@Cookie
I am somewhat confused here, you seem to be manipulating the debate to suit your position, you on one hand demonstrate how external influences are themselves manipulating regulation and standards by masking results or fudging data to suit their own interests financially and at no point have I disagreed your claims, then on the other hand you use the exact same source of information to confirm your position.... either the UL is reliable or it is not but you cannot use it to make both sides of the argument.
I'm glad you picked up on this and yes it certainly seems that way.
But here is what I'm getting at
1) Because not all of it is lies- its truth with lies mashed together.
2) The UL reports read either way say the IET is wrong to mandate them come time.
Assuming the UL reports are right: RCDs and MCBs detect parallel arcs just as well if note better and all that need to happen is the IET tweaking the loop impedance tables.
Assuming the UL reports are bogus: Insufficient evidence exists that arcing is a problem, is behind fires, or that AFDDs do as claimed. Heavily influenced by external bias from the consumer product safety commission and manufacturers.
I have been in this trade for 30 yrs and I have seen arcing in devices running on 110v and a few amps by design, to say arcing cannot occur at these voltages less than 100amps is a bold sweeping incorrect statement,
Parallel arcing. UL reports say parallel arc are not found below 100amps in the residential setting.
On the other hand, series arcs can be found at any current level- yet in the use AFCIs stop sensing them below 5 amps.
I have seen safety extra low voltages arcing and causing damage to adjacent material especially when the load is inductive by nature and contaminants promote the situation, like I have said before, our standards are aiming at these scenario's and environments, I would question whether UL tested all the possible scenarios which would seem an impossible task given the amount of environmental influences that could promote arcing.
Was it DC? Was it arcing our joule heating?
Remember that joule heating can char anything. Once the heat further loosens the connection some arcing may take place. People often assume when seeing this end stage arcing that the arcing came first and that is what caused the charring.
You also bring up thermarrestors as an alternative solution but fail to recognise the simple issue that an AFDD can monitor a full circuit including load at a small relative cost where as thermarrestors only monitor the location they are applied to a circuit and add additional wiring and installation costs well in excess of the AFDD while giving a fraction of the protection of the circuit. I do recall we had this discussion some 5yrs ago and got a rep on site to present his own pitch which didn't go down too well for him and led him to alter the claims on their website.
Less cost- and less protection.
Joule heating does not produce a waveform, arcing can take place below several amps, and the arc signature might not get caught. AFDDs have serious limitations in being able to discern dangerous series arcing from safe arcing.
Yes every device will need to have thermal monitoring- but I'd rather have something that gets hot spots 100% of the time instead of say 5% of the time.
Now I honestly do not know about cost. I'm guessing it will cost more. And thats a conversation that people in the UK need to have whether or not its worth it.
I will also add thermarrestors cannot be applied to DNO equipment IE the incoming cutout for a few reasons, we cannot connect upstream to cut the power to the cutout nor are we allowed to interfere or adapt their property, here in the UK the cutout in most houses built prior to the 90's is internal connection in the property and that is a substantial section of the UK domestic, commercial and industrial layout, over my time I know several fires caused through cutout loose terminations.
True. But also remember AFDDs will not detect anything on the line side.
So reflecting on my posts and also just to reiterate I am not saying there is no substance to your claims but you have provided evidence from a body to shore up your argument then in other posts discredited them as a valid source due to corrupt influences and agreed with me your youtube link was a mistake, my challenge to present an alternative to AFDD's came back with a solution that totally falls short of the bar, thermarrestors saw the light in approx 2014 in this country as an industry push and never took off, not because of the regulatory restrictions but the fact they simply are not a practical solution and cannot give the same cover as and AFDD...(yes they have their uses but fail to replace the cover of an AFDD) Q' - how does a thermarrestor detect a damage cable that leads to an arc fault, how do you predict where a cable may be damaged for whatever reason be it physical contact, chemical erosion etc etc .. an AFDD does all the above at source and I have already started implemented them in my control panel designs for machinery where we have such problems due to contamination when the machines are not maintained properly.
Point of use thermal dynamics give way better cover then any AFDD ever could and will not fail down the road like electronics when needed most.
A damaged cable is detected by RCDs, MCBs and in the case of flex your fused plugs.
Yes a series break will not get detected in flex, but that can be solved by either screening the cable or setting the bar higher for flex.
I will end that I am not trying to promote or make the claim we should have AFDD's thrust on our regulations but what I am saying is just because you can give examples of corrupt financial influence in the system does not mean their use is not warranted, you haven't given me any real evidence that I cannot find alternative reports that contradict the findings you link to and also what my experience in the industry shows, you keep linking to UL findings which you yourself are attacking as a corrupt organisation. If your concerns are realised then you cannot use their data to prove your position, it is called a circular argument IE akin to using the bible to prove God exists ...
But keep in mind, truth or lies, said corruption says MCBs and RCDs do the same thing in regards to parallel arcing. Then said corruption turns to the IEC/IET and say err no you have dangerous parallel arcing RCDs and MCBs can not detect.
Right here you have the same folks saying two separate things. 180 flip based on the market.
The hubris so blatantly obvious.
Finally here is one of many well established and documented thesis that all come up with similar conclusions all of which contradict some of the claims you make, I therefore put it too you the info you reference is presented out of context, dated, incorrect or simply been misinterpreted, also you fail to address the emerging appliance market that see's HF interference, VFD control which can introduce harmonics into the cables like found in my washing machine and other electrical characteristics like PV that were not relevant only a few decades ago all of which have changed how arc faults behave and effect our installations.
What specifically does the thesis contradict with what I said? Be specific, cite me sentences and figures. I'm not saying you are wrong.
And btw, the VFDs you speak of are making AFDDs way less sensitive because the waveform during normal operation gets mistaken as dangerous arcing.
