AFCIs That Don't Include GFCI Protection

[Ravenvalor]

Hello,

I read an earlier thread from 2014 on this forum about GE's AFCIs that do not sense for ground faults. Does anyone know of other manufacturers who are now making the same type product? It would be nice to install breakers that do less nuisance tripping.

Thanks,

 

[mbrooke]

If an AFCI is tripping on ground fault that would usually indicate a wiring error which is in violation of the NEC.


From what I have heard Eaton has taken out the GFP on their BR line but not 100% sure.

 

[ActionDave]

GE is the only one I am sure of. I have a foggy thought that Eaton might have dropped in also. The ground fault component detects legitimate faults though, it's the arc sensing that nuisance trips. Usually loads that have electronics freak them out.

I guess my foggy memory isn't so bad.

 

[mbrooke]

GE is the only one I am sure of. I have a foggy thought that Eaton might have dropped in also. The ground fault component detects legitimate faults though, it's the arc sensing that nuisance trips. Usually loads that have electronics freak them out.

I guess my foggy memory isn't so bad.

I agree, the arc detection aspect (wave form analysis) does frequently freak out on electronics like LED lighting and switch mode power supplies. In fact it is often mentioned in research papers that arc detection algorithms fail to discriminate between safe and unsafe arcing:


http://www.mdpi.com/1424-8220/16/4/500/htm

For example, the probability of fire ignition due to arc faults increases from 3.5% for 120 V to 83% for 240 V, and their nominal current levels are both 15 A [49]. Compared to 120 V, the higher voltages from 220 to 240 V are more likely to break down gaps and lead to more arcs [50,51]. Arc currents are usually continuous in higher voltage systems, but they are sometimes intermittent in 120 V systems [49,50]. Thus, higher voltage systems generate larger arc energy and thus provide better conditions for the ignition of electrical fires [50,51].
Furthermore, some commercial AFCIs often fail to trip when necessary or trip when they should not; the accuracy of arc fault detection was only approximately 50% in a previously published research report [39]. Consequently, it remains difficult to accurately detect all arc faults in circuits, and certain detection methods continue to require refinement, especially for 220–240 V operation.

 

[don_resqcapt19]

As far as I know GE and the Eaton CH line are the only ones that have eliminated the ground fault protection from their AFCIs.
It is my opinion that the GFP function does most of the work of the AFCI and is the most important function by far.

The manufactures could not pass all of the required tests for AFCIs when they first came out. All of the original branch circuit/feeder type AFCIs had a GFP function. GFP was never required by the AFCI standard, but it was needed to pass some of the tests. Apparently they have found a way to pass all of the required tests without the GFP function so it is being removed.

 

[mbrooke]

The manufactures could not pass all of the required tests for AFCIs when they first came out. All of the original branch circuit/feeder type AFCIs had a GFP function. GFP was never required by the AFCI standard, but it was needed to pass some of the tests. Apparently they have found a way to pass all of the required tests without the GFP function so it is being removed.

Was this because those tests provided little arcing signature?

 

[al hildenbrand]

As far as I know GE and the Eaton CH line are the only ones that have eliminated the ground fault protection from their AFCIs.

To follow on Ravenvalor's OP question, has any one seen documentation of the Eaton CH AFCI to the effect of Don's report?

 

[ActionDave]

I agree, the arc detection aspect (wave form analysis) does frequently freak out on electronics like LED lighting and switch mode power supplies....

That's been the only problem I've had with them. But when I say only I don't mean to minimize what a nightmare that problem can be to deal with.

 

[mbrooke]

That's been the only problem I've had with them. But when I say only I don't mean to minimize what a nightmare that problem can be to deal with.

And the only none legit reason why they trip. Its unfair that electricians, contractors, customers and appliance manufactures are being used as R&D guinea pigs going on for a period of over 16 years. But that aside one is left with a much greater concern (or more a reasonable question): if AFCI can not tell safe arcing apart from dangerous arcing, what guarantees they can tell dangerous arcing apart from safe arcing? None GFP AFCIs hold that concern entirely. While proper functioning GFP electronics can be guaranteed to trip on a of myriad of dangerous conditions leaking current to ground and also be legitimately tested by shunting 30+ma to the EGC; signature analysis can neither be guaranteed, verified nor tested. Sure there is a test button, but what does that do? Does it simulate (inject) an actual dangerous arc signature into waveform analyzing processor or does it simply verify that the electronics can pull in a trip solenoid?


It is for this reason I believe the OP should not stray away from GFP AFCIs, especially if tripping is coming from the GFP protection itself.

