I like the idea of some small amount of AC Coupled PV for off-grid systems when there is a known consistent daytime load. Around here the worst case scenario involves afternoon air conditioning in summer, so some WSW-facing AC coupled PV is an efficient way to cover that load and go into darkness with full batteries.
If I understand things correctly, with a Sol-Ark you can simultaneously do AC coupling on the GEN input and DC coupling on the MPPTs and use the GRID input for the generator. Jason On Fri, May 7, 2021, 11:41 AM Dave Tedeyan <d...@sungineersolar.com> wrote: > I would certainly agree with you all that AC coupled for off-grid is not > the best design choice. But just for clarification, this is a grid-tied > system where there is already an Enphase M215 system and a whole house > generator set up. > Cheers, > Dave > > On Fri, May 7, 2021 at 11:10 AM Jerry Shafer <jerrysgarag...@gmail.com> > wrote: > >> I have to agree with Dave on this, complex and off grid generally are not >> good together, l sugest backing up and you might consider a redesign, dump >> enphase, go directly in to the inverter DC side, now a gen set back up will >> work. Your spending more time and effort going in a bad direction. AC >> coupling for resi is not a great solution to start with and Solark even say >> that. KISS is better >> Jerry >> NABCEP PV Inspector >> >> On Thu, May 6, 2021, 7:33 AM Dave Angelini Offgrid Solar < >> offgridso...@sti.net> wrote: >> >>> I would not do any of this for an offgrid client. It is against the rule >>> of less is more. The whole design is flawed in my opinion. >>> >>> >>> >>> *Dave Angelini Offgrid Solar >>> "we go where powerlines don't" >>> http://members.sti.net/offgridsolar/ <http://members.sti.net/offgridsolar/> >>> e-mail offgridso...@sti.net <offgridso...@sti.net> >>> text 209 813 0060* >>> >>> On Tue, 4 May 2021 19:24:13 -0400, Dave Tedeyan <d...@sungineersolar.com> >>> wrote: >>> >>> I suppose the question here is - which is the worse failure mode? >>> A. Solar turning off until an electrician can fix it. >>> OR >>> B. Not knowing the contactor failed until it does not open when the >>> generator turns on and running the risk that the solar backfeeds the >>> generator and breaks it. >>> >>> For off-grid maybe A would be more of a concern. But for grid tied, I >>> would think option B would be worse. >>> >>> Does anyone have a fail safe method of doing this? >>> >>> Cheers, >>> Dave >>> >>> On Tue, May 4, 2021, 4:41 PM Chris Schaefer <ch...@solarandwindfx.com> >>> wrote: >>> >>>> Jason, >>>> >>>> A valid concern which is why I always wire them as powered open so if >>>> there is a failure it would transition closed or not open. >>>> >>>> Christopher >>>> >>>> On Tue, May 4, 2021 at 4:15 PM Jason Szumlanski < >>>> ja...@floridasolardesigngroup.com> wrote: >>>> >>>>> What happens when the contactor fails? I don't trust a NC contactor >>>>> that is supposed to open on 240Vac coil voltage from the generator. It's >>>>> not a failsafe solution. >>>>> >>>>> Jason >>>>> >>>>> >>>>> >>>>> On Tue, May 4, 2021, 3:15 PM Drake < >>>>> drake.chamber...@redwoodalliance.org> wrote: >>>>> >>>>>> P.S. The contactor method is even mentioned somewhere in the Outback >>>>>> literature. I've been using it for years. It is very simple and requires >>>>>> no >>>>>> complex equipment. It will not interfere with rapid shutdown. 40 A, 240 V >>>>>> contactors with 240 V coils are readily available and not terribly >>>>>> expensive. The 240 V output of the generator circuit provides the signal. >>>>>> >>>>>> At 10:02 AM 5/4/2021, you wrote: >>>>>> >>>>>> Get a contactor with a 240 VAC coil. Connect the coil wire wires to >>>>>> the 240 V output circuit of the generator, so when the generator comes >>>>>> on, >>>>>> the contactor opens. Run the current from the AC coupled Enphase >>>>>> inverters >>>>>> through the contacts from common to N/C. >>>>>> >>>>>> --- >>>>>> >>>>>> >>>>>> >>>>>> On 2021-05-03 10:26, Dave Tedeyan wrote: >>>>>> >>>>>> Hi All, >>>>>> >>>>>> I am planning on using a Sol-Ark for the first time for adding >>>>>> battery backup to an existing system. It is Enphase, so clearly it will >>>>>> be >>>>>> AC coupled, and there is a whole house generator. When I talked to >>>>>> Sol-Ark >>>>>> about it, they recommended putting the generator on a time of use >>>>>> schedule >>>>>> to not allow it to come on during the day so that we don't run into the >>>>>> issue of the solar backfeeding the generator. >>>>>> >>>>>> I was wondering though if anyone has just used a contactor to cut out >>>>>> the solar when the generator turns on? Something like Outback's >>>>>> GS-AC-Gen-Kit, although in this case I will need something rated for just >>>>>> over 30A. This seems like a better way to allow the generator to run at >>>>>> any >>>>>> time it is needed, especially if it is a gloomy, snowy, winter day. >>>>>> >>>>>> Cheers, >>>>>> Dave >>>>>> >>>>>> -- >>>>>> >>>>>> *Dave Tedeyan, PE * [image: Sungineer Solar] >>>>>> 1653 Slaterville Road, Ithaca, NY 14850 >>>>>> Cell: 607-288-2898 >>>>>> www.sungineersolar.com >>>>>> >>>>>> _______________________________________________ >>>>>> List sponsored by Redwood Alliance >>>>>> >>>>>> Pay optional member dues here: http://re-wrenches.org >>>>>> >>>>>> List Address: RE-wrenches@lists.re-wrenches.org >>>>>> >>>>>> Change listserver email address & settings: >>>>>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>>>>> >>>>>> There