'Proof' that AFCI devices really locate arcs.

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ggunn said:
It's beginning to sound like audiophile gear. :D
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It is only the most discerning of ears that can appreciate the subtle difference between the common cable and the specially-twisted, custom-stranded, over-sized, gold-plated premium cable.

Just ask your buddies the next time they are over watching the game and are yelling at the TV. I'm sure they will agree that the sound is mucho-primo. Perhaps you could pause the game and play a few classical numbers on the stereo to get a solid answer.
 
mbrooke said:
Welcome! :)

The way I see it manufacturers were not even looking to solve a problem, 'AFCI' is simply a price point hatched up by clever marketing. Similar to adding an extra button to a washing machine for a few bucks but raising the cost of the machine by $100 for having an extra feature a lower model does not. Few know that many appliances use the same control board or used the same timers for several different models across a range of prices, all that differs are closing an extra circuit that simply activates another pre-installed program within the chip.


At this point 210.12 needs to be deleted in its entirety.
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It has been of my opinion all along not to be critical of AFCIs as so many have been from the beginning. My position has been to give them some time. The biggest complaint that I found was their added cost and the pain in the butt call backs because of nuisance tripping, some as a result of uncovering a N-G issue because of the GF feature. But there was nothing in regard to them not doing what the manufacturers tauted, that is there mitigation of arcing faults. The manufacturers seems to have addressed the nuisance trippng issue.
My position has always been that the proof is in the pudding, that the insurance industry would recognize and consider them the greatest thing since sliced bread. Over the past 15 years since they were made mandatory it as if they didn't exist at all having no consequence.
That's what my position has always been. I took issue with those who had negative opinions from the the start. But now AFCIs have had enough time to provide examples that the new technology works. To date I can not recall any examples as to detection and preventing fires due to arcing faults. It is time for the AFCI get off of the pot. The NEC should allow thern as an option but not require them.
 
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templdl said:
It has been of my opinion all along not to be critical of AFCIs as so many have been from the beginning. My position has been to give them some time. The biggest complaint that I found was their added cost and the pain in the butt call backs because of nuisance tripping, some as a result of uncovering a N-G issue because of the GF feature. But there was nothing in regard to them not doing what the manufacturers tauted, that is there mitigation of arcing faults. The manufacturers seems to have addressed the nuisance trippng issue.
My position has always been that the proof is in the pudding, that the insurance industry would recognize and consider them the greatest thing since sliced bread. Over the past 15 years since they were made mandatory it as if they didn't exist at all having no consequence.
That's what my position has always been. I took issue with those who had negative opinions from the the start. But now AFCIs have had enough time to provide examples that the new technology works. To date I can not recall any examples as to detection and preventing fires due to arcing faults. It is time for the AFCI get off of the pot. The NEC should allow thern as an option but not require them.
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The N-G issues being uncovered are a good thing being the sign of sloppy work. But the arc logic, forget about it. I think a few extra GFCI breakers and we would have been good.
 
I've studied the UK RCD setups over the past few days and I don't think that kind of system is suitable for North America at all. I simply don't see the need for current differential devices on every single branch circuit in a home. We have a long history of not needing them, so why should that change all of a sudden? Now that being said, I think a 30 mA GFPE breaker (set at the same value as UK RCD's) does have much more value than an AFCI ever will.
 
peter d said:
I've studied the UK RCD setups over the past few days and I don't think that kind of system is suitable for North America at all. I simply don't see the need for current differential devices on every single branch circuit in a home. We have a long history of not needing them, so why should that change all of a sudden? Now that being said, I think a 30 mA GFPE breaker (set at the same value as UK RCD's) does have much more value than an AFCI ever will.
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Why, its cheaper then having a GFCI breaker for each circuit? Just wondering.
 
peter d said:
I've studied the UK RCD setups over the past few days and I don't think that kind of system is suitable for North America at all. I simply don't see the need for current differential devices on every single branch circuit in a home. We have a long history of not needing them, so why should that change all of a sudden? Now that being said, I think a 30 mA GFPE breaker (set at the same value as UK RCD's) does have much more value than an AFCI ever will.
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What is the difference between a RCD and a GFPE?
 
peter d said:
Both are set at 30 milliamps (generally). The main difference is the RCD is purely electro-mechanical, while North American GFPE incorporates electronics. The end result is the same, though.
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Functionally they are the same, but the electromechanical design has the advantage of being surge tolerant. Because electronics are failure prone in that regard new standards require all GFCIs to have a self test feature which again is another excuse to bring up the cost of code mandated installations.