 

[Ravenvalor]

It is for this reason I believe the OP should not stray away from GFP AFCIs, especially if tripping is coming from the GFP protection itself.[/QUOTE]

Great info, thanks for all of the awesome advice to my question. I was hoping to replace a 74 year old breaker panel in a church (or at least put one on the front of it as discussed in this forum in a current thread http://forums.mikeholt.com/showthread.php?t=175975 ). After installing the new panel I was hoping to give the old BX cabling some protection with AFCI multiwire breakers however If I am going to spend a fortune on AFCIs that don't work I might as well sell them regular breakers or leave the entire system in place with the breakers that they are currently using. The customer is getting me the make and catalog number of the breakers and once I get them I will ask Southland Electrical Supply to advise me as to their reliability. I will post the breaker brand and catalog number and what Southland says as soon as I find out.

Here is another great thread where you all discussed AFCIs on MWBCs.

http://forums.mikeholt.com/showthread.php?t=175185&highlight=mwbc

 

[don_resqcapt19]

Was this because those tests provided little arcing signature?

The standard has not changed....they just couldn't find a way to pass of of the required tests without using GFP when they designed the original AFCIs.

 

[al hildenbrand]

As far as I know GE and the Eaton CH line are the only ones that have eliminated the ground fault protection from their AFCIs.

Don, can you point to the documentation on the Eaton CH, please?

 

[mbrooke]

The standard has not changed....they just couldn't find a way to pass of of the required tests without using GFP when they designed the original AFCIs.

I know they have not changed (aside from the series requirement), but my point is those tests themselves, do they produce a poor arc signature? I ask because they involve carbonizing cut insulation rather then an arc in open air across two electrodes.

 

[don_resqcapt19]

Don, can you point to the documentation on the Eaton CH, please?

No paper documentation that I have, but based on information from one of their AFCI design engineers when I talked to him at a trade show.

 

[don_resqcapt19]

I know they have not changed (aside from the series requirement), but my point is those tests themselves, do they produce a poor arc signature? I ask because they involve carbonizing cut insulation rather then an arc in open air across two electrodes.

I have no idea...all I know is that the original AFCIs could not pass the tests that they were required to pass without the GFP function.
He also told me that it is his opinion that the GFP function should be required by the product standard.

 

[al hildenbrand]

No paper documentation that I have, but based on information from one of their AFCI design engineers when I talked to him at a trade show.

Thanks, Don. That makes sense, then.

Eaton web site PDF documents for their single pole combination-type AFCI still instruct avoiding shared neutrals on multiwire circuits and / or avoiding connection of the neutral, on the load side of the breaker, to a secondary conductive path back to the source.

These instructions quack like a duck, that is, they look like there is still a ground fault sensing component still in their combination-type AFCI breakers.

 

[macmikeman]

While we are on this subject, can somebody remind me how much Volkswagen has had to shell out for ''ahem'' fixing the results of tests on vehicle emissions? I am thinking about ditching my orthodontic schtick and becoming a class action circuit breaker attorney.....

 

[mbrooke]

I have no idea...all I know is that the original AFCIs could not pass the tests that they were required to pass without the GFP function.
He also told me that it is his opinion that the GFP function should be required by the product standard.

Who ever he is I agree 100%. GFP offers protection that wave analysis does not.


As for passing that part of the test I will go on a limb here and say it does not produce the same current rich signature as electrode - air - electrode arcing (hint hint ) making detection far more complicated.

 

[don_resqcapt19]

Who ever he is I agree 100%. GFP offers protection that wave analysis does not.


As for passing that part of the test I will go on a limb here and say it does not produce the same current rich signature as electrode - air - electrode arcing (hint hint ) making detection far more complicated.

I did an edit and put the comment in the wrong post.

That was a comment from the Eaton AFCI development engineer that told me the CH AFCI no longer has GFP. He had tried to get it in the AFCI standard without success and I tried to get it as part of the definition of the AFCI in the code, also without success.

 

[kwired]

It is for this reason I believe the OP should not stray away from GFP AFCIs, especially if tripping is coming from the GFP protection itself.

Great info, thanks for all of the awesome advice to my question. I was hoping to replace a 74 year old breaker panel in a church (or at least put one on the front of it as discussed in this forum in a current thread http://forums.mikeholt.com/showthread.php?t=175975 ). After installing the new panel I was hoping to give the old BX cabling some protection with AFCI multiwire breakers however If I am going to spend a fortune on AFCIs that don't work I might as well sell them regular breakers or leave the entire system in place with the breakers that they are currently using. The customer is getting me the make and catalog number of the breakers and once I get them I will ask Southland Electrical Supply to advise me as to their reliability. I will post the breaker brand and catalog number and what Southland says as soon as I find out.

Here is another great thread where you all discussed AFCIs on MWBCs.

http://forums.mikeholt.com/showthread.php?t=175185&highlight=mwbc[/QUOTE]If trying to improve protection of old AC cable without actually replacing it then the GFP component is what you want more then the AFCI component - JMO. If it trips a lot you have real ground fault issues and not GFP protection issues.