are two list archives for searching. When one doesn't work, try >>>>>> the other: >>>>>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >>>>>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >>>>>> >>>>>> List rules & etiquette: >>>>>> http://www.re-wrenches.org/etiquette.htm >>>>>> >>>>>> Check out or update participant bios: >>>>>> http://www.members.re-wrenches.org >>>>>> >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> List sponsored by Redwood Alliance >>>>>> >>>>>> Pay optional member dues here: http://re-wrenches.org >>>>>> >>>>>> List Address: RE-wrenches@lists.re-wrenches.org >>>>>> >>>>>> Change listserver email address & settings: >>>>>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>>>>> >>>>>> There are two list archives for searching. When one doesn't work, try >>>>>> the other: >>>>>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >>>>>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >>>>>> >>>>>> List rules & etiquette: >>>>>> http://www.re-wrenches.org/etiquette.htm >>>>>> >>>>>> Check out or update participant bios: >>>>>> http://www.members.re-wrenches.org >>>>>> >>>>>> _______________________________________________ >>>>>> List sponsored by Redwood Alliance >>>>>> >>>>>> Pay optional member dues here: http://re-wrenches.org >>>>>> >>>>>> List Address: RE-wrenches@lists.re-wrenches.org >>>>>> >>>>>> Change listserver email address & settings: >>>>>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>>>>> >>>>>> There are two list archives for searching. When one doesn't work, try >>>>>> the other: >>>>>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >>>>>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >>>>>> >>>>>> List rules & etiquette: >>>>>> http://www.re-wrenches.org/etiquette.htm >>>>>> >>>>>> Check out or update participant bios: >>>>>> http://www.members.re-wrenches.org >>>>>> >>>>> _______________________________________________ >>>>> List sponsored by Redwood Alliance >>>>> >>>>> Pay optional member dues here: http://re-wrenches.org >>>>> >>>>> List Address: RE-wrenches@lists.re-wrenches.org >>>>> >>>>> Change listserver email address & settings: >>>>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>>>> >>>>> There are two list archives for searching. When one doesn't work, try >>>>> the other: >>>>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >>>>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >>>>> >>>>> List rules & etiquette: >>>>> http://www.re-wrenches.org/etiquette.htm >>>>> >>>>> Check out or update participant bios: >>>>> http://www.members.re-wrenches.org >>>>> >>>> >>>> >>>> -- >>>> >>>> Chris Schaefer's >>>> <http:www.solarandwindfx.com> >>>> >>>> *Tel/Fax 585-229-2083 or Cell 585-748-1870 * >>>> *5115 South Hill Road ~ Canandaigua New York 14424**www.solarandwindfx.com >>>> <http://www.solarandwindfx.com> ~ E-mail: ch...@solarandwindfx.com >>>> <ch...@solarandwindfx.com>* >>>> >>>> >>>> Thomas Jefferson, the author of our great Constitution, once said, >>>> "democracy" will cease to exist when you take away from those who are >>>> willing to work and give to those who would not." >>>> _______________________________________________ >>>> List sponsored by Redwood Alliance >>>> >>>> Pay optional member dues here: http://re-wrenches.org >>>> >>>> List Address: RE-wrenches@lists.re-wrenches.org >>>> >>>> Change listserver email address & settings: >>>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>>> >>>> There are two list archives for searching. When one doesn't work, try >>>> the other: >>>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >>>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >>>> >>>> List rules & etiquette: >>>> http://www.re-wrenches.org/etiquette.htm >>>> >>>> Check out or update participant bios: >>>> http://www.members.re-wrenches.org >>>> >>> _______________________________________________ >>> List sponsored by Redwood Alliance >>> >>> Pay optional member dues here: http://re-wrenches.org >>> >>> List Address: RE-wrenches@lists.re-wrenches.org >>> >>> Change listserver email address & settings: >>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>> >>> There are two list archives for searching. When one doesn't work, try >>> the other: >>> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >>> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >>> >>> List rules & etiquette: >>> http://www.re-wrenches.org/etiquette.htm >>> >>> Check out or update participant bios: >>> http://www.members.re-wrenches.org >>> >>> _______________________________________________ >> List sponsored by Redwood Alliance >> >> Pay optional member dues here: http://re-wrenches.org >> >> List Address: RE-wrenches@lists.re-wrenches.org >> >> Change listserver email address & settings: >> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >> >> There are two list archives for searching. When one doesn't work, try the >> other: >> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >> >> List rules & etiquette: >> http://www.re-wrenches.org/etiquette.htm >> >> Check out or update participant bios: >> http://www.members.re-wrenches.org >> >> > > -- > *Dave Tedeyan, PE* > [image: Sungineer Solar] > 1653 Slaterville Road, Ithaca, NY 14850 > Cell: 607-288-2898 > www.sungineersolar.com > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > http://www.members.re-wrenches.org > >
_______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://www.members.re-wrenches.org
