Derailed another thread with AFDDs, so I am starting this one. I will simply say that UK RCDs and MCBs provide arc fault protection as is. UL not only knows that, but extensively researched UK power systems in an effort to emulate the very same concept 40 years. One the simply fact (growing concern) that the US National Electrical Code does not prohibit a maximum earth fault loop impedance.
Currently reading:
AFDDs are a massive fraud
Discuss AFDDs are a massive fraud in the UK Electrical Forum area at ElectriciansForums.net
- Reaction score
- 67,273
what about an arc L-L or N-N? e.g. on a fractured cable.
- Reaction score
- 10,616
LOL- asking me for a locationWe can still be friends though
Well you live somewher, presumably?
- Reaction score
- 1,446
Not being that nosey, just getting a feel for the bad habits you may have picked up.
(touch testing for 120V to earth !)
Helps us chose relevant advice.
I have read the thread and it has connotations with other fables I read such as "man did not set foot on the moon"or "the illuminati are hell bent on controlling this planet," (one world government)
Conspiracy theories abound and conspiracy theorists are ever ready to find motive where none may exist
The Iet (bless em) are not anything other than a bunch of sometimes impressionable folk, who happen to have lived their lives(like us) thinking electrons,they are not best placed to accept nonsense too often
They have been and will be susceptible to dodgy influence on occasion but not where technical issues are concerned
The concern in this thread smells like little more than conspiracy theory and big business is on the prowl mentality
Conspiracy theories abound and conspiracy theorists are ever ready to find motive where none may exist
The Iet (bless em) are not anything other than a bunch of sometimes impressionable folk, who happen to have lived their lives(like us) thinking electrons,they are not best placed to accept nonsense too often
They have been and will be susceptible to dodgy influence on occasion but not where technical issues are concerned
The concern in this thread smells like little more than conspiracy theory and big business is on the prowl mentality
Conspiracy theories are just that, theories. People jumping to fantastic conclusions based on incomplete information or bodged journalism.
On the other hand we not only have ample evidence saying so but also science calling AFDDs out as marketing hubris.
Nowhere will you find official documents saying XZY never happened or ABC is just a hologram however here in black and white the creators and researchers of AFCIs freely admit their efforts of trying to mimic European circuit breakers. It can not be any clearer.
Just because a few trolls out in the internet abyss have ruined any view of descent by being vicious unhinged bullies does not make every single person who calls out bad ideas as crazy or a conspiracy theorist.
You do realize that most US electricians hate AFCIs with a passion for all the call backs. Litterally every other day there is a thread on US electrical forums for AFCIs nusinace tripping without cause. The circuit will hold on a GFCI breaker, the romex is meggered, the connections checked and rechecked yet they still trip at random times without reason. Tripping has also been reported for MV faults outside the structure, faults on other circuits and tripping without anything connected the breaker. Even RFI has been known to trip them:
Eaton has since claimed to have resolved the above but nuisance tripping is still going on to this day even with new breakers of all manufacturers.
And by the power of logic if they can trip on LED lighting and functioning appliances who says they can or will trip on supposed dangerous arcing?
- Reaction score
- 4,350
I have not read or looked at what you attached - sorry I am pre-occupied with two projects at the moment.
I have not thought (yet) too much on AFDs and take your point about the UK system with magnetic/thermal mcbs, RCDs and care about wiring and earth fault impedances being successful in some/most situations of detecting parallel arc faults ie between live conductors or between line and earth and neutral and earth. I too am dubious about their efficacy in the UK setting and great potential for nuisance tripping undermining their merit.
I asked earlier 'why now' had AFDs been introduced into our wiring regulations by the IET. I don't know the answer (yet) but assumed it was to deal perhaps with serial arc faults as might be found at loose wiring connections which mcbs and RCDS usually will not detect. But then too there is the great potential for nuisance tripping of AFDs installed to detect serial arc faults as switches are opened and closed. I doubt the current state of AFD technology can distinguish reliably between true serial arc faults of wiring and normal switch operation.
I don't know enough to state a professional opinion on AFDs but do think Cookie is being genuine about how poorly AFDs perform in practice in the USA.
PS: It adds to the interest of a poster if we at least know where they hail from though no need to give one's actual address. Recently, I quite liked to know the EF was helping a chap in Addis Ababa.
I have not thought (yet) too much on AFDs and take your point about the UK system with magnetic/thermal mcbs, RCDs and care about wiring and earth fault impedances being successful in some/most situations of detecting parallel arc faults ie between live conductors or between line and earth and neutral and earth. I too am dubious about their efficacy in the UK setting and great potential for nuisance tripping undermining their merit.
