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<DIV align=left><FONT color=#000000><FONT size=3 face="Times New Roman">Sounds
like I may be misinterpreting something but I don't think
so...</FONT></FONT></DIV>
<DIV align=left><FONT color=#000000 size=3
face="Times New Roman"></FONT> </DIV>
<DIV align=left><FONT color=#000000><FONT size=3 face="Times New Roman">NFPA 70,
2014 NEC 705.12(D2)(3)(b) states, "</FONT><FONT size=3
face="Times New Roman">The sum of 125% of the inverter(s) output circuit current
and the rating of the </FONT></FONT></FONT></FONT></FONT><FONT size=2
face=Tahoma><FONT size=2 face=Tahoma><FONT size=2 face=Tahoma><FONT size=3
face="Times New Roman">overcurrent device protecting the busbar shall not exceed
120% of the ampacity of the busbar."</FONT></FONT></FONT></FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV align=left><FONT color=#ffffff size=2 face=Tahoma><FONT color=#ffffff
size=2 face=Tahoma><FONT color=#ffffff size=2 face=Tahoma><FONT color=#000000
size=3 face="Times New Roman">Based on this wording, here's an example
of the way I calculate whether or not I'm compliant with the 120%
rule:</FONT></FONT></FONT></FONT></DIV>
<DIV align=left><FONT color=#ffffff size=2 face=Tahoma><FONT color=#ffffff
size=2 face=Tahoma><FONT color=#ffffff size=2 face=Tahoma><FONT color=#000000
size=3 face="Times New Roman">1. Circuit#1 inverter output current rating =
13.5A X 1.25 = 16.88 (OCPD for this circuit = 20A)...(I run 10AWG for these
circuits)</FONT></FONT></FONT></FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman">2. Circuit#2 inverter output
current rating = 9.0A X 1.25 = 11.25 (OCPD for this circuit = 20A)</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman">3. 16.88A + 11.25A =
28.13A</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman">4. 28.13A + 100A (rating of
main OCPD in subpanel) = 128.13A</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman">5. Ampacity of busbar in
125A rated subpanel = 125A</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman">6. 125A X 1.2 =
150A</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman">7. 128.13A < 150A,
therefore, this installation is compliant with 2014 NEC
705.12(D1-D6).</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV align=left><FONT size=3 face="Times New Roman">If I used the 100A rating of
the OCPD instead of the 125A rating of the busbar, I would be limited to
20A of PV instead of 50A.</FONT></DIV>
<DIV align=left><FONT size=3 face="Times New Roman"></FONT> </DIV>
<DIV align=left><FONT size=3 face="Times New Roman">According to the wording in
the NEC I ignore load breakers and only concern myself with OCPD for PV inverter
output circuits and OCPD for the busbar.</FONT></DIV>
<DIV>
<P align=left></FONT><FONT size=2 face=Arial></FONT> </P></DIV>
<DIV>Eric Stikes<BR><!--[if !mso]><![endif]--><!--[if gte mso 9]><xml>
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</o:shapelayout></xml><![endif]-->SunHarvest</DIV></BODY></HTML>