http://www.nema.org/news/Pages/NEMA-and-UL-Announce-Revisions-to-UL-943-GFCI-Standard.aspx

http://www.google.com/url?sa=t&rct=...MdeRSNqCTrBwQ3Z0Q&sig2=jT0HZPkS44TOz0vwC-v4IQ

peter d said:
Because having power cut to a large portion of the house from one fault is unacceptable.
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From a design stand point, not a code stand point. Code should not dictate design, and if you are advocating this I strongly appose it. Only the electrician, builder, engineer or HO should make that call.
 
mbrooke said:
Functionally they are the same, but the electromechanical design has the advantage of being surge tolerant. Because electronics are failure prone in that regard new standards require all GFCIs to have a self test feature which again is another excuse to bring up the cost of code mandated installations.

http://www.nema.org/news/Pages/NEMA-and-UL-Announce-Revisions-to-UL-943-GFCI-Standard.aspx

http://www.google.com/url?sa=t&rct=...MdeRSNqCTrBwQ3Z0Q&sig2=jT0HZPkS44TOz0vwC-v4IQ



From a design stand point, not a code stand point. Code should not dictate design, and if you are advocating this I strongly appose it. Only the electrician, builder, engineer or HO should make that call.
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I'm completely against whole house or partial house RCD protection that is common in the UK, so I'm not sure what you're opposing. :huh:
 
peter d said:
I'm completely against whole house or partial house RCD protection that is common in the UK, so I'm not sure what you're opposing. :huh:
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Against as in code mandating that it cant be done or if manufacturers came out with that option you wouldn't use it?
 
mbrooke said:
Against as in code mandating that it cant be done or if manufacturers came out with that option you wouldn't use it?
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It should not be code mandated. If manufacturers made it available, I would not use it.

That being said, if the powers that be are going to insist that we need additional protection beyond a thermal-magnetic breaker, then I support the use of GFPE on individual branch circuits instead of AFCI's. At least I can see the benefit of GFPE. I would also support manufacturers coming out with a non-electronic GFPE like an RCD in NEMA format.
 
peter d said:
It should not be code mandated. If manufacturers made it available, I would not use it.
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Ahh, ok. Thats how it should be.


That being said, if the powers that be are going to insist that we need additional protection beyond a thermal-magnetic breaker, then I support the use of GFPE on individual branch circuits instead of AFCI's. At least I can see the benefit of GFPE. I would also support manufacturers coming out with a non-electronic GFPE like an RCD in NEMA format.
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I agree, but they should also odder a sub-main approach to contractors looking to save money. Its only fair IMO.
 
mbrooke said:
Ahh, ok. Thats how it should be.





I agree, but they should also odder a sub-main approach to contractors looking to save money. Its only fair IMO.
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Again, a GFPE trip dumping half or all the circuits in a panel is unacceptable in the USA. It might be fine in the UK and elsewhere, but not here.
 
peter d said:
Again, a GFPE trip dumping half or all the circuits in a panel is unacceptable in the USA. It might be fine in the UK and elsewhere, but not here.
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But it should no stop manufacturers from offering that option. They already do with 277/480 volt services of 1000amps and larger.
 
mbrooke said:
But it should no stop manufacturers from offering that option. They already do with 277/480 volt services of 1000amps and larger.
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It's necessary at that voltage level to prevent the switchgear from becoming a pile of molten metal. It's certainly not necessary for 120/240 volt residential services.
 
peter d said:
It's necessary at that voltage level to prevent the switchgear from becoming a pile of molten metal. It's certainly not necessary for 120/240 volt residential services.
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Code doesn't say the GFP MUST protect the switch gear. And ok, lets say it did. Then why isnt selective cordination required? We have all heard of faults on a 20amp lighting home run take out the main.

Here is code blurb btw:




230.95 Ground-Fault Protection of Equipment. Groundfault
protection of equipment shall be provided for solidly
grounded wye electric services of more than 150 volts to
ground but not exceeding 1000 volts phase-to-phase for
each service disconnect rated 1000 amperes or more. The
grounded conductor for the solidly grounded wye system
shall be connected directly to ground through a grounding
electrode system, as specified in 250.50, without inserting
any resistor or impedance device.
The rating of the service disconnect shall be considered
to be the rating of the largest fuse that can be installed or
the highest continuous current trip setting for which the
actual overcurrent device installed in a circuit breaker is
rated or can be adjusted.
Exception: The ground-fault protection provisions of this
section shall not apply to a service disconnect for a continuous
industrial process where a nonorderly shutdown
will introduce additional or increased hazards.
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mbrooke said:
But it should no stop manufacturers from offering that option. They already do with 277/480 volt services of 1000amps and larger.
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:roll:

The manufactures do make GFP for what ever value you want.

But no one wants a GFP main in a house .... No one.
 
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