millions liability claim made his £80,000 seem petty.
Lovely easy to understand explanations. However in my 30 years I rarely come across this issue with ring mains, ist usually on shower circuits where the neutral isnt tight enough. But here is no requirement to fit one on shower/cooker circuits!
Don't forget about the appliances connected to the ring final though.... It was one of them that lit the touch paper there...
Yes I'm concerned about the continuously ratchetting up of BS7671. How often do you need an AFDD. Has someone done a cost benefit analysis? In safety the question isn't can it improve safety but is it worthwhile?
What a great video. I am the worst kind of amateur, 30 year old degree in electronics and a 3 day course in 16th edition in 2008. My type thinks they know enough to be competant, but probably make the biggest howling mistakes. This video was great to open my eyes to so much stuff. Beautifully presented, great aids, good pace and explained for our amateur ears to understand. Thank you so much.
Perhaps you could go over the peer reviewed research papers that examine the statistical chances of being killed or injured by an arc fault. Also the subsequent research that actually shows that these devices can and will reduce those chances in real world situations. I assume the recommendations must be based on this data because they would be otherwise largely meaningless. Whilst something may sound like a good idea that does not mean it is actually needed or works in practice.
Great and informative content! I feel always up to date with you guys
Thanks for the clear explanations on this subject.
Thank you for the content. I am not in the UK but it interesting to see what other regions are doing.
Excellent super clear explanation , very impressive way to teach, correct speed, simple graphics, perfect flow. As for the units themselves over complex, expensive and not required in standard 2 storey building. Thanks for the video.
That’s not quite correct - watch 15:37 - 16:50. Also, “a standard two storey building” - is a bit vague - as you could have HMO’s of single / two storeys. If you mean a residential house of two storeys - open to debate as “other properties” mentioned - then it’s “recommended” which becomes you “should” - but you need to do “something” quoting the chap on the video!
The thing that really bugs me about this is it pertains to "AC final circuits supplying socket-outlets with a rated current not exceeding 32 A". IE it doesn't matter if it's a 6 Amp dedicated circuit to one appliance like CCTV or a 16 Amp dedicated to a Microwave, if it's a circuit with sockets on it, it gets an AFDD. What's the one thing we all tend to find arc faults on, Electric Showers. Not included and yet the highest risk and most common. I think it's time to do a Europe and just hard wire everything in and ignore the people writing the regs as they seem to have forgotten what it's like to work out on site on faults and rectification works.
This will promote large rings with some 4mm cable to the 1st socket on each leg of the ring to prevent overheating cable on an unbalanced ring - to save costs. One ring for a whole house, with hard-wired dedicated radials on: Oven, Hob, Immersion.
@@johnburns4017 Which is back to 1960s wiring, and they don't pick up a fault on line-line on rings because it's at the same potential. Basically only protecting against nail-in faults line/neutral or faults with plug in items.
@@effervescence5664 AFDDs highlight an advantage of a ring. If there is an arc, the arc creates a resistance, so the current will, go around the ring from the other direction, reducing any dangerous arcing.
_"AC final circuits supplying_ *_socket-outlets with a rated current not exceeding 32 A"_* So 13A sockets need AFDDs. If you get sockets on a final circuit capable passing over 32A then you are exempt from fitting AFDDs. Are they available in CEF? ;)
Clear and brilliant thank you
Great video with clear and concise explanation, thank you
Perfectly explained!
What a great presentation, it really help to improve my service offer. Warm regards since Querétaro in Mexico
Excellent video very clear - I am an Australian Electrician and like to watch your videos as they are so good -
As always a fantastic presentation. You guys are a great help & your videos really do help. The electrical regs move too quick for me at times.
Move too quick for my wallet.
@@markrainford1219 😂 You’re right there!
I'm not an electrician, but I found this very interesting. Thanks.
Thanks for the informative video - however, the costs for these devices are really very costly and prices need to come down or be offset by significantly lower building insurance premiums.
Well delivered content, thanks 👍
Very interesting video. Thank you for posting it.
