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<P><FONT SIZE=2 FACE="Arial">Folks,</FONT>
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<P><FONT SIZE=2 FACE="Arial">I am looking at doing a standard grid-dependent PV installation. The only catch is that the whole house is backed up by a generator with automatic tranfer switch.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">Due to the layout of the various equipment, it would be a whole lot easier to interconnect the PV at a point downstream of the ATS. Because the ATS takes a minute or so to bring the generator up and transfer, the inverter would drop out when the line is lost. If I had a contactor on inverter output, with the coil held by line voltage and a reset switch, I could set it up so that the inverter output would be isolated from the generator upon line voltage loss, and manually reset once utility line voltage was restored.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I am wondering about the following 4 considerations:</FONT>
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<P><FONT SIZE=2 FACE="Arial">1 - Code / AHJ acceptablity: Does the Code address the issue of load side connection downstream of an ATS?</FONT>
<BR><FONT SIZE=2 FACE="Arial">2 - Utility (PG&E) acceptability: I don't see how the utility would care.</FONT>
<BR><FONT SIZE=2 FACE="Arial">3 - Inverter manufacturer acceptability: The manufacturer might not warrant this application unless they were confortable that the inverter never sees generator voltage.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">4 - Functional efficacy: Owner would have to reset inverters manually.</FONT>
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<P><FONT SIZE=2 FACE="Arial">Has anyone worked throught this scenario?</FONT>
<BR><FONT FACE="Arial"> </FONT>
<BR><FONT SIZE=2 FACE="Arial">Mark Frye</FONT>
<BR><FONT SIZE=2 FACE="Arial">Berkeley Solar Electric Systems</FONT>
<BR><FONT SIZE=2 FACE="Arial">303 Redbud Way</FONT>
<BR><FONT SIZE=2 FACE="Arial">Nevada City, CA 95959</FONT>
<BR><FONT SIZE=2 FACE="Arial">(530) 401-8024</FONT>
<BR><A HREF="http://www.berkeleysolar.com"><U><FONT COLOR="#0000FF" SIZE=2 FACE="Arial">www.berkeleysolar.com</FONT></U></A><FONT SIZE=2 FACE="Arial"> </FONT>
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