I asked earlier 'why now' had AFDs been introduced into our wiring regulations by the IET. I don't know the answer (yet) but assumed it was to deal perhaps with serial arc faults as might be found at loose wiring connections which mcbs and RCDS usually will not detect. But then too there is the great potential for nuisance tripping of AFDs installed to detect serial arc faults as switches are opened and closed. I doubt the current state of AFD technology can distinguish reliably between true serial arc faults of wiring and normal switch operation.
I don't know enough to state a professional opinion on AFDs but do think Cookie is being genuine about how poorly AFDs perform in practice in the USA.
PS: It adds to the interest of a poster if we at least know where they hail from
though no need to give one's actual address. Recently, I quite liked to know the EF was helping a chap in Addis Ababa.
Last edited:
The plan is to make AFDDs global. The IEC now recommends them thanks to UL being so heavily involved with the IEC and its committees.
I'll find the link, but they also have members from Eaton on those committees. The bias is to obvious.
Truth is they can't. This is the norm in US forums:
Article 700 Emergency power components
Starting with a 700.2 compliant Emergency Power System, also known as Life Safety, with a generator meeting NFPA 110 and an ATS listed under UL1008. Customer wants to add a portable generator docking station with quick-connect plugs (aka CamLok plugs) and a manual transfer switch, also UL1008...
forums.mikeholt.com
But even if they could reliably detect serial arcs (and even glowing connections) mandating them is wrong because code should not dictate technology. Point of use thermal detection can detect serial arcing at fittings and with a much high degree of accuracy in theory. Think Thermarestor as an example. If flex was screened that would detect a series break by tripping the RCD.
The US is rather eye opening, it will tell you everything you need to know.
- Reaction score
- 1,446
Feeling your pain ,
formerly whole houses on dual 30mA RCDs
with similar waking up "in the dark" experiences.
In the name of safety !
- Reaction score
- 1,536
If one world government is a "fable", then why are all these prominent people talking about the creation of a one world government?
Likewise, coincidence theories abound, and coincidence theorists are ever ready to deny motive where motive may have existed.
D
Deleted member 26818
Perhaps I’m cynical?
The 18th edition now has a number of requirements or advisories which appear to have nothing to do with safety, but are more to do with increasing profits for manufacturers.
We can now no longer use anything other than a Type tested DB in domestic installations.
That means we cannot use items of equipment from different manufacturers, even if all of the items of equipment have a greater breaking capacity than the measured PFC.
We now have to follow Manufacturers’ Instructions in respect of DBs.
This means we have to install items of equipment rated at what the manufacturer’s require, rather than rated according to the expected load.
BS7671 now no longer lists RCD sockets or RCD FCUs as being acceptable for additional protection.
This means many installations will require a new DB be installed just to provide RCD protection for an extra socket.
BS7671 now requires circuits supplying luminaires be provided with RCD protection.
So again a new DB when installing an extra light.
We are now advised to install SPDs to prevent damage from lightning strikes.
This is despite the fact that damage to consumer installations from lightning strikes is very rare and occurs much less often than damage caused by loss of supply neutral.
Is it a case of safeguarding the DNOs against compensation claims, rather than protecting customer’s equipment against lightning damage?
As for AFDDs, my understanding, is that they are very unreliable and won’t work with RFCs.
The 18th edition now has a number of requirements or advisories which appear to have nothing to do with safety, but are more to do with increasing profits for manufacturers.
We can now no longer use anything other than a Type tested DB in domestic installations.
That means we cannot use items of equipment from different manufacturers, even if all of the items of equipment have a greater breaking capacity than the measured PFC.
We now have to follow Manufacturers’ Instructions in respect of DBs.
This means we have to install items of equipment rated at what the manufacturer’s require, rather than rated according to the expected load.
BS7671 now no longer lists RCD sockets or RCD FCUs as being acceptable for additional protection.
This means many installations will require a new DB be installed just to provide RCD protection for an extra socket.
BS7671 now requires circuits supplying luminaires be provided with RCD protection.
So again a new DB when installing an extra light.
We are now advised to install SPDs to prevent damage from lightning strikes.
This is despite the fact that damage to consumer installations from lightning strikes is very rare and occurs much less often than damage caused by loss of supply neutral.
Is it a case of safeguarding the DNOs against compensation claims, rather than protecting customer’s equipment against lightning damage?
As for AFDDs, my understanding, is that they are very unreliable and won’t work with RFCs.
