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<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2>Hi Keith,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2>Many of the mainlanders opt for a "supply-side"
interconnection <EM>(tap service conductors between meter and main
breaker).</EM> There are a number of touchy issues with this method if it's in a
single box, and it certainly isn't a "1 size fits all" kinda thing. In case
nobody has said it on the list yet, I'll go ahead with the prediction that we
are likely to see this method become a lot more rare in the future... Unless of
course, your local PV installer has a UL Listed sticker in his back pocket...
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2>In most cases, my preferred option is to install a
main breaker with a lower rating... i.e. Replace the existing 200 Amp breaker
with a 150 Amp breaker. Be sure that the maximum continuous load of the
residence does not exceed 80% of the new main breaker. <EM>(80% x 150A =
120A max continous load)</EM> This example gives you up to 90A of PV Breaker
capacity on a 200A buss.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2>The vast majority of homes with 200A services don't come
anywhere near 120A continous. There are some that do, so make sure you
understand their big electric loads and how they use them. Otherwise, you can
upgrade the service, as you mentioned.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=375342003-10022009><FONT face=Arial
color=#0000ff size=2>Aloha,</FONT></SPAN></DIV>
<DIV align=left><EM><FONT face="Monotype Corsiva" size=4><STRONG>Matt
Lafferty</STRONG></FONT></EM></DIV>
<DIV align=left><FONT face=Arial size=2><A
href="mailto:gilligan06@gmail.com">gilligan06@gmail.com</A></FONT></DIV>
<DIV align=left><FONT face="Stylus BT" size=2><EM></EM></FONT> </DIV>
<DIV> </DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
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<FONT face=Tahoma size=2><B>From:</B> re-wrenches-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] <B>On Behalf Of </B>Keith
Cronin<BR><B>Sent:</B> Monday, February 09, 2009 2:41 PM<BR><B>To:</B>
RE-Wrenches<BR><B>Subject:</B> [RE-wrenches] Point of
connection<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman,new york,times,serif">
<DIV>Hello<BR><BR>With the growth of the solar industry coupled with the
generous incentives now offered on fed part of the equation, we are seeing some
trends here and wondering what the approach has been in other areas. What kind
of feedback are you receiving from the AHJ?<BR><BR>There are some integrators
who now are installing "systems" meaning, multiple small inverters that are
married to smaller arrays as opposed to one large array with one large inverter.
<BR><BR>So, it is quite conceivable to have, for example, 3- 3000 W SMA
inverters on a customers home. So, the point of connection issues arise. When
you look at 690.64B, it speaks to the 120% of the busbar rating.<BR><BR>What are
folks doing in other areas, for this above example to address the
mechanical/electrical challenges associated with this situation, when if you had
1- 200 amp residential service? There is alot of discussion, like installing a
125 amp rated subpanel; interuppting the feeder from the electric service and
installing a 225 amp panel with a higher rated buss (hard to find or custom made
thru Cutler Hammer or others) etc.<BR><BR>We can also see a trend using the
enphase products as well, but not as much pronounced. It could be conceivable
for a client to want to build their system up over a few years and have 15, 175
watt panels on a circuit (2P15 amp) and grow the system up to lets say, 45, 175
watt panels (3-2P15 amp). Same situation, different inverter manufacturer. My
sense is this trend will continue for the forseeable future, and alot of
wrenches will find orphaned systems out there and we should look at ways to
address point of connection issues that are bound to present
themselves.<BR><BR>Thanks<BR><BR>Keith<BR></DIV></DIV><BR></BODY></HTML>