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"plug-on neutrals, thus elimination the pig tails"

Damn it!... that was my idea when Arc-faults first came out... i should have done something about it....
 

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Does anybody here know if Chicago enforces arc fault breakers for dwellings?
The make everybody run emt for houses there, so if the breakers are still doing nuisance trips all the time, we could rip apart the "staple driven to hard" malarky from the conversation with some data.
 

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> ....programming that creates a random trip based on the random of the number of times a light switch is turned on or off?

Here is an *early* patent on the AFCI.
http://www.google.com/patents/US4949214



Part 54 is a *counter*. You are correct.

The other diagrams show other, non-counter, ways to discount stray peaks.

While this diagram shows an actual GFI as the switching element, the text discusses other switching types. (I wonder if the *prototype* used a stock GFI because it is easily tripped by an external signal yet fully rated.)

I do *NOT* know if any of the technology shown in this patent is actually used in the AFCIs available today.
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> If you've passed final. Replace the nuisance afci's with normal old breakers.

I have heard an opinion that the NEC is an Installation code and not a Maintenance code.

So having Installed and been Inspected with AFCIs, future maintenance would prefer they be replaced with AFCIs, but the NEC does not enforce that. (Of course the NEC does not enforce anything.)
 

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Modern AFCI

@PRR, note that a modern AFCI uses a small DSP, a microcomputer optimized for processing signals (See http://en.wikipedia.org/wiki/Digital_signal_processing ). These are far more than a simple counter.

But that said, I don't think the world will get a handle on AFCI false tripping until AFCI breakers are eventually connected to the Internet of Things. The existing breakers are open loop: there's no record of how many false trips there are. We all have our stories: mine involve vacuum cleaners and washing machines.

I definitely don't want an AFCI on any sump pump or critical circuit. I'm moderately happy with an AFCI for a safety enhanced Knob & Tube circuit, not because of the wires themselves which are bulletproof, but because of the metal junction boxes.
 
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