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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Im sorry, I meant to write “11 modules per string” below.. <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Been a long day..<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>
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<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"'> Jim MacDonald <br>
<b>Sent:</b> Monday, April 19, 2010 7:41 PM<br>
<b>To:</b> RE-wrenches<br>
<b>Cc:</b> Jason Szrom<br>
<b>Subject:</b> RE: [RE-wrenches] overfeed 7kW gridtie inverter or drop a mod
per string?<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>SB8000US only good for 480 Vac, we’re tying in at 208.<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><s><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>11 strings</span></s><span style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'> </span><span style='font-size:11.0pt;
font-family:"Calibri","sans-serif";color:#1F497D'>[</span><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>11
modules per string</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>] has been calc’d to be OK (<600vdc) for record low -4 fahrenheit
(-20 celsius).<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'>I think the big concern as mentioned is getting the Voc high
early in the AM to wake the inverter up, also maintaining the Vmp later in the
day to keep it running for as long as possible into the late afternoon/
evening.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Will those extra kWh gleaned in the early AM/ late PM over the
course of 365 days be more than the kWh clipped during peak production times
with the 9.075 kWdc?<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>NYC average summer highs between 79 and 84 fahrenheit early
june-late august. Sunlink rack @ 10</span>° <span style='font-size:11.0pt;
font-family:"Calibri","sans-serif";color:#1F497D'>on a silver-painted built-up
roof.<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'>Time-of-use utility $ peak-shaving is not an issue here.<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'>Thank you<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'><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'><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-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>Darryl
Thayer<br>
<b>Sent:</b> Monday, April 19, 2010 5:58 PM<br>
<b>To:</b> RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] overfeed 7kW gridtie inverter or drop a mod
per string?<o:p></o:p></span></p>
</div>
<p class=MsoNormal><o:p> </o:p></p>
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<div>
<p class=MsoNormal>The temperature correction is the concern. I have
heard lots of stories of inverters dieing when it gets to cold. Look in
the code book 690.7 at the temperature correction table. Go to
weather.com and find your record low temperature. Find you Tc factor
and will your senerios work? I have heard from a sunny boy rep that it
is OK to over power by 1.25% <o:p></o:p></p>
</div>
<div>
<p class=MsoNormal>darryl<br>
<br>
--- On <b>Mon, 4/19/10, Dana <i><dana@solarwork.com></i></b> wrote:<o:p></o:p></p>
</div>
<blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0in 0in 0in 4.0pt;
margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'>
<p class=MsoNormal style='margin-bottom:12.0pt'><br>
From: Dana <dana@solarwork.com><br>
Subject: Re: [RE-wrenches] overfeed 7kW gridtie inverter or drop a mod per
string?<br>
To: "'RE-wrenches'" <re-wrenches@lists.re-wrenches.org><br>
Date: Monday, April 19, 2010, 4:31 PM<o:p></o:p></p>
<div id=yiv1929680234>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:14.0pt;font-family:"Arial","sans-serif"'>Many times we switch
to another module manufacturer as one will not fit or another inverter
manufacturer. </span><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:14.0pt;font-family:"Arial","sans-serif"'>PVPowered has a
more relaxed window and we have had fine success with them when SMA does not
fit. </span><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:14.0pt;font-family:"Arial","sans-serif"'>Cold is the
dictator and the 600 VDC threshold.</span><o:p></o:p></p>
</blockquote>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:14.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:14.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>Thanks, Dana Orzel</span><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>Great Solar Works, Inc</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>web - www.solarwork.com</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>E - dana@solarwork.com</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>V - 970.626.5253</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>F - 970.626.4140</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>C - 970.209.4076</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>"We have been slow to give up
on the myth of the Earth's generosity.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>Rather grandly, we have overdrawn
our accounts."</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-family:"Arial","sans-serif"'>Barbara Kingsolver - Water is life.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:14.0pt;font-family:"Arial","sans-serif"'> </span><o:p></o:p></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Arial","sans-serif"'>
re-wrenches-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>Jim
MacDonald<br>
<b>Sent:</b> Monday, April 19, 2010 2:37 PM<br>
<b>To:</b> RE-wrenches@lists.re-wrenches.org<br>
<b>Subject:</b> [RE-wrenches] overfeed 7kW gridtie inverter or drop a mod per
string?</span><o:p></o:p></p>
</div>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>For a straight grid-tie system@ 10 degree tilt, 180
azimuth, zero/little shade, NYC avg 4.29 kWh/m²/day.<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Feed an SMA7000 with (3) strings of 11 Suntech STP275’s
[9.075 kWdc]<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Or<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Do strings of 10, so itd be 8.250 kWdc into the 7 kWac
inverter.<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Strings of 11= 491.7 Voc; 386 Vmp<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Strings of 10= 447 Voc; 351 Vmp <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>The tradeoff would be power clipping at/around noon in the
sunny months in the 9.075 kW scenario;<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Inverter sleeping late every morning and retiring early in
the evenings in the lowered voltage scenario.<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Trying to figure out which would yield more kWh at the end
of the year.<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>Any ideas appreciated,<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'>thanks<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#002060'>Jim MacDonald</span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#002060'>Solar Energy Systems, LLC</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#002060'>Brooklyn, NY 11222</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:#1F497D'><a href="http://www.solaresystems.com/" target="_blank"><span
style='color:blue'>www.solarEsystems.com</span></a></span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'> <o:p></o:p></p>
<p style='margin-left:.5in'><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>No
virus found in this incoming message.<br>
Checked by AVG - www.avg.com<br>
Version: 9.0.801 / Virus Database: 271.1.1/2819 - Release Date: 04/19/10
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