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<DIV><FONT size=2 face=Arial>For claification, the two installs with
which I'm concerned are:</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>1) Grid or 8.5kW Genset ---> Manual transfer
switch ---> FlexPower One w/GVFX3524, FM80, Mate ---> transformer to
240vac ---> Residential Loads. </FONT></DIV>
<DIV><FONT size=2 face=Arial>This set up also has batteries and an
old 600Wstc PV array tied in to the FP1.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>2) Grid or ~10kW Genset determined
by auto transfer switch, all located at utility main
panel/meter located </FONT></DIV>
<DIV><FONT size=2 face=Arial>about 400' from main residence ---> Subpanel and
sub meter at main residence <--- PV-designated subpanel <--- 8.4kW PV
array w/Enphase micros.</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>It's good to hear (thanks Phil) that PV doesn't
auto disconnect when the genny kicks on (didn't think this was the case) but
if the PV does not disconnect don't we end up with PV potentially
backfeeding to the genset?? Isn't this thread discussing how PV backfeeding
to a genny is a dangerous configuration??</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>David, I can't disconnect the GVFX when the grid is
down and the genny on as both grid and genset supply the AC-IN to the inverter
via the manual transfer switch. But your comment begs the question: Why do you
recommend disconnecting the inverter?</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Still trying to connect to an Outback tech (Katee
Wood)...</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV>Eric</DIV>
<DIV><FONT size=2 face=Arial>SunHarvest</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV>----- Original Message ----- </DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px">
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=dkatz@aeesolar.com href="mailto:dkatz@aeesolar.com">David Katz</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=re-wrenches@lists.re-wrenches.org
href="mailto:re-wrenches@lists.re-wrenches.org">RE-wrenches</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, January 16, 2013 8:12
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [RE-wrenches] off grid PV
connected to generator</DIV>
<DIV><BR></DIV>Phil,<BR>If Eric is using the FX ot GTFX in an AC coupled mode,
he would need to disconnect the grid tie inverter when the generator was
running. From the thread, I cannot tell if this is his
situation.<BR>David Katz<BR><BR>Sent from my HTC smartphone on the Now Network
from Sprint!<BR><BR><BR>
<DIV id=htc_header>----- Reply message -----<BR>From: "Phil Undercuffler"
<<A href="mailto:solarphil@gmail.com">solarphil@gmail.com</A>><BR>To:
"RE-wrenches" <re-wrenches@lists.re-wrenches.org><BR>Subject:
[RE-wrenches] off grid PV connected to generator<BR>Date: Tue, Jan 15, 2013
8:07 pm<BR><BR></DIV><BR><BR>
<DIV>
<DIV dir=ltr>
<DIV class=gmail_extra>Eric, </DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>Good questions, and you hit on a number of topics so
let me see if I can address them one at a time, not necessarily in
chronological order. </DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>Yes, the optimal application for the GTFX / GVFX
inverter series is grid tie with battery backup. If you just want backup
to the grid, the traditional FX is a great solution. If you need
extended run-time and want to integrate a generator, then the Radian series is
a better solution because it can not only integrate both grid and generator,
but it can change its operating parameters based on which input it's connected
to. </DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>The SW, XW and Radian inverters are all capable of
operating on-grid (grid-interactive or backup) or off-grid (with or without a
generator). However, none will automatically disconnect the PV when the
genny auto-starts, nor would I suggest that they should. Realistically,
the system should only start the genny when the batteries are near depletion
-- if it's started, the batteries need all the help they can get.
Rather, the generator should only be disconnected (turned off) when the
batteries reach the absorb setpoint. BTW, I can't speak for everyone but
none of those inverters have that functionality, at least not yet.</DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>With 600 Watts of connected PV, I wouldn't worry about
disconnecting the PV. Even with a small battery bank, the sun will set
before that size of array drives the bank anywhere close to an absorb voltage.
Add another zero to the PV size and my answer would be different, of
course.</DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>Also, if you do wind up installing an automatic
transfer switch with a battery-based inverter system, don't allow the ATS to
control the generator starting, even if that flies against every tradition of
the generator sales guy. You don't want the genny running through every
minute of the power outage, you want the system to start the genny only when
the batteries are low.</DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>Good luck with it, and enjoy the sun!</DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra>Phil</DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra><BR></DIV>
<DIV class=gmail_extra><BR>
<DIV class=gmail_quote>On Tue, Jan 15, 2013 at 1:50 PM, SunHarvest <SPAN
dir=ltr><<A href="mailto:eric@harvesthesun.com"
target=_blank>eric@harvesthesun.com</A>></SPAN> wrote:<BR>
<BLOCKQUOTE
style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex"
class=gmail_quote>
<DIV id=:31>Further, I recently installed a GVFX for a customer. I'm hearing
from certain sources that the grid-tied line of inverters from Outback are
not designed to interface with a generator. Really??<BR><BR>I was told by
Outback to install a transfer switch line/supply side of the inverter; that
this was the only way to interface the genny with the inverter; that the AC
Hot In could come from grid or a genset. And indeed, this is the only way I
can figure out how to get the genny to charge the batteries when the grid
goes down. But then again, I don't have the extensive electrical background
that allows me to think outside the box as often as I would like...that's
why I'm posing my query here for the pros. In this Outback install I have to
again advise the homeowner to open the PV breaker to the inverter during
generator operation, right? Even though he has a modest 600W (STC) array and
an 8.5kW Kohler genset. Hardly the opportunity for solar to feed back to the
genny under the most sunny and cool of days. I'm more concerned with the
Enphase install.<BR><BR>The Xantrex SW series inverters are fully capable of
operating on-grid or off-grid with a genset. So do those inverters
automatically disconnect the PV when the genny auto-starts? And with the
Outback, is the Mate supposed to do the same (as long as the genny is
operated by the auto-start and not a transfer
switch)?</DIV></BLOCKQUOTE></DIV><BR><BR></DIV></DIV></DIV>
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