Awesome thanks for the info from South Africa
Legend, thanks guys
Microsoft churned out loads of AFDD-equipped power cables for Xboxes years ago, rather than admit that the problem lay within the machine (loose connection on the figure-8 jack due to missing mounting studs). When I tore one down it turned out to be an RCD with the arc fault detection piggybacking onto it. If the AFDD picked up a fault, it introduced an imbalance in the RCD's sense coil to make it trip.
Taking the 18th edition exam on Friday 😃 Been doing a 3 day refresher course since the last regs test I took was when 17th edition was still new
I passed
Congrats!!
Good video eFIXX. Just one criticism, regarding ring finals. It's not that AFDDs won't detect an arc on rings, they will. It's actually that arcs are far less likely to occur on rings. With a single break in the ring, the potential difference between the 2 separated legs would be just a few volts, so no dangerous arcing would occur. Rings are safer than radials in this respect. I still disagree with your interpretation of 'recommend', but we've argued that one before 😉
Yes I totally agree he's got recommend wrong. If he's clarified it with the IET, then they have got it wrong!
@@markrainford1219 I would clarify the meaning of _recommend_ with an Oxford English dictionary.
Yes using the word recommend in a pseudo-mandatory condition would both contravene the normal meaning and the practice of other regulations. If used in this sense its very stupid. Redefining the word in an annex doesn't really help!
Well explained Joe
Wow! very well done!
great content and explanation.. Thanks!
Dual Arc fault and ground fault breakers works wonders, at least here on this side of the pond. They new ones do not nussiance trip as much as they once did.
Very clear explanation.
A fault of negligible impedance? Ohhh, you mean a short circuit 🤣 Everything sounds better in British English!
Thank you for a very interesting and we'll presented video. I am old enough to remember the recommendation in the 1970s to fit a voltage operated protection device (big black things that looked like a switch) and the subsequent issues that occurred as a result. I wonder, how many incidents have occurred over the last five years that AFDDs would have prevented?
Grenfell Tower
That wouldn’t have prevent Grenfil tower the problem was the dryer which caught fire not from the supply feeding it it was an appliance fault this then spread inside the room and to the outer building insulation also my issue is with AFDS there is no way of testing them apart from David saverys home made device. Not convinced by afds on lower loads , seen them in America and I’m not impressed .
Arc faults are fun on three phase gear when you need to run for your life but in domestic properties it is generally less dramatic but big up the IET for this anyway!
Great video as usual, although Lewden are crap. I keep going to boards where the RCD has just stopped working. The test button and RCD test through the Fluke don't work.
Very informative video. Got two questions wrong on what the AFFD lights do in certain faults. I’m sure if I had one to hand it would say what the faults would be mind you 😂
Thinking about addressed sockets and circuit breakers connected a small information screen, we can easly run regarding data over a power lines, forexample socckes 3,4,5 overloaded or rcd stoped because there is is an earth fault on socket 5 , will be big impact especially for restaurants ,hospitals etc
Well presented
not to do with safety anymore, it's what the manufacturer can sell, a licence to print money, just look at the standard of electrical accessories to see how important safety is to the manufacturers
The IET makes its money from the subscriptions of members and the publication and sale of books. It is a registered charity. It is not allowed by law to make profit like a conventional business. The IET does not make money from any suppliers of electrical apparatus. I am sick to death of hearing BS conspiracy theories about the IET that it is introducing regulations so that it can profit from them. *It is not allowed by law to make profit* . That last statement alone should be sufficient to silence you, and silence these mischievous and false assertions others like you make. Either put up the evidence to back up your wild allegations or shut up.
As for accessories. I think you will find there is a whole raft of British Standards the accessories must comply with. Those BS standards exist for safety and to ensure consistency of products made by multiple manufacturers.
I have been in the trade for 45 years and from my own experience I have seen a massive decline in the standard of material supplied, too many manufacturers have sent production to the Far East and the softer materials used for connections now require the use of torque tools. As for the BS standard mentioned in one of the comments, I know what BS used to stand for but these days it stands for something completely different and any experienced Electrician will know what I mean.
