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A Troll, may be?????? only asking not accusingYes I do and no I do not. I am disappointed he has not described his background and said where he lives.
Discuss AFDDs are a massive fraud in the UK Electrical Forum area at ElectriciansForums.net
A Troll, may be?????? only asking not accusingYes I do and no I do not. I am disappointed he has not described his background and said where he lives.
TL.DR version. AFDDs are a crap solution to a problem we don't have, use an RFC and forget about them.
In more detail..
From IEC62606-2103
"Residual Current Devices (RCDs) are recognised as efficient to reduce the risk of fire by detection of leakage current and arcing to ground as a consequence of tracking currents within an electrical installation. However, RCDs as fuses or circuit-breakers are not able to reduce the risk of electrical fire due to series or parallel arcing between live conductors.
During a series arc fault, there is no leakage to ground therefore RCDs cannot detect such a fault. Moreover, the impedance of the series arc fault reduces the load current, which will keep the current below the tripping threshold of the circuit-breaker and the fuse. In the case of a parallel arc between phase and neutral conductor, the current is only limited by the impedance of the installation. In the worst cases of sporadic arcs, the conventional circuit breakers were not designed for that purpose."
And the test procedure from IEC62606-2013..
"The insulation across both wires is to be slit 50 mm (or 2 inches) from one end to a depth to expose the conductors without severing any strands.
d) The slit in the insulation is to be wrapped with a double layer of electrical grade black PVC tape and overwrapped with a double layer of fiberglass tape.
e) The conductors are to be stripped at the end farthest from the slit approximately 12 mm (or 0,5 in) for connection to the test circuits. The cable specimen shall be then conditioned to create a carbonized conductive path across insulation between the two cable conductors:
f) The cable specimen is to be connected to a circuit providing 30 mA short circuit current and an open circuit voltage of at least 7 kV. The circuit is to be energized for approximately 10 s or until the smoking stops.
g) The cable specimen is to be connected to a circuit providing 300 mA short circuit at a voltage of at least 2 kV or sufficient to cause the current to flow. The circuit is to be energized for approximately one minute or until the smoking stops."
AFDDs are an attempt to reduce fires in timber buildings using relatively high-current radials, in North America where poor termination and/or breaks in conductors start fires. In the UK RFC's are inherently tolerant of single faults, a feature that makes them incompatible with AFDDs. Given the choice between an RFC and an AFDD it has to be the RFC, it's a cheaper and much more reliable way to reduce the risk of fire from a broken conductor.
Well looking at Cookie's avatar, he is an AMERICAN one of the World's Police Force, the special relationship and all that goes with it,
And I'm assuming he's male. But now we all know, he's just an internet warrior.
A Troll, may be?????? only asking not accusing
I’ve only shared dribs and drabs of mine.I still don't see why you won't share your background. It's the first time I've ever seen this on a forum. You still haven't given a proper reason as far as I can see.
I’ve only shared dribs and drabs of mine.
I still don't see why you won't share your background. It's the first time I've ever seen this on a forum. You still haven't given a proper reason as far as I can see.
Clearly you've never been on a US forum, because AFCI angst literally goes on for 5 dozen pages. Search "Mike Holt AFCIs"
Me too, but it seems a bit deliberate in this case. And when you start making the sort of accusations he is making then it would help. In my opinion anyway.
What type of background would you like me to have? What would have you believe me?
You're just avoiding the issue again.
I never mentioned how long threads go for.
Go and a US forum and you will see plenty of not sharing credentials and people hold AFDD opinions far more extreme then mine.
I give up. I was interested in this thread but its going nowhere for me.
Hi - opinions are like ears, everyone’s got one or two. It’s just human nature to have more respect for statements if there is some background knowledge of the person making them. If you don’t feel you can share, that’s fine .Go and a US forum and you will see plenty of not sharing credentials and people hold AFDD opinions far more extreme then mine.
Hi - opinions are like ears, everyone’s got one or two. It’s just human nature to have more respect for statements if there is some background knowledge of the person making them. If you don’t feel you can share, that’s fine .
I’m a big believer in proper design, installation and testing. I might be wrong, but I think this would remove the need for an AFDD, at least in UK (?).
Hi - yes, I agree, don’t shoot the messenger .But some opinions are based on fact others are based on fiction. I don't understand how my links (openly saying your breakers detect arcing) is not supporting evidence in of itself. I don't care who the messenger is, but rather what is he trying to say and what evidence he has.
Hi - yes, I agree, don’t shoot the messenger .
I am sorry to say that I’ve not looked at your links yet.
GE’s AFCI enables shared neutrals. Ordinarily you would not be able to have just one neutral coming back to the circuit breaker for the AFCI to function properly. GE’s AFCI has the ability to ignore the neutral. You can wire a multi-wire circuit or a shared neutral the same way you would wire a thermal magnetic breaker.
Electricians are above all practical people with a good understanding of theory, certainly in the UK. There has been much theory and academic referencing on AFDDs.
