<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><DIV>I hope i do not muddy the water here. if you have 3 phase delta, usually the single phase transformer is larger, can you do the solar in split phase? </DIV>
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<DIV>Also staying with the 3 phase, why not use a three pole service rated switch to Line side tap, and use two poles for the single phase and the third pole for the high leg. After the 3 pole switch, use a 2 pole switch for the wind turbine (breaker in a box) , and a three pole sw in a box for the 3 phase solar. . <BR></DIV>
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<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> John Wadley <wadleyjk@hotmail.com><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> RE-wrenches <re-wrenches@lists.re-wrenches.org><BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Wed, March 2, 2011 3:36:19 PM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> [RE-wrenches] One renewable disconnect.<BR></FONT><BR>
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Wrenches,<BR> I am designing a system with both wind and solar backfeed and I'm having an issue with the utility. They say we need to have a single renewable disconnect switch before the grid backfeed. The solar is designed to backfeed 3-phase through a meter, then a fused AC disconnect to the line-side to avoid upsizing the MDP. The wind inverter output is 120/240V split-phase (10A) which I had planned to do load-side backfeed through a wind meter with a seperate AC disconnect since it was so small. To meet the single renewable disconnect requirement, I'm thinking I may need to backfeed the wind on the load-side to one of the three phases. I guess my question is can I use a single 5 pole fused AC disconnect to control both with one switch handle or is that an NEC violation wrt to merging separate systems within the same conduit? Or, should I keep them in separate switch boxes with some
kind of gang handle? I have a 3-phase aggregation panel for the solar inverters (6 total, 2 per phase, 240 delta), but if I integrate the wind there in order to simplify the AC disconnect issue, the solar meter will register both solar and wind production. What is the best practice in this situation?<BR><BR>Thanks,<BR>John Wadley, MSEE, PE<BR>NABCEP Certified Solar PV Installer (TM)<BR>Wadley Engineering<BR>214-557-3841<BR><BR>CONFIDENTIALITY: This communication, including attachments, is for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, any use, copying, disclosure, or distribution or the taking of any action in reliance upon this information is strictly prohibited. If you are not the intended recipient, please notify the sender immediately and delete this communication and destroy all copies.<BR><BR></DIV></DIV></div><br>
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