Certificate of Europe, CE, is a lot different than BS all geared for the ease of manufacturing cost, as you say anyone that can't see that is in denial, I stand by my previous comment
@@deang5622The 'profit' is a job for life, in swish offices on an excellent salary and a gold plated pension. It's very simple, if there were no new revisions to the 'regs' they would be out of a job. They've had one hundred and forty years and eighteen attempts plus lord knows how many amendments to get it right. You've obviously got a dog in this fight.
remember in 1980's grid fault meant i was called out to work could not keep up with resets till I checked voltage at 260 /265 volt, immediately killed power to factory but dozens of claims for destroyed equipment in houses. This was never made public. Being a small town I tknew through gossip why every fault occured and explaining ,this iis why people got compenation so the 275 volt protection is a bit too highand a bit usless
Great video! A minor niggle: Either the L or N coil in the RCD at 3:39-3:51 should wound in the opposite direction.
Is this only for *new installs* or *new circuits?* Example, a flat on the 7th floor of a 9 floor block has a metal CU with RCBOs on all circuits. Do AFDDs need to be swapped into the socket circuits removing the RCBOs?
Trying to track a Arc fault is going to be fun!
Fantastic video again, considering the fact that AFDD'S have over-voltage protection at 275V, are they a solution to external installations where a PEN Fault would be a problem, like car chargers for example.
This brings to remind of arc - welding.
With all the concern over energy costs, how much does it cost to run each afdd ? The micro controller is going to use some power, and if there are multiple circuits with them on 24/7 is it going to mount up to much? They are already expensive to buy the devices in the first place. I have a feeling that these costs might have the complete opposite effect of intending safety. By way of Joe Schmo from down the pub doing the job for cheap with a screwfix special board rather than legitimate installers doing it as prescribed.
Great video guys. A big help. Can you give an example of “doing something about AFDDS” if they haven’t been fitted where the installations falls out with the 4 key types of premises where they “shall” be fitted?
I wonder about all these add-ons, each of which has a set of contacts that make an arc fault more likely within the device itself (GFI or AFI). Not to mention the expense which is huge. And in North America the ground wire is uninsulated making a parallel arc fault more likely since only one layer of insulation on the hot wire protects against a partial or intermittent short circuit. Band aid solution after band aid solution. I'm starting to think the old 2 wire (no ground) PVC coated wire in my old house (wired approx 1950) is the safer wiring with respect to fire. If there is going to be a ground wire it should be insulated like in much of Europe.
I really feel this regulation should end up being removed just like earthing of metal capping back in the 15th edition. AFDD's are far too expensive and where is the real world science that has driven this through. More pointless amendments causing more trouble than its worth.
What you have to remember is that the Regulations originally were driven by Insurance companies annoyed at having to cover fire cost of poor installations. There might be more to this , than just electrical engineers wanting to change the regs.
The cost should come down over time as demand and supply increases. I think the current "must" requirements and recommendation is a fair balance. I wouldn't like to see it required for all circuits in the near future given the current cost!
Why was the earthing requirement for metal capping removed?
Oh and they don’t work on rings, the circuit that gets the most use in a house 😅
in my experience, the number one cause of wire overheating has been poor connection...either a screw not tightened down, or a bad connector in a junction box
Each AFDD/RCBO cost an average £150 that is a huge extra cost. This will bring into the question the need for ring circuits instead of radials. An AFDD does not detect series arcs on ring mains although it will detect series arcs in appliance cables. So as far as I understand, flammable buildings, ie garden sheds or timber extensions will require full protection of AFDD'S-what does that mean? EVERY circuit has to have a AFDD? We can assume, that all future installations will require some AFDD's, the question is how many and to cover ltg as well? Everything can be considered a fire risk. Will your client be able to claim a reduction in his fire insurance premiums? Its all up in the air. can anyone please clarify?
Could you have a AFDD Main Switch protecting a group of individual circuit breakers? A bit like a Main Switch with a RCD built in?
Possibly but it could lead to issues with unwanted tripping. 🤔
For the test have seen the afdd don't work really well outside of perfect laboratory test, so I don't know what to think about this technology (the arc aren't detected when they should)
Where have you seen them tested please?
