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<p class=MsoNormal>Hey Isaac,</p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I believe that estimating only a 3 percent clipping loss of
harvestable solar power using the M215 with a SW 270 (or any other 270 for that
matter) to be considerably low. Obviously this would depend on installation
location….And for what it’s worth, the ABB 300 actually puts out as much as 330
AC watts. I’ve seen this with my very own eyes with edge-of-cloud conditions
and a SPR 327.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>marco<o:p></o:p></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Marco, here’s a scenario – a bit theoretical, but I’m curious to
get your input since you’ve been active on this topic for a while (I’m assuming
the values below are reasonably accurate – I haven’t looked at the datasheets
for a while):<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='border-collapse:collapse'>
<tr>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
border-left:none;padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>ABB 300’s<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
border-left:none;padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Enphase 215<o:p></o:p></span></p>
</td>
</tr>
<tr>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
border-top:none;padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Max Power<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>300<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>225<o:p></o:p></span></p>
</td>
</tr>
<tr>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
border-top:none;padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Max Current<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>1.25<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>.94<o:p></o:p></span></p>
</td>
</tr>
<tr>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
border-top:none;padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Inverters/Circuit<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>12<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>17<o:p></o:p></span></p>
</td>
</tr>
<tr>
<td width=213 valign=top style='width:159.6pt;border:solid windowtext 1.0pt;
border-top:none;padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>kW/Circuit (based on 270W modules)<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>3.24<o:p></o:p></span></p>
</td>
<td width=213 valign=top style='width:159.6pt;border-top:none;border-left:
none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>4.59<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'>If I have a 100A residential panel with a 100A main, I am
limited to backfeeding a single 20A circuit or doing a supply side
connection. If I got 1500kWh/kW with ABB and 1450 kWh/kW (3% energy loss
due to clipping) with Enphase, would it be worth avoiding the supply side
connection? What if I get 1472 kWh/kW? Where would you draw the
line.<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>
<p class=MsoNormal style='line-height:12.0pt;text-autospace:none'><b><span
style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#5F5F5F'>Isaac
Opalinsky </span></b><span style='font-size:8.0pt;font-family:"Verdana","sans-serif";
color:#5F5F5F'>| Technical Trainer | <b>SunPower Corporation<o:p></o:p></b></span></p>
<p class=MsoNormal style='line-height:12.0pt;text-autospace:none'><span
style='font-size:8.0pt;font-family:"Verdana","sans-serif";color:#5F5F5F'>Desk
443-569-3476 | Cell 443-277-6286<o:p></o:p></span></p>
</div>
<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
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>Marco
Mangelsdorf<br>
<b>Sent:</b> Monday, August 25, 2014 11:11 PM<br>
<b>To:</b> 'RE-wrenches'<br>
<b>Subject:</b> [RE-wrenches] Inverters Maximum Input Ratings<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Look, guys, what’s beyond dispute is that when we size the
solar array higher than the nameplate inverter output, there will be clipping
that takes place….i.e., harvestable solar power that goes nowhere. The
higher that oversize percentage, the more clipping will take place. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>If the design choice, as noted below, is to use a 270-watt
module (from a manufacturer that learned last week that a recall notice was
published by the U.S. Consumer Product Safety Commission <a
href="https://www.cpsc.gov/en/Recalls/2014/SolarWorld-Recalls-Solar-Systems-with-Copper-Grounding-Lugs/">https://www.cpsc.gov/en/Recalls/2014/SolarWorld-Recalls-Solar-Systems-with-Copper-Grounding-Lugs/</a>
), does it make sense to use a micro inverter that has a max output of about
225 watts (M215) or 250 watts (M250) when there are micros (e.g., ABB 300) that
can handle the full output of the 270 which guarantees NO clipping?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>marco<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></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 [<a
href="mailto:re-wrenches-bounces@lists.re-wrenches.org">mailto:re-wrenches-bounces@lists.re-wrenches.org</a>]
<b>On Behalf Of </b>Jerry Shafer<br>
<b>Sent:</b> Monday, August 25, 2014 8:00 PM<br>
<b>To:</b> RE-wrenches<br>
<b>Subject:</b> Re: [RE-wrenches] Inverters Maximum Input Ratings<o:p></o:p></span></p>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p>Why dont you use the m250 anyway as the 250's so far are more reliable then
the 215 have been. A little off topic i know.<o:p></o:p></p>
<div>
<p class=MsoNormal>On Aug 25, 2014 1:41 PM, "Jason Szumlanski" <<a
href="mailto:jason@fafcosolar.com">jason@fafcosolar.com</a>> wrote:<o:p></o:p></p>
<div>
<div>
<p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>I had a
tough customer recently that grilled me on how we can put a 270W solar module
on a 215W inverter. Fortunately, Enphase has a wonderful white paper on the
subject. However, it got me thinking... Enphase has demonstrated that higher
output panels in many climates (hot SW Florida included) can benefit from
modules that far exceed the inverter rating, and even exceed the inverter's
"recommended input" rating. Enphase has shown that 270W+ modules can
show energy harvest on the M215 where it makes sense to "oversize"
the module.<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>I also
received a similar query from a rather uninformed plan reviewer in an area AHJ
along similar lines. Fortunately I was within the "recommended input"
rating on the spec sheet of 270W with a 265W module, but I wonder what would
happen if I had paired the M215 with a 280W module on my plans, which are
becoming readily available now in 60 cell modules with 300W modules on the near
horizon. I'm pretty sure my plan would have been kicked back for exceeding the
manufacturer's recommendation.<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-family:"Verdana","sans-serif"'>My
question, which applies to string inverters and microinverters, is how much is
too much, what would happen if you paired an array that far exceeded the
rating, and how do inverter manufacturers determine the recommended and/or
maximum rating of the connected module or array? Also, why do some
manufacturers have a simple recommendation while others have a
"maximum" rating?<o:p></o:p></span></p>
</div>
<p class=MsoNormal style='margin-bottom:12.0pt'><o:p> </o:p></p>
<div>
<div>
<div style='margin-bottom:6.0pt'>
<p style='margin:0in;margin-bottom:.0001pt'><span style='font-size:10.0pt;
font-family:"Verdana","sans-serif"'>Jason Szumlanski<o:p></o:p></span></p>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Cambria Math","serif"'></span><span
style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Fafco Solar</span><span
style='font-size:10.0pt;font-family:"Cambria Math","serif"'></span><span
style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p></o:p></span></p>
</div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p>
</div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Verdana","sans-serif";
border:solid windowtext 1.0pt;padding:0in'><img border=0 width=1 height=1
id="_x0000_i1025" src="cid:image001.jpg@01CFC12B.2935A610"
alt="Image removed by sender."></span><span style='font-size:10.0pt;font-family:
"Verdana","sans-serif"'><o:p></o:p></span></p>
</div>
</div>
</div>
<p class=MsoNormal style='margin-bottom:12.0pt'><br>
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