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.
-
Please use style selector to select BLUE AND WHITE. If you are not already on it. This notice will go once you're on the correct style.
AFDDs are a massive fraud
Yes, and if twin and earth is damaged a parallel arc is between two points: live to earth or live to neutral. Live to earth is covered with the RCD and breaker coil, live to neutral via the breaker's magnetic trip coil.
So any parallel protection an AFCI offers is redundant at best.
Does anyone in the EF know what the 'tipping point' was to introduce the recent BS7671 requirements for AFDDs? Or did the technology and products become available and were then (necessarily) introduced into the B7671 requirements? Or has the requirement come from a fire brigade investigation and report as did the metal CUs.
Some sensing an Arc before it can produce any sort of heat makes it redundant does it? mind if I ask you a question? firstly you come on the Forum with a legitimate question about possible brown out in a Hospital complex, which turns into a thread comparing US and UK OCPDs RCDS and concluding your argument by saying AFDDs are redundant, Question what is your game?
Well, I don't think you would be to happy if I told you arcing is the end stage of joule heating...
Not so much comparing as showing proof of my claims. Manufacter backed UL and others were literally researching UK/EU power systems with the intent of emulating the system here in the US leading to electronic AFCIs. Now these same manufacturers turn to the IET/IEC claiming they have a new product solving a problem that no technology has ever tackled before.
I derailed in the hospital thread- but since the subject was touched I might as well let knowledge on this hot button issue spill out.
Without going back over the entire thread, What or Who is UL?
USA Underwriters Lab regulatory body
(insurance linked)
Underwriters Laboratories
UL Solutions
UL Solutions is a global independent safety science company with more than a century of expertise innovating safety solutions.
A once none profit that is now a for profit.
Regarding your statement about joules and heating, the AFDD detects an Arc fault before it reverts to combustion, doesn't it?
That what they claim.
Joule heating (aka high resistance connection) are responsible for most electrical fires and in of themselves do not produce arcing. When they do, it is often near the end stage (terminal is already glowing and falling apart), not the start.
That would be when the AFDD trips the circuit Off then before that happens.
Perhaps now, but give it time. They will not only become mandatory, but eventually require self test logic (planed obsolescence) with a slew of devices to also follow. The American NEC is already a product catalog and getting worse each cycle. 2020 is going to be raunchy.
What time is where you are? Sun's over the yardarm here, I'd recommend a stiff drink, or whatever trips your device.
Hi everyone,
If...
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