Is there a minimum load that the AFDD requires to flow before it will work
Had our consumer board updated recently. Gas fitter fitted new boiler and replaced socket as it was faulty so he could run boiler from it. Unfortunately he failed to connect earth continuity properly and I was electrocuted when touching dishwasher handle (dishwasher fed off same circuit). Trips did’t trip. Still don’t know why nor does electrician who came in to sort it out. The consumer unit uses rcds
What's the additional current consumed by the device! 1watt 24/7 with today's prices will not be cheap
Good vid, BUT does the AFDD circuitry use only passive parts or does it have a micro controller inside with firmware + algorithms to make its fault decisions? Sounds too complex to be just passive. If so, some algorithms are better than others....
You are correct they have a microcontroller / DSP inside to detect specific arc waveforms.
AFDD has already come into its own for me. Just had a job where the customer was concerned about the old wiring and old light fittings. (Fluorescents) Circuit all tested out fine but the AFDD kept disconnecting over a week. Old light fittings changed for new and now no problems.
Great info thanks 🙏
@@efixx all the internals showed signs of thermal degradation but the multifunction tester just saw no problem. Obviously when the fittings had been on long period time something was causing the arc within the gearing. Let alone all the heat degraded wiring within old fluorescents. Also provided good enough evidence that all the lights needed to go.
@@Beariam24 That's why you do periodic test and inspection but nobody wants to pay for that any more, lack of maintenance.
@@leewinters606 100%.
@@Beariam24 just bare in mind when new devices or any other electrical equipment is new on the market you tube channels might be getting a paid promotion the old saying (back handers).shop around and do your research.
I'd like to see one of these passed to bigclive.
He only does £1 LEDs.
Yes that will decide if it's useful or save 1 in 1,000,000,000, 000 000 and if it worth the cost. or a rip off designed by an office guy with spare time
John Ward has done some tests
Who says arc current faults are becoming more common? I find that very unlikely indeed. There is not obvious reason why this should be. Of course, what might be happening is that there's a higher proportion of arc current faults occurring, but that's surely because the other types of faults are becoming less common due to the introduction of MCBs and RCDs (or the combination, in the form of RCBOs). I think with AFDDs we have probably reached the point of strongly diminishing returns. If we want to save lives, far better to upgrade older installations without making the process prohibitively expensive. To my mind, the sweet spot is RCBOs on every individual circuit. Until and unless AFDDs can be reduced in cost to be comparable to RCBOs, that's not worth doing. Frankly, what I am hearing from this is lobbying by the manufacturers of electrical equipment, not independent statistics on how much safer things will be. Artificial tests by Lewden are far from convincing. They have a vested interest in promoting ever more expensive installations.
An Office isnt a Residential Building as defined in the Governments criteria for determining HRRBs as below, which can be viewed on the governments web site. Residential unit "A residential unit is a dwelling or any other unit of living accommodation and is defined in the Act at section 115. Examples of a residential unit are a flat, a studio flat, a home of multiple occupation, shared accommodation within university halls (for example, a bedroom with shared kitchen and bathroom) or a unit within a supported accommodation building. A residential unit can be found within any type of building and could have any tenure. Privately owned, private rented and social rented units are all considered residential units under the higher-risk regime."
So if they protect the flexs that are plugged into a socket on a ring main I assume that they also protect any spurs off a ring main? I'm a homeowner and had them fitted to all my circuits when they replaced my consumer unit. Kinda figured that if they are going to become mandatory it was best to fully upgrade now so I don’t end up having to replace the consumer unit in 5 years time when I want to add something and my consumer unit no longer meets the regulations of the day.
i would like to know how much you paid for that
@@OnlyUseMeEquip £2580 including VAT/ fitting/ testing etc. in 2021 in Bedfordshire (near London). Not cheap I admit but where safety is involved I would rather spend the money to get decent protection. Maybe not your average consumer.
is this another, cant enforce retrspectively kind of thing? but you put a new cct in or you do a new CU. and you need to break the news the customer needs the £150 breaker and not the £15 rcbo...... or can we do the "prayer" detailed in the "gelnwoofit" comment below?
@efixx my question is then, if something has to be done about arc faults on socket-outlets not exceeding 32a and you decide to not choose the afdd costs. Then what alternatives do we have?