I suggest to Cookie and Sisyphus they now illustrate their criticisms of AFDDs by some examples - case studies - in the domestic, commercial, industrial settings - explaining why they did/did not perform correctly, and what sort of electrical events cause them to trip erroneously? Are there any 'fixes' for when they trip erroneously? How often does nuisance tripping occur? What could be done to improve the detection and threshold rules to reduce nuisance tripping?
What could be done to improve the detection and threshold rules to reduce nuisance tripping?
Having perused this thread, linking out to some of the content to view or read I have found some valid points but also some biased almost on the conspiracy level hype to boot.
The introduction of AFDD's to the UK and the regulations that surround them make there implementation very much different to that of the US, it is very easy to demonstrate that an RCD can stop certain types of arc fault and make it look like a conclusive argument but as other have mentioned this totally ignores parallel and series faults which would not be detected by mcb's and or rcd's.
This alone for me shows an advantage to using AFDD's in certain situations where the environment is such that an arc fault has a heightened risk of causing a fire, in fact the implementation of AFDD's into the BS7671 shows this by specifying these exact situations in the implementation guidelines.
I would argue the point that if this was all just a pointless exercise to make big bucks for certain groups where there were no actually net safety advantage then our regulations would have pushed them onto our market in a very different way.
AFDD's now are very different to those found decades ago, electronic monitoring of arc fault type means a significantly reduced occurrence of nuisance tripping which were the the bane of past generations, remembering here that arcs are naturally part of many electrical household device like vacuum motors so the device needs to distinguish between a natural arc and a fault arc.
I do find the links provided by our American member Cookie are weighted to expose specific and relevant points that support his own beliefs/concerns here but many relevant points that have been raised have not been addressed that counters that view in these links, I also get very skeptical when youtube videos of poorly demonstrated, set-up and measured experiments are part of the defense of position here.
Like I said and has been expressed earlier on, AFDD's cannot be replaced by the use of and RCD and MCB, yes!.. in certain demonstrated scenario's we would expect an rcd to function and negate the need for a AFDD but it is the other types of arc fault that only an AFDD would detect that make them a relevant introduction into the regulations, what should be the argument or discussion here is if the introduction of AFDD's will have an overall positive effect of reducing property damage and subsequently reducing injury and fatality caused by fires derived from an arc fault. Personally I think we already have installation practices and regulations that minimise this in domestic and it is only when we see poor workmanship and/or ignorance to the BS7671 that we have these situations, we already have a legal system that can act on such times, however when we creep into commercial and industrial I do see a genuine benefit in certain scenarios.
It will probably be a decade before we actually know whether they have been effective but I am not convinced on the counter argument and the header of this thread that AFDD's are a massive fraud .. this is a grossly sweeping statement and what I expect of hardcore conspiracy theorists, even making some relevant points and quite good discussion points does not justify the title of this thread, I would also be interested if we can get a response to the very relevant points raised that counter that claim and make AFDD's a viable solution to reduce property fires.
and a limited knowledge of our regulations may be a large part of making such a sweeping bold claim that simply imho has not been shown or demonstrated.
I am not too au fait with how this has all transpired across the pond and on that point I can conclude there is possibly a lot of truth to what you both have said, the point I was trying to make is you seem to be projecting the issues experienced in America onto other very different economical and regulated systems like the UK and thus my comment on the thread title.
I have no doubt at all that big corporates lobby for favourable outcomes that financially benefits themselves and stifles competition and blocks government policy change, that happens everywhere (your own NRA as a classic example).
US regulations and practices for installation protection is very different from ours, AFDD's are been introduced to protect systems of higher risk from such faults where there tends to be a ready source of flammable material near and around electrical equipment i.e. joinery shops, chemical industry etc etc, this hasn't suddenly been thrust on us, it has been implemented after decades of investigations into the most common causes of fire in properties, our system is more transparent than it seems the US is, we can use freedom of information act to get information, studies, polls etc that are used in the lead up to regulatory changes and we do have a period to challenge them, the bodies that implement these changes do give notice years in advance which allows for challenges to be implemented if deemed necessary so I dare say our system is more transparent.
Is the UK system better?.. possible but it is far from perfect, we have our own crosses to bear and our forums are filled with very different repeated content which stems from certain industry bodies pushing regulatory requirements and also the failure to regulate other bodies that has all had an impact on our trade and the regulations that have subsequently been brought in but that's a whole different thread.
What I think this boils down to is your inability to believe that humans make mistakes. That money motivates. That humans lie. That is the limiting factor in all this. Not the counter evidence or their claims.
On balance I do believe that there is credibility in what Cookie is saying. And I respect his right to anonymity. From what he says AFDD is not the l
I don't think that's true. Anyway I haven't time to debate it now, as I'm trying to sell my 6 month old diesel car and the best offer I've had is a fiver.
