Arc Fault

[don_resqcapt19]

I guess I'm too caught up on my interpretation of the GFI "What goes out must come back" and be equal amounts or I'm going to trip scenario.

which it seems on an Arc Fault Breaker this is not necessarily the case.

This new GE arc fault breaker does not have a ground fault protection circuit so it does not even look at "what goes out must come back".

 

[jap]

Awesome,,,,,,,,,, what goes out can stay out and if something goes wrong with it while its out we'll trip anyway.

 

[al hildenbrand]

This new GE arc fault breaker does not have a ground fault protection circuit so it does not even look at "what goes out must come back".

Exactly!

Jap, that was the real point that I wanted to make before I spiralled off into my rant.

The GE MOD3 seems to be the first of a radically different hardware solution to the grand concept "AFCI".

 

[don_resqcapt19]

...
The GE MOD3 seems to be the first of a radically different hardware solution to the grand concept "AFCI".

However, I think that it loses a lot of functionality without the ground fault detection circuit. I think there are a lot of times that the 30mA GFP will trip long before there is a 5 amp series arc.

 

[al hildenbrand]

However, I think that it loses a lot of functionality without the ground fault detection circuit.

The question that occurs to me is, "Is ground fault detection even a part of the AFCI requirement?"

Have all the 30 - 50 mA ground fault trip levels of other types of AFCIs been part of the early attempts to make what now GE is doing with a signal processor alone? A signal processor that, by itself, actually discriminates between good and bad arcs in the downstream current path? (To me downstream includes the neutral return).

 

[don_resqcapt19]

I don't think that the ground fault is a requirement, but to me it has more functionality than the fancy arc detection circuit. The fancy arc circuit does not even look at anything unless the current exceeds 5 amps. Glowing connections that can produce enough heat to cause a fire can occur at a small fraction that current. With a GFP function and a wiring system with an EGC, there is a good chance that this small current glowing connection will cause a ground fault before it causes a fire.

This is just like it always has been with AFCI..you have to dig very deep to find anything other than hype about how these things work...just look back at the original proposals...they said that the device they had would do what they now say the combination AFCI will do. Those original proposals to require the use of AFCI were made 13 years before the combination type AFCI entered the market.

 

[al hildenbrand]

I could support the incorporation of ground fault detection into the AFCI requirement if tripping was allowed only after the coincident presence of "harmful" arc signatures.

However, the non-discriminating 30 - 50 mA ground fault trip in all present and earlier models (GE MOD 3 excepted) is a blunt safety tool needlessly wasting person hours.

 

[LEO2854]

Two pole AFCI BREAKERS

Two pole AFCI BREAKERS

I could support the incorporation of ground fault detection into the AFCI requirement if tripping was allowed only after the coincident presence of "harmful" arc signatures.

However, the non-discriminating 30 - 50 mA ground fault trip in all present and earlier models (GE MOD 3 excepted) is a blunt safety tool needlessly wasting person hours.

SIEMENS has come with two pole AFCI BREAKERS .
THERE only $80 plus TAX ,I can't wate till they incorp AFCI AND GFCI
I bet they will be $160 a peice
that's going to be a hard sell.
click this link for info.http://www.sea.siemens.com/us/products/residential-electrical/afci/Pages/Siemens_AFCI_Overview.aspx

 

[ELA]

I thought I read someplace, and had believed, that the 30-50ma GF detection inside of an AFCI was to some point a "CYA move" early on.
I examined a QO115CAFCI a couple years back in an attempt to understand enough about the inner workings to be able to discuss their merits and pitfalls with a little deeper level of understanding.

It is much easier to detect a parallel arc since its current level is so high compared to "normal" loads (except inrush, noise etc).
A series arc is harder to discriminate since the current level is well within the "normal" load region.
I think the GF detection may have helped makeup for a lack of a true ability to reliably detect a series arc. Understanding that some manufacturers may be better at it than others.

If I had the spare time I would like to examine the new GE unit without GF detection.
... Never mind, spent way too much time at this last time

 

[al hildenbrand]

If I had the spare time I would like to examine the new GE unit without GF detection.

But you did such good work the last time. . . inquiring minds, etc., eh, nudge, nudge


Seriously, though, I fault the manufacturers for the paucity of tech information about what their various AFCIs actually do. Simply ridiculous.

 

[al hildenbrand]

SIEMENS has come with two pole AFCI BREAKERS .

The feature that the Siemens combination type AFCI have that I find compelling, and handy, is the memory of previous trip and the reporting of it via the two LEDs built into the breaker. I hope this is expanded to a standardized set of error (or activity) codes that are used by all manufacturers.

 

[jap]

Its hard to have the best of both worlds.
Good Arc Fault and or Ground Fault protection without intermitant tripping from a "Non Harmful" arc or ground fault.

Until it can be determined exactly what a "Non Harmful" Fault would be,,,(Which will probably be never).

we'll just keep troubleshooting.

Thanks for everything.

 

[don_resqcapt19]

I could support the incorporation of ground fault detection into the AFCI requirement if tripping was allowed only after the coincident presence of "harmful" arc signatures.

However, the non-discriminating 30 - 50 mA ground fault trip in all present and earlier models (GE MOD 3 excepted) is a blunt safety tool needlessly wasting person hours.

You still lose protection. The AFCIs don't look at low current arc faults that can result in fires. It is my opinion that on a system with an EGC that the GFP circuit will prevent more fires than the arc detection circuit. I also believe that it is "pie in the sky" to think that they will ever be able to make an arc fault detection device that will not false trip from some types of loads that are operating completely with in their normal operating range.

I would support 100% GFCI protection over the currently required AFCI rule.