People where I live and work can't afford another 600+ pounds on top of the cost of a CU upgrade or a rewire. I wonder who will be making money from these fabulous new must have items.....I know it won't be me
So this £200 part would of prevented genfell , I’m still not sure why these or not being fitted at the front end on the installation not much point in protecting the ring if the main switch is going melt
4:23 Don't you mean 2000? Because at 200, you wouldn't even see it glowing. 6:02 Would the cereal be Weetabix by any chance?
Question: I'm not and electrician but a potential customer who has been considering changing my consumer unit for when I change my kitchen layout, as I need additional circuits and have run out of capacity on my existing unit. When I look on the popular sites like tool station or screwfix, I only see units with MCB & RCBOs. Can't find any unit with AFDDs. Are these the same thing? If not where do you get such devices as the Units being listed are being advertised as being compliant with 'Amendment 2'. Is this a different Amendment 2?
Screwfix have stock of AFDDs. You won’t see them in prebuilt consumer units as AFDDs are only required on socket circuits in certain types of installations such as care homes, student accommodation etc. You can of course go beyond the basic requirements and fit in any installation.
@@efixx Thankyou for the reply. After watching your video I was thinking about attempting to comply with the 'recommended' rules. But seeing that RCBOs with afdd are £150 for a single unit, I think I'll stick with basic RCBOs and buy a new induction HOB instead....
Will the use of a arc welder or mig trip out an arcc? I’m in Australia and was not aware of them. Currently had the house rewired and not mention was made to an arcc. Thanks
AFDDs are to be on final circuits with sockets drawing 32A and below - UK is typically 13A, but higher is permissible in certain situations. An arc welders will have a socket draw over 32A, is not a problem. I would assume an AFDD would detect an arc on an arc welder.
Why no AFDDs on Cooker or Shower circuits - rated at higher than 32A? Surely, these are more susceptible to Arcing and due to the higher currents are more dangerous and in my experience are more than likely the cause of any burning and melting...? Thanks.
Do AFDD's and/or RCBO's have a life span? Ie are they going to fail and need replacing over a period of time?
Does this new reg. apply to new installations or, all current installations as well. It seems that as, with any system that becomes more complex then, MTTF rate is going to increase. The cost and complexity, of such systems, will eventually require higher qualification, than the average electrician.
AFDD mandatory from September 28 for HMO thatched and wooden buildings
Question, If you work on an existing installation (say in a care home) are you expected to install AFDD retrospectively?
Well you would if you were changing the board or adding sockets
Does not with an HMO next inspection in 4 years for me and I will close as it will then
So, when carrying out an EICR on an existing installation of let's say, a high-risk residential building, in the regs it states that AFDD "shall" be used. Would the installation now become unsatisfactory and require remedial works to replace RCBO's/MCB's supplying socket outlets not exceeding 32A with AFDD? This is going to be costly because a lot of installations are using high integrity split load consumer units, there are no AFDD's that can be fitted to those as far as I'm aware.
Although not mentioned in the video I would assume that the fitting of AFDDs is only required on a new installation or an addition to an existing circuit, when carrying out an EICR you could inform the customer about AFDDs but at £150 each plus labour it might be a hard sell but, in any event when carrying out an EICR, if AFDDs are not fitted it is not a retrospective requirement that they must be fitted.
@@andyg1645 Are you sure? You do say _assume._
@@andyg1645 and this is why I'm asking the question, since the requirement of RCD's were written in the same context as what this new regulation states, I would "assume" its to be mandatory on all installations, previous and new... I'm just looking for clarification as I can not seem to find a reputable one from any source without reaching out to IET.
When testing however, how do you detect it? Need an oscilloscope?
You simply spend the day removing everything and finding no visible signs of any arcing before handing the customer a big bill and telling them that it must have been a freak event and to give you a call if it happens again.
*_"Shall"_* is a modal verb used to indicate *future action.* It is most commonly used in sentences with "I" or "we," and is often found in *suggestions,* such as "Shall we go?" "Shall" is also frequently used in promises or *voluntary actions.* There is a difference between _shall_ and _must._
Yes, lawyers will always say to use must as shall is antiquated, but enginers are set in their ways I find.