Now that is a classic! To which I will reply...NO they don't. That is most definitely a false statement. Why do I say that? My experience has showed me again and again having seen the results of arcing on neutrals mostly, that cable and boxes have melted down including MCBs' due to arcing and the MCB just stood and watched. So who will I beleive? You or my lying eyes? As to overcurrent despite all the theory and guff etc. about OCPD and its thermal ability to shut off the supply again not necessarily. On a ring final circuit (32a) someone thought to pop a 10Kw dishwasher. Rather than the MCB operating it preferred to completely melt down without switching off. Bear in mind as to BS7671 when I started out as a trainee it was common to find the neutral fused as well as the line. This was sanctioned by earlier regs. This showed me that they do not know or think about all the things they should! Since then I always have a weather eye as to, does this actually make sense in the real world. Bottom line here, what is the fraud? What is it you actually want help with? Why do you think the AFCI is such a problem with tripping? We here have conjectured that AFDDs' would be tripping out when a fridge compressor switches in or a light switch is switched on it is very much a case of Quod Ed Demonstrandum.UL and Franklin which openly say MCBs prevent arcing.
You haven't read the links. They specifically say MCBs and RCDs mitigate parallel arcing. Specifically. Saying they don't is a giveaway you haven't understood what I have been saying all along.
The above statements are a mystery as to what you are talking about they make no sense and in no way clarify your actual point, which is??????? Forget what bullies have done??? I was nowhere near thinking anything like that I was just trying to get my head around what you are banging on about. You are saying we don't need AFDD, and you and myriad others find them a problem as they keep tripping So? Where is this going? You are saying just use an RCD without any conclusive evidence that it is fine and safe and what will I do in court say you told me so and here are a couple of studies. I need a lot more than that my friend. And believe me if I was convinced of your propositions I would actually take effective action.Forget what bullies have done hiding behind conspiracy theories. I am not one of them.
On the other hand I and countless others in the states know the history and the fall out.
Ultimately you are spot on. The facts, if they are facts, are in no way diminished by method of delivery.Because its not about credentials. Its about the facts I've posted.
" well milud, them went and changed the electrickery din't they, RCDs were perfectly safe in 2017 but 2018's electrickery is different you see so nows we needs they AFDDs so we is all safe from the new electrickery, i thinks".....Where is this going? You are saying just use an RCD without any conclusive evidence that it is fine and safe and what will I do in court.....
I'll double that if of any help?best offer I've had is a fiver
I'll double that if of any help?
Now that is a classic! To which I will reply...NO they don't. That is most definitely a false statement. Why do I say that? My experience has showed me again and again having seen the results of arcing on neutrals mostly, that cable and boxes have melted down including MCBs' due to arcing and the MCB just stood and watched.
So who will I beleive? You or my lying eyes? As to overcurrent despite all the theory and guff etc. about OCPD and its thermal ability to shut off the supply again not necessarily. On a ring final circuit (32a) someone thought to pop a 10Kw dishwasher. Rather than the MCB operating it preferred to completely melt down without switching off. Bear in mind as to BS7671 when I started out as a trainee it was common to find the neutral fused as well as the line. This was sanctioned by earlier regs. This showed me that they do not know or think about all the things they should! Since then I always have a weather eye as to, does this actually make sense in the real world. Bottom line here, what is the fraud? What is it you actually want help with? Why do you think the AFCI is such a problem with tripping? We here have conjectured that AFDDs' would be tripping out when a fridge compressor switches in or a light switch is switched on it is very much a case of Quod Ed Demonstrandum.
But that is exactly what he did say! But look above they do NOT always by any means at all in real life whatever your links say because personally I have witnessed (and I dare say many others on here) MCBs' complete (sometimes) inability to react as theory says they should.
So there you shifted from the statementFailures, joule heating and old designs are not parellel arcing
to "openly prevent parallel arcing" consistency man consistency!UL and Franklin which openly say MCBs prevent arcing.
The above statements are a mystery as to what you are talking about they make no sense and in no way clarify your actual point, which is??????? Forget what bullies have done???
I was nowhere near thinking anything like that I was just trying to get my head around what you are banging on about. You are saying we don't need AFDD, and you and myriad others find them a problem as they keep tripping So? Where is this going? You are saying just use an RCD without any conclusive evidence that it is fine and safe and what will I do in court say you told me so and here are a couple of studies. I need a lot more than that my friend. And believe me if I was convinced of your propositions I would actually take effective action.
So there you shifted from the statement
to "openly prevent parallel arcing" consistency man consistency!
My understanding, is that his test method was not up to par.John Ward tested and wrote off AFDDs in a video on YouTube quite some time ago after testing them.
So there you shifted from the statement
to "openly prevent parallel arcing" consistency man consistency!
BEAMA.So really you think BEAMA is wrong in its contention that they do work and that RCD and MCB are not able to do what an AFDD does
.BEAMA Guide to Arc Fault Detection Devices (AFDDs)
www.beama.org.uk
My understanding, is that his test method was not up to par.
Apparently he should have used a larger load or something.
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