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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Jeff, <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I had this same hesitation when we first
fired up our AC coupled system. When speaking with Steve at outback and he was
pretty sure that the generator would put out dirty enough power that the
Fronius inverter would not like it and shut down. He was correct—it goes into
an error mode as soon as the geni kicks on. Once the generator shuts down the
Fronius senses the frequency is back within range and resets itself. Turned
out to be a simple solution and has been operating flawlessly for almost a year
now.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Good luck!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 color=navy face="Times New Roman"><span
style='font-size:12.0pt;color:navy'>Mark Dickson<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=navy face="Times New Roman"><span
style='font-size:12.0pt;color:navy'>Oasis Montana Inc.<o:p></o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
re-wrenches-bounces@lists.re-wrenches.org [mailto:re-wrenches-bounces@lists.re-wrenches.org]
<b><span style='font-weight:bold'>On Behalf Of </span></b>Jeff Yago<br>
<b><span style='font-weight:bold'>Sent:</span></b> Tuesday, July 28, 2009 6:55
AM<br>
<b><span style='font-weight:bold'>To:</span></b> RE-wrenches<br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [RE-wrenches] AC
coupled with grid and backup generator</span></font><o:p></o:p></p>
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<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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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><br>
We are completing a residential 4 kW solar system that is on the grid, but has
backup battery-powered Xantrex 6 kW inverter, AC coupled Sunny-Boy inverter,
and a 17 kW Kohler generator. The larger generator is to allow operation
of a ground-source heat pump during winter which is not supplied from
the inverter fed panel. We have added a relay cut-out for the Sunny
Boy AC output to prevent over-charging the batteries during utility outage, but
have some concerns about back-feeding the generator through the 100 amp 240 VAC
transfer switch when the Sunny Boy thinks the grid is still up. <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Will the Sunny Boy try to couple to the generator like it
will the inverter which will be feeding other house loads during an outage and
if so, any risk? We have wired an aux. switch contact on the
transfer switch to also lock out the Sunny Boy output using the same relay
control as being used for high battery voltage cutout, but this is adding other
issues related to needing multiple relays due to different relay coil voltages.
<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Anyone smoked a large generator by back-feeding from
inverter when the loads are reduced or shut off?<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks,<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Jeff yago<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><br>
<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Netscape. Just the Net You Need.<o:p></o:p></span></font></p>
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