@@jay-em The wording is such that a 7th floor flat in a block having a new socket circuit does not need to fit an AFDD.
There is, but for BS and ISO, “shall” is used for a requirement (mandatory provision in a standard) and “must” is reserved for external constraints (eg “eggs must be kept warm to hatch”) included for information. Permission (you can, but don’t have to in order to comply with a standard) is always “may”. “Should” is a recommendation; something that is not required for compliance with a standard, but ought usually to be done unless there’s good reason otherwise. If compliance is independently assessed, assessors will usually ask why a “should” provision is not being followed.
@@slrellison It seems they have their own definitions then. But do not tell us what they are. So go by the official dictionary definitions. _[shall] is often found in_ *_suggestions,_* _such as "Shall we go?" "Shall" is also frequently used in promises or_ *_voluntary actions._* Must is well .... _must._ We all know what that means. No ambiguity. Anything else besides _must,_ does not have to be done.
M&Q electrical regulations (actual statute law) always use 'shall', when there is absolutely no excuse in law not to do something.
Residential building over 18 metres high, would that include the entire building like a block of flats? Or would the flats be counted as individual dwellings
Good question. We'll look into it. 👍
@@efixx I would imagine it applies to all floors in an 18m+ building, if there was a fault in a ground floor flat that caused a fire there is a strong likelihood that it would affect the floors above.
When I read the wording of the regulation, I interpreted as applying to the whole building.
Interesting that council flats do not have to comply with regulations mandatory for private landlords
Does the "self test" of the afdd negate the fact these cant be functionally tested like Rcd's and what happens if the afdd pcb goes faulty does it fail open????
Well, I guess it's similar to an MCB, there's no way to functionally test one of those either. I don't know for a fact but I would imagine it fails safe.
does the afdd drive a mechanical or solid state contact to do the switching?
A new very expensive piece of test equipment will no doubt be the next expensive requirement for Electricians to own when the 19th edition comes out.
So would that require affd to be fitted on socket circuits in domestic installation ??
That’s my question also, he talks about the use of the word recommended in the regs but didn’t clarify if this was referring to all domestic ring circuits. If the regs want AFFDs fitted in all domestic properties it will be an uphill battle trying to convince householders that you are not trying to rip them off, especially when they know a guy called Bob in the pub who said he can do the job for a fraction of the quoted price. It was however an otherwise informative video.
@@andyg1645 It's another one of those grey areas. It's recommended rather than optional. As Joe said, if you don't fit them, you need to do SOMETHING which I imagine will be some other form of protection from the same potential danger. AFDD's are the regs PREFERRED option. It's not just ring circuits but all socket circuits. The average domestic property has three socket circuits. Thankfully the regulation doesn't apply to all circuits! I need to replace my parents DB at some point and that has SIX socket circuits! Mike.
AFDD appear to be expensive from some of the comments also RCBO someone said 30 pounds in Aussie they would be $30 sp cheaper here
Greetings and with respect, could you please send me the electrical regulations in PDF format
I am struggling to verify anywhere the definition of “reside” also meaning offices etc i may be completely missing it. This is not meant to challenge what you are informing us of but merely for self clarification. Very informative non the less
That's because you reside in a residence.
@@markrainford1219 i understand this which is why i seek clarity, with reference to the statement at about 1525 on the video where he says ‘residential in this context doesn’t just refer to where people live or sleep, but also includes areas where people may RESIDE during the day for work. So office blocks could be included under these circumstances as well’
Great video but why just sockets?
They are waiting to see how much of a stink this causes, before they roll out 'every circuit' in the nineteenth edition.
Thank you, clear concisely delivered. Grenfell Tower, faulty fridge, Appalling Fire !. Would an AFDD have prevented all those Unnecessary Tragic deaths ?
