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</o:shapelayout></xml><![endif]--></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'>Hey Gary,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Basically the area of the dropping will lower the current of that module (and the current of that string if this is a string inverter). The amount of current loss will be the % of the dropping area vs the area of the cell it landed on. Voltage won\u2019t be affected by things the scale of a few bird droppings.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If this is a string inverter, theoretically if one module on the string took a hit, then every other module on the string can take a hit too and not really increase the impact, as they are all already current limited by the first module to take a hit. The current of that string will just be the same as the current from the most affected module in the string. So multiple droppings really don\u2019t have a big additive affect.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Assume all birds drop the same size load (you\u2019re not getting seagulls over there so you\u2019re talking starlings, robins, barn swallows, all similar size :) once one module in a string is hit, there will not be any further impact on production until some module in the string gets 2 hits on the <u>same cell on the same module.</u> Cells are just a string mounted in a module frame. So you could have a module with 5 droppings on it if they were all on different cells, and it would do the same as a module with just one dropping, if they were all the same size.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>At some point that above example breaks down, because the bypass diodes will start to kick in if one cell grouping gets hit too hard.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>As for where on the module\u2026.untill you get to the point where bypass diodes are kicking in, I don\u2019t think there is a difference. And at what point would the diodes kick in, you\u2019d need to get an I-V curve tracer out and play around with paintballs or something to help quantify that </span><span style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>J</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That\u2019s the way I understand it at least. I have not gone out with my I-V tracer and dug into this in detail. It\u2019s just based of the core parallel vs series wiring of the typical PV source circuit. I have not seen much impact to date from bird droppings on our Solaredge installs so far (the ones I KNOW where hit by birdie bombers were so close to those that weren\u2019t that I can\u2019t pick them out on the monitoring portal, they just look like typical manufacturing variances [all within the +/- x% power tolerances])<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>With Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Daniel Young, <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>NABCEP Certified PV Installation Professional<sup>TM</sup>: Cert #031508-90<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Lead Systems Designer for:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img width=148 height=90 id="Picture_x0020_11" src="cid:image001.jpg@01D0B802.F739F380" alt="Dovetail 2013 cmyk 300dpi.jpg"><o:p></o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#00B050'><a href="http://www.dovetailsolar.com"><span style='color:#00B050'>www.dovetailsolar.com</span></a><o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Ph: 740-274-0139</span><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#00B050'><o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>We\u2019ve completed nearly 400 renewable energy projects! Check out a few in our photo gallery: </span><b><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="http://www.dovetailsolar.com/Our-Work.aspx?path=commercial+-+solar+electric"><span style='color:#00B050'>http://www.dovetailsolar.com/Our-Work.aspx?path=commercial+-+solar+electric</span></a></span></b><b><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#003399'><o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#92D050'>This email message and attachments are intended only for the addressee. It may contain information which is legally privileged, confidential and exempt from disclosure. If you are not the intended recipient of this message, you may not disclose, print, copy or disseminate this message and/or the information contained in the message. If you have received this message in error, please reply and notify the sender (only) and delete this message along with any attachments. Unauthorized interception of this email is a violation of criminal laws and laws covering electronic communications privacy matters. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></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:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>gary easton<br><b>Sent:</b> Monday, July 06, 2015 3:36 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> [RE-wrenches] Bird droppings<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have a customer with a bit of a bird problem. The array is ground mounted and can be easily cleaned but he is wondering what the impact of for instance droppings on one cell. And how it adds up. Is there a rule of thumb for this? Does it depend where the cell is located in the module?<br><br><br><br>-- <br>Sent from Gmail Mobile<o:p></o:p></p><div class=MsoNormal align=center style='text-align:center'><hr size=1 width="100%" noshade style='color:#A0A0A0' align=center></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>No virus found in this message.<br>Checked by AVG - <a href="http://www.avg.com">www.avg.com</a><br>Version: 2012.0.2250 / Virus Database: 4365/9671 - Release Date: 07/06/15<o:p></o:p></p></div></body></html>