It will only get worse unless people put a stop to it. They count on your silence and compliance as consent. US electricians are starting to see the light. Another case in point:
The GFCI requirements are coming from people getting killed on none compliant installations. So how will mandating more GFCIs solve the issue of people refusing to follow the code in the first place? And speaking of that handy work is getting worse because home owners don't understand why an electrician costs 5x as much with call backs vs a handy men that won't cause $500 worth of groceries to go bad when the fridge AFCI trips.
Equipment Grounding question
All, Please see picture attached. Is this the correct size grounding conductor required for equipment grounding? 2 of the power panels have 100A main breaker and the other 2 have 150A main breaker. The transformers are 25KVA. The Fiber panel is a Corning ICH-12P, Nema 3S, I believe. A #4 seems...
forums.mikeholt.com
The GFCI requirements are coming from people getting killed on none compliant installations. So how will mandating more GFCIs solve the issue of people refusing to follow the code in the first place? And speaking of that handy work is getting worse because home owners don't understand why an electrician costs 5x as much with call backs vs a handy men that won't cause $500 worth of groceries to go bad when the fridge AFCI trips.
- Reaction score
- 286
Have a look at the John Ward videos on youtube when he tested one.
Yup, saw them. And a perfect example of why they don't work. Most appliances draw less then 5 amps and most circuits are loaded below that as well. Joule heating can take place under 1 amp. So right here we do not have any fire protection, and above 5 amps its hit or miss... because it may just be an appliance doing its normal thing.
Which brings me to the arc detection logic itself. You need the computing power of at least an Iphone to get reliable discrimination. And even then the AFDD must be programmed to take into account thousands of benign waveforms "learning" what is ok and what isn't. The whole concept even with the right intentions is impractical. Maybe as computing power increases and cost decreases but till then- no.
- Reaction score
- 17,088
If anyone doesn't know what Joule heating is here is a description
joule heating - Bing
Intelligent search from Bing makes it easier to quickly find what you’re looking for and rewards you.
- Reaction score
- 1,446
(That one put me to sleep.)If anyone doesn't know what Joule heating is here is a description
joule heating - Bing
Intelligent search from Bing makes it easier to quickly find what you’re looking for and rewards you.www.bing.com
100% Efficient conversion of electrical energy to heat,
in a region of high relative Resistance ,
I squared R Losses . (or am I wrong)
- Reaction score
- 565
Very interesting thread. And no doubt there are hundreds of firefighters throughout the country breathing a sigh of relief now that they know these things don't work.
They were all thinking they would have to start doing a proper fire investigation instead of the old standby, cause of fire, "electrical".
They were all thinking they would have to start doing a proper fire investigation instead of the old standby, cause of fire, "electrical".
In the US most fires are written off as "electrical". Unless arson is suspected the fire is not thoroughly investigated. And even then its hard to find a cause when all you have is a pile ashes. So fire statsitcs from the states are very skewed.
Interesting fact: fire sprinklers are actually mandated in US homes but its amended out at the local level 99.99% of the time.
- Reaction score
- 565
The Brits have long complained that many Americans don't get irony (for instance, we published a telling story from a British expat last week, and then there was the time the editor of Business Insider UK griped on Twitter about his literal American editors).
Well, there's a reason we don't get irony, and it's not because we're daft.
the British, despite being more low-context than many cultures, are far more high-context than the Americans. Thus they will often say things with implicit meanings that are contrary to their literal meanings — aka irony — that go right over American heads.
www.businessinsider.com
Nothing personal, it's just me. I'm retarded, and am only here for the humour
Well, there's a reason we don't get irony, and it's not because we're daft.
the British, despite being more low-context than many cultures, are far more high-context than the Americans. Thus they will often say things with implicit meanings that are contrary to their literal meanings — aka irony — that go right over American heads.
Here's The Real Reason Americans Don't Get Irony
There's a very good historical reason.
www.businessinsider.com
Nothing personal, it's just me. I'm retarded, and am only here for the humour
- Reaction score
- 67,273
- Reaction score
- 6,974
'Just kidding', tel?you were right the first time.
Reply to AFDDs are a massive fraud in the UK Electrical Forum area at ElectriciansForums.net
Similar Threads
OFFICIAL SPONSORS
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc
YOUR Unread Posts
-
UK Identifying live, neutral and earth in outdoor festoon lighting
- Latest: Richard Cook
-
-
This website was designed, optimised and is hosted by untold.media Operating under the name Untold Media since 2001.