Depending upon the nature of the electrical fault then yes. We discuss the topic in this video - kzhead.info/sun/obqRcsuke5dsg5s/bejne.html
I suspect that Grenfell Tower had a bad neutral connection somewhere, so that the voltage received in individual flats could deviate considerably from 230v if the loads on each of the three phases supplied to the whole building were not equal. Before the fire the tenants' organisation Grenfell Action Group had been complaining for a couple of years at least about voltage surges that were destroying electrical appliances.
nothing to with that it was the external insulatiion,
@@alanreid3063I thought the Report determined that an electrical appliance caused a fire which then spread to the cladding.
What is the situation with an AFDD when MMA , TIG, or MIG welding at home?
Good question, the answer is I have no idea! I'll make enquiries. 👍
If an AFDD self tests every hour or so. Then why can you not get an AFDD tester?
Why bother with shall or recommendation, just put MUST . Simple . With regards to AFDD'S fault LED indicator it won't show overcurrent or rcd issues for the cause of tripping . Most faults are Rcd tripping . The circuit that the AFDD'S is designed to protect it doesn't work on ( 32A ring mains ) . All this is to protect against poor workmanship as going to metal consumer units has . Poor workmanship is probably the cause of most issues and injury or deaths. You can't stop this with more electronics .
so what am i quoting a customer for a standard 10-13 way consumer unit upgrade with SPD & AFDD?, i currently quote £500 for dual RCD
*Dual RCD is against the regs.* They are clear that a fault on one circuit *must not* affect another circuit. So RCBOs it has to be. I do not know anyone who fits dual RCDs any longer.
This was a really easy, good and understanding video of AFDD`s and really helpful! Another great video from EFIXX. Could you guys please do a video now on SPD`s as after doing the NICEIC webinar last night I was a little confused because they mentioned the possibility of having to install several SPD`s in one installation? I know I`m not the only one to say this. Hot topic at the moment!
I watched that webinar also and what was suggested just sounds insane and unmanageable. Imagine trying to explain and get the go ahead to do that from a customer, let alone execute the installation- to me that would mean fitting an unsightly enclosure at eye level at 10m intervals, fine in a new build or rewire in some respects but on an existing installation how do we know the routes if we didn’t install the cables to know these lengths I’m unsure of also. It just sounds crazy. If this is the case I do not know why they are putting the responsibility of dealing with this on us - bearing in mind we are dealing with the type A situation also, and not onto the manufacturer’s? Why can they not be charged with designing and manufacturing accessories (smokes, heats, c02 etc.) with SPD built in? Surely that is a more sensible idea? The other thing that struck me also was that there has been no mention of this in the limited material on SPD’s that I’ve seen over the past year or so.
Any info on what code no afds on hmo and care homes ect is? - can’t find any info on a exact coding 💁
Mandatory since September 28 for HMO,no insurance cover now unless retrofitted I am advised
Than a AFDD is a better rcbo? 🤔 Or have they be used together? 🤔
Afdd includes an RCBo function
@@efixx thanks
Won't the SPD mask the voltage spikes that the AFDD is looking for?
As far as i can see these are to protect against cheap possibly substandard white goods , any parallel arc will trip a mcb or rcd , they wont detect series arc on a ring final , these are the only circuits we have to install them on.not showers, cookers, immersion heaters or electric heating
A lot of updates to the regs like the use of AFDDs are required to counter the the poor quality materials that we get now and because too many Electricians fail to ensure a good mechanical connection.
Come on. You Can't expect people to honour 60950 ... Thousands of Chinese manufacturers would go bankrupt. All HAIL the MRA !
Question from a non electrical person. Do these AFDD's have to be retrofitted to existing buildings or only new build or rewire or additions to electric circuits.
Only new installations and additions.
My HMO insurance says not covered unless retrofitted with AFDD so will carry the risk until I close the business when next five year test required for a licence
Ok so we don't have to install AFDD's to the average house but "we have to do something"! What other measures are there?
As soon as the IEE can bother to figure that one out it will no doubt be included in the 19th Edition along with some other regs that wouldn’t be required if we actually had good quality materials.
If 'the average' house does not have AFDD for sure insurance companies will not pay out on any electrical cause fires
And if there's a fault the customer will reset it but also no one will still be none the wiser what lead to the arcing in the First place. Its just press reset and carry on
More education for customers required. 👍
@@efixx you can lead a horse to water but you can’t make it drink.