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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'>Just to beat a dead horse and provide additional screen captures, take a look at what is below. “Clipping” is completely the wrong word in this context. It is simply operating at a higher dc voltage on the I-V (not max power). The power quality requirements do not allow systems operating on the utility system to modify their sine wave like many battery-based inverters do under heavy loading conditions. Below are graphs from yesterday’s power output. See how when it hits max power of the inverter, the dc voltage rises. Nice case in point. Also notice that the TL inverter out-produces the non-TL inverter (because of higher efficiency) until max power is reached. At max power, both are the same.<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><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 style='background:white'><tr><td style='padding:0in 0in 0in 11.25pt'><h2 style='line-height:16.5pt'><span style='font-family:"Tahoma","sans-serif";color:black'>3949 Joslin Inverter Comparison<o:p></o:p></span></h2><p class=MsoNormal style='line-height:9.75pt'><span style='font-size:8.5pt;font-family:"Tahoma","sans-serif";color:black'><o:p> </o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=0 style='width:0in;background:white'><tr><td style='padding:0in 0in 0in 0in'><p class=MsoNormal style='line-height:9.75pt'><span style='font-size:8.5pt;font-family:"Tahoma","sans-serif";color:black'><img width=700 height=250 id="UserControlConfigAssistantPlaceHolder_x0024_ctl00_x0024_UserControl0_x0024__diagram" src="cid:image001.png@01CE26DE.50F34B00" alt="cid:6e44facdc93e428095496b438cd56941"></span><span style='font-size:8.5pt;font-family:"Tahoma","sans-serif";color:black'><o:p></o:p></span></p></td></tr><tr><td style='padding:0in 0in 0in 0in'><p class=MsoNormal style='line-height:9.75pt'><span style='font-size:8.5pt;font-family:"Tahoma","sans-serif";color:black'><img width=700 height=250 id="UserControlConfigAssistantPlaceHolder_x0024_ctl00_x0024_UserControl1_x0024__diagram" src="cid:image002.png@01CE26DE.50F34B00" alt="cid:c2f51ce2d7bf493f9c2af46706cf6c66"></span><span style='font-size:8.5pt;font-family:"Tahoma","sans-serif";color:black'><o:p></o:p></span></p></td></tr></table><p class=MsoNormal style='line-height:9.75pt'><span style='font-size:8.5pt;font-family:"Tahoma","sans-serif";color:#F2F7FF'>3/22/2013 10:38:36 AM (UTC) Created by Sunny Portal / SMA Solar Technology AG <o:p></o:p></span></p></td></tr></table><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'>Bill.<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><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>David Brearley<br><b>Sent:</b> Friday, March 22, 2013 8:11 AM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] P1 micro performance<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>The power quality should not be adversely affected. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>While I'm sure different manufacturers may limit power in different ways, in theory all the inverter is doing is moving the array off its MPP. Here's a description from AE:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal><span style='color:#192B7A'>If the power available from the array exceeds the nameplate rating of the inverter, the inverter will limit </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#192B7A'>the power and current coming from the array to the inverter’s maximum nameplate power and </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#192B7A'>current rating. The inverter does this by reducing the DC input current, which causes the DC </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#192B7A'>operating voltage to rise above the maximum power point of the array, thereby ‘clipping’ the </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#192B7A'>array output. This effectively limits the output of the array without stressing the inverter.</span><o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><a href="http://solarenergy.advanced-energy.com/upload/File/Application%20Notes/DCLoadingOfPVPinverters.55-600100-75-A.pdf">http://solarenergy.advanced-energy.com/upload/File/Application%20Notes/DCLoadingOfPVPinverters.55-600100-75-A.pdf</a><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>On Mar 22, 2013, at 9:52 AM, William Dorsett wrote:<o:p></o:p></p></div><div><p class=MsoNormal><br><br><o:p></o:p></p><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>OK, if the upper limit if the curve is “flat topped” do we get increased problems with harmonic noise at the knee as you would in modified “square” wave?</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Bill Dorsett</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Manhattan, KS</span> <o:p></o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>