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<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>(This has already been said a few times but I am testing my new email
on the list and might as well put in my 2 cents. the first one bounced back so
I'm checking registration again) steve<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>Jeff,<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>Why not send DC back to the garage and set your Sunny boy there.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>By sending 350VDC back you will have considerably less voltage drop to
deal with than 240 VAC. There is no charge controller as it is AC coupled.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>I know the old SW4024 takes AC both ways on the AC in.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>I am doing a similar installation, AC coupled, but with outback VFX
instead of Xantrex.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>The outback will not backfeed the grid as it is an off grid inverter.
It has an internal transfer switch. The Aux relay has to be connected to a
relay to disconnect the sunny boy ac circuit to prevent of overcharging the
batteries as there is no charge controller. So yes the sb charges the
batteries and feeds the subpanel both.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>When the grid fails the sunny boy disconnects. After 5 minutes it will
see the ac from the outback battery backup and reconnect (thru the emergency
panel). Outback has an ac coupling paper on their website. I am not familiar
with the new xantrex's.<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>Steve<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>-----Original Message-----<br>
From: re-wrenches-bounces@lists.re-wrenches.org
[mailto:re-wrenches-bounces@lists.re-wrenches.org] On Behalf Of Jeff Yago<br>
Sent: Sunday, January 18, 2009 11:31 PM<br>
To: RE-wrenches<br>
Subject: Re: [RE-wrenches] Back feeding battery inverter with grid-tieinverter<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>I know this subject has come up before, but there have been several
different suggested ways to handle the problem and I was hoping for easiest.
We install lots of both on grid and off grid systems. However, we have a
client that will require a ground mounted array much futher away from the
inverter and batteries in the garage than we normally would want to do since
the voltage drop for this long distance would be excessive at low voltage even
with large cables. We have decided to locate a weather-proof sunnyboy grid-tie
inverter at the array, and supply 120/240 volts to the critical loads sub-panel
which is supplied by a Xanrex XW inverter and battery bank in the garage. I
realize there are several design issues here when the grid is down, since we
want the grid-tie inverter to remain on but be blocked from the grid by the
Xantrex inverter. <o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>The question is, what is the best way to keep a load on the sunnyboy
since it will not be grid connected during an outage. Also, is there a best
way to feed the output from the Sunnyboy to the Xantrex that does not just
power the sub-panel loads during an outage, but also will re-charge the battery
bank through the Xanrex?<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>If you back-feed the Xanrex from the sub-panel it is normally supplying
with output from the Sunnyboy, will the Xanrex see this input and think the
grid is up and be able to re-charge the battery bank?<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>Will we need any separate transfer switches or power relays?<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'><o:p> </o:p></span></font></p>
<p class=MsoPlainText><font size=2 face="Courier New"><span style='font-size:
10.0pt'>Jeff Yago<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span><o:p></o:p></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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