<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:arial,helvetica,sans-serif;font-size:12pt">Hello wrenches and Marv:<br> How many Enphase inverters do you put on a single parallel string? The Enphase manual allows for up to 15, but I have found that a single string of 15 can have very high voltage rise on the AC wiring. Up to 1.5% loss just on the Enphase cables, and that does not take into account resistance at the plug connectors or any home-run wiring.<br> 15 inverters x 190 watts = 2850 watts<br> 2850 watts / 240 Volts = 11.875 Amps (however at the beginning of the string it is 0 Amps)<br> Average Amps on the Enphase cables is 11.875 / 2 = 5.9375 Amps<br> length of contacts + internal wiring = ~6'<br> Total Enphase cabling length (6' x 15 inverters) =
~90'<br> 5.9375 Amps @ 240 V running 90' on #14 AWG CU = 1.4% loss<br>It is pretty hard to design for 1.5% voltage drop if you have to size for 0% loss on your wiring! I hope Enphase will increase the size of the wire in their cables soon. Have you experienced issues with micro-inverters shutting off due to high AC voltages? <br><div> </div>Nick Soleil<br>Project Manager<br>Advanced Alternative Energy Solutions, LLC<br>PO Box 657<br>Petaluma, CA 94953<br>Cell: 707-321-2937<br>Office: 707-789-9537<br>Fax: 707-769-9037<div><br></div><div style="font-family: arial,helvetica,sans-serif; font-size: 12pt;"><br><div style="font-family: times new roman,new york,times,serif; font-size: 12pt;"><font face="Tahoma" size="2"><hr size="1"><b><span style="font-weight: bold;">From:</span></b> i2p <i2p@aol.com><br><b><span style="font-weight: bold;">To:</span></b> RE-wrenches
<re-wrenches@lists.re-wrenches.org><br><b><span style="font-weight: bold;">Sent:</span></b> Thu, June 10, 2010 4:50:47 PM<br><b><span style="font-weight: bold;">Subject:</span></b> Re: [RE-wrenches] Real world PV production<br></font><br>
<meta http-equiv="x-dns-prefetch-control" content="off"><div><span class="Apple-style-span"><br></span></div><div id="replyPrefaceElement">On Jun 10, 2010, at 7:57:53 AM, "Kelly Keilwitz, Whidbey Sun & Wind" <kelly@whidbeysunwind.com> wrote:</div><br><blockquote style="padding-left: 5px; margin-left: 5px; border-left: 2px solid blue; color: blue;"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; font-size: medium;">PV Watts VASTLY underestimate PV production
in our area.</span></blockquote><div><span class="Apple-style-span">PV Watts underestimates in Central Ca too.<div><span class="Apple-style-span" style=""><br></span></div><div><span class="Apple-style-span" style="">Don</span></div></span></div><div class="aol_ad_footer" id="u9AF4D3CAE2F14AA2984631575C953336"></div><meta http-equiv="x-dns-prefetch-control" content="on"></div></div>
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