William – Not sure what array size you intend to use, but with the Sunny Boy 3.8-US unit at 208V the max output power is 3.33kW (as current is limited to 16A for breaker sizing at 240V). So 3 of these units gives “balanced” 3 phase 10kW, but at the cost of three inverters.
Two input channels available for each inverter, so you could have an east/west oversized array. Our datasheet specifies the max STC array for the 3.8 is 5396Wp. (Each input cannot be exposed to more than 18A Isc ever, but each channel will draw max 10A in operation.) Each input channel needs 125VDC to start making power, then will work down to 100V (may be lower than CEC efficiency though – I would go for higher voltage fewer strings). And this setup would give the customer three SPS outlets in case of utility outage. Those outlets are 120V each, and cannot be synchronized. Up to 2000W for each, subject to what the array attached to the inverter can produce at any given moment. Best regards – Mike SMA America Michael Mahon Technical Trainer, Solar Academy 6020 West Oaks Boulevard, Suite 300 Rocklin, CA 95765 U.S.A. Mobile: +1 916 918 9412 www.SMA-America.com<http://www.sma-america.com/> Solar Academy: www.SMA-America.com/partners/sma-solar-academy/overview.html<http://www.sma-america.com/partners/sma-solar-academy/overview.html> Full training schedule: https://www.sma-america.com/partners/sma-solar-academy/seminars/trainings/training/list.html [http://sma-planet.sma.de/fileadmin/fm-dam/infos/social_media/facebook.jpg]<http://www.facebook.com/pages/SMA-America/140290312717395> [http://sma-planet.sma.de/fileadmin/fm-dam/infos/social_media/twitter.jpg] <http://twitter.com/SMA_America> [http://sma-planet.sma.de/fileadmin/fm-dam/infos/social_media/wordpress.jpg] <http://www.smainverted.com/> [Linkedin Logo] <http://www.linkedin.com/company/364675> [http://sma-planet.sma.de/fileadmin/fm-dam/infos/social_media/youtube.jpg] <http://www.youtube.com/playlist?list=PL840A5336CAC32332> [SMAAFORUM_ICON] <http://smaadvance.com/signup/> [cid:image008.jpg@01D45E26.3FF7F550] This email and any attachments thereto may contain SMA America, LLC confidential, privileged and private material for the sole use of the intended recipient. Any review, copying, or distribution of this email (or any attachments thereto) by others is strictly prohibited. If you are not the intended recipient, please contact the sender immediately and permanently delete the original and any copies of this email and any attachments thereto. Thank you. From: RE-wrenches <re-wrenches-boun...@lists.re-wrenches.org> On Behalf Of William Miller Sent: Wednesday, January 16, 2019 7:08 PM To: Jerry Shafer <jerrysgarag...@gmail.com>; RE-wrenches <re-wrenches@lists.re-wrenches.org> Subject: Re: [RE-wrenches] Cost of service upgrade vs Solar credits Jerry: Thanks for the reply. If we go three phase I believe we get to pick our voltage. I understand the options are 120/208, 120/240 (open delta) or 277/480. 277/480 won’t work for us because of existing equipment operating at 240 VAC. We have very few 120 loads so a stinger won’t hurt my feelings—I would pick the 120/240. I can do an AB/AC/BC installation with many residential inverters, but at the less than 10K this become problematic: We actually need to split the 10K system size into a 4K and a 6K to offset annual kWh on two meters. By the time you divide these smaller systems into 3 inverters, you don’t have enough panels to meet the MPPT lower threshold. This is where Enphase actually makes some sense. Furthermore, too many string inverters makes the job expensive. It looks like there are real three phase inverter options and I will keep looking. I won’t touch a Fronius. The new equipment may be improved, but I am still burnt by a 500% failure rate of IG inverters and some serious character assassination by Fronius management in dealing with clients. I misquoted the $20K cost to upgrade. This number came from an earlier hypothetical scenario. I need to get real numbers for this project to perform an accurate budget analysis. Thanks for the great input, both online and offline. I feel like we are family. While the complexities of these projects can be a headache, they make the job interesting. William
_______________________________________________ List sponsored by Redwood Alliance 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 List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
