AFCI Breakers

Status
Not open for further replies.

csoc64

Senior Member
Location
northeast
Does anyone know if any manufacturer has come with AFCI breakers suitable for backfeed? I have been told that Siemens makes them and that they have to be used in a Siemens panel, but I have not been able to locate them.
 

cpinetree

Senior Member
Location
SW Florida
Does anyone know if any manufacturer has come with AFCI breakers suitable for backfeed? I have been told that Siemens makes them and that they have to be used in a Siemens panel, but I have not been able to locate them.

I can't help you, but I am very curious as to your application.
Why do you want or need to back feed an AFCI?
 

SolarPro

Senior Member
Location
Austin, TX
It is highly likely that this requirement goes away during the 2017 revision cycle. (See the shortcircuit's post on p. 2 of the thread jaggedben's post links to.) I happened to talk to a member of CMP 4 earlier this week. There are many proposals for Articles 690 and 705 that are still up for discussion and subject to revision. This is not one of them. I believe the panel voted unanimously to delete the requirement.
 

csoc64

Senior Member
Location
northeast
csoc64
Did you see all the responses the last time you asked about this subject? SolarPro's responses are pretty informative.

If you find any let us know. :D
Thanks for the reminder. Senility is slowly kicking in:blink: I have an AHJ who insists that Siemens makes one, but as I am staring at the spec sheet with a drawing (P/N is Q215AFC), I can clearly see the words "load" and "line" on the drawing. I have a call in to Siemens tech support to specifically ask the question regarding suitability for back-feed.
 

csoc64

Senior Member
Location
northeast
Thanks for the reminder. Senility is slowly kicking in:blink: I have an AHJ who insists that Siemens makes one, but as I am staring at the spec sheet with a drawing (P/N is Q215AFC), I can clearly see the words "load" and "line" on the drawing. I have a call in to Siemens tech support to specifically ask the question regarding suitability for back-feed.
OK, here is what I found. Siemens tech rep advised that "Siemens did not get a UL certification to approve our circuit breakers for reverse feed. However, solar component manufacturer, Enphase, had this testing done and has an appropriate UL certification. I have tried to attach UL letter if anyone is interested. Bottom line, Siemens QAF breakers are UL listed under UL 1741 for use with Enphase Model M250-60-2LL-S22 micro-inverters. View attachment UL Letter for reverse feed 2 pole AFCI from Enphase.pdf
 

shortcircuit2

Senior Member
Location
South of Bawstin
OK, here is what I found. Siemens tech rep advised that "Siemens did not get a UL certification to approve our circuit breakers for reverse feed. However, solar component manufacturer, Enphase, had this testing done and has an appropriate UL certification. I have tried to attach UL letter if anyone is interested. Bottom line, Siemens QAF breakers are UL listed under UL 1741 for use with Enphase Model M250-60-2LL-S22 micro-inverters. View attachment 11981

Enphase circulates this information about AFCI protection all the time...

http://enphase.com/global/files/Enphase_NEC_2014_Compliance.pdf

They never advise using Siemens AFCI with their inverters according to that test.
 

csoc64

Senior Member
Location
northeast
Enphase circulates this information about AFCI protection all the time...

http://enphase.com/global/files/Enphase_NEC_2014_Compliance.pdf

They never advise using Siemens AFCI with their inverters according to that test.
So the technical brief dated January 2015 indicates that "No UL standard for backfeed testing exists for AC AFCI circuit breakers." But the UL letter dated May 21st, 2014 indicates that a standard does exist (UL 1741). I am confused. One supports my case, the other doesn't.
 

shortcircuit2

Senior Member
Location
South of Bawstin
UL 1741 is the standard for inverters.

I all get from the letter you posted is that testing was done and the AFCI breaker worked without problem during those tests. They go on to say it is up to the AHJ on accepting the AFCI if installed. I wouldn't take from that letter that the Siemens AFCI breaker is "listed" for backfeed.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
So the technical brief dated January 2015 indicates that "No UL standard for backfeed testing exists for AC AFCI circuit breakers." But the UL letter dated May 21st, 2014 indicates that a standard does exist (UL 1741). I am confused. One supports my case, the other doesn't.

UL 1741 is the standard for grid-interactive inverters. UL 1699 is the standard for AFCI breakers. With respect to standards, the UL letter is merely stating that Enphase connection via an AFCI breaker did not interfere with the proper operation of the inverters or the AFCI breaker. It's not the same as stating there's a standard specifically for backfeed testing AFCI breakers. The Enphase quote is still true; there is no such standard.

So UL did some testing on one hardware setup, and the hardware passed the test. But installing that hardware still violates the code because the breaker is marked 'line and load' and is not listed to a standard that allows otherwise. I agree that this leaves us in a grey area.
 
Status
Not open for further replies.
Top