Re: [RE-wrenches] Interconnection downstream of ATS

[Allan Sindelar]

Title: Interconnection downstream of ATS

Just musing here, Mark, What if the coil of the contactor was energized by the grid. The benefit is that grid goes down and so does theinverter; grid goes up and the inverter waits 5 min, long enough for the ATS to transfer back to grid. I can see two downsides: 1) the continuous tiny load of the contactor coil, and 2) you would have to run signal cable from the grid point on the ATS (or ahead of it) to the contactor at the inverter.'s point of connection to AC. Allan Sindelar Allan@positiveenergysolar.com NABCEP Certified Photovoltaic Installer EE98J Journeyman Electrician Positive Energy, Inc. 3201 Calle Marie Santa Fe, New Mexico 87507 505 424-1112 www.positiveenergysolar.com On 9/26/2010 1:31 PM, Mark Frye wrote: Folks, 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. 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. I am wondering about the following 4 considerations: 1 - Code / AHJ acceptablity: Does the Code address the issue of load side connection downstream of an ATS? 2 - Utility (PG&E) acceptability: I don't see how the utility would care. 3 - Inverter manufacturer acceptability: The manufacturer might not warrant this application unless they were confortable that the inverter never sees generator voltage. 4 - Functional efficacy: Owner would have to reset inverters manually. Has anyone worked throught this scenario?   Mark Frye Berkeley Solar Electric Systems 303 Redbud Way Nevada City,  CA 95959 (530) 401-8024 www.berkeleysolar.com  _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org

_______________________________________________
List sponsored by Home Power magazine

List Address: RE-wrenches@lists.re-wrenches.org

Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out participant bios:
www.members.re-wrenches.org