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--></style></head><body lang="EN-US" link="blue" vlink="purple"><div class="WordSection1"><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Hi Stephen,</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">My most recent experience has been with SMA Tripower and Fronius Symo inverters. Previously, we installed dozens of Power-One (ABB) PVI 10.0 and 12.0 inverters in the < 2015 time period. Although I’ve heard lots of bad stories about those inverters, ours have been quite reliable overall. We had a couple go down that we were replaced under warranty. They were all 208 volt services on those sites for mostly multifamily buildings. </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">We’ve installed the SMA Tripowers in both 1000 VDC and 600 VDC configurations. The 1000 VDC project was hard but I think that’s because it was our first time and we did it right when the inverters were new back in 2013. We have had ongoing problems with one of the 24k units on that site mostly relating to tripping offline due to inductance or arc fault issues. We have replaced the one problem unit and updated firmware several times and now all is well. Other more recently installed sites with the SMA Tripowers worked flawlessly. Tech support with SMA is mostly positive, but sometimes it is hard to get a hold of someone when you need to. </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">We have not commissioned the Fronius Symo sites yet so I can’t comment on how well they work. </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">This is outside of your system target size range, but we recently installed a couple of SolarEdge 14.4 k units. In the 480 volt variant, I think they are available up to 33.3 kW. Anyway, they are amazingly small for their output size and bought us a lot of design flexibility. Only time will tell how reliable the SE inverters and optimizers will be.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">All in all, we always review all options for a given project and start looking at cost compared to design constraints to select the best inverter(s) for the project. I’m hopeful that Fronius’ new line will perform well because their cost and feature set are appealing.</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Cheers,</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">August</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d">Luminalt</span></p><p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1f497d"> </span></p><div style="border:none;border-top:solid #b5c4df 1.0pt;padding:3.0pt 0in 0in 0in"><p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> RE-wrenches [mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>Stephen K<br><b>Sent:</b> Tuesday, August 16, 2016 3:26 PM<br><b>To:</b> <a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a><br><b>Subject:</b> [RE-wrenches] Which commercial string inverters?</span></p></div><p class="MsoNormal"> </p><div><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">Hello RE-Wrenches,</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">I'm a long time recipient of great knowledge, experience and advice from this list, but I've been an infrequent poster.</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">I'm curious about this list's opinion on the current status of the Commercial sized string inverter product options (from ~10kW to 80kW, 600 and 1000VDC flavors). </span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">What are your preferred inverters for ~250kW to ~2MW, US based installations (any mounting type - ground-mount, rooftop, carport etc)? </span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">How would you rank the most well-known brands considering any of the following categories:</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> </span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> a) quality and reliability / uptime</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> b) long-term O&M issues </span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> c) Tech Support and RMA processes</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> d) DAS (or SCADA) factors and challenges</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> e) cost </span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> f) flexibility with design variables</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> g) arc fault issues</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> h) rapid shut down</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> i) firmware/software glitches</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868"> j) other</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">Some brand name suggestions we've become familiar with over the years include - Fronius, SMA, Solectria, Chint, AE, ABB, Kaco, Refusol, Huawei, SunGrow....and more....</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">Thanks for sharing your thoughts everyone,</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> </p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:9.0pt;color:#215868">Stephen Kane</span></b></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:9.0pt;color:#215868">Namaste Solar</span></b></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:9.0pt;color:#215868">Co-Owner | Commercial Service and O&M</span></b></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:9.0pt;color:#215868">NABCEP Certified in Solar PV Installation</span></b></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:9.0pt;color:#215868"><a href="tel:303.447.0300%20x308" target="_blank">303.447.0300 x308</a></span></b></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:9.0pt;color:#215868"><a href="mailto:stephen.kane@namastesolar.com" target="_blank">stephen.kane@namastesolar.com</a></span></b><b><span style="font-size:10.0pt;color:#215868"> </span></b></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">4571 Broadway Street | Boulder, Colorado 80304</span></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:9.0pt;color:#215868">3330 Larimer Street, Suite 1A | Denver, Colorado 80205</span></p></div></div></body></html>