<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div>You can't go wrong with a new "solar-ready" service panel. You can tell the customer that, in addition to enabling a larger solar system, it is a safety upgrade.</div><div><br></div><div>Otherwise you're going to have to backfeed one of these subpanels or the one of the 100A mains inside the house.</div><div><br></div><div>Do the mains in #2 have their own breakers, or are they pass-through lugs? Or one of each (which is what I've commonly seen before). As I've argued previously, if there's a main C/B on both these points, that isolates the 200A main disconnect and the load-side feeder from it. If both of the "mains" are 100A busses with 100A main C/Bs, then you can only backfeed 20A on each (even if you're tying in on one of the other subpanels). Which would would limit you to 40A overall for the system -- less than the 60A
you want. If one of the "mains" is a pass-through lug, then that moves the problem to the subpanel that it is feeding.<br></div><div><br></div><div>Jeffrey Q.</div><div><br></div> <div style="font-size: 12pt; font-family: 'times new roman', 'new york', times, serif; "> <div style="font-size: 12pt; font-family: 'times new roman', 'new york', times, serif; "> <font size="2" face="Arial"> <hr size="1"> <b><span style="font-weight:bold;">From:</span></b> Pekka Laine <pekka@photonsolarpower.com><br> <b><span style="font-weight: bold;">To:</span></b> re-wrenches@lists.re-wrenches.org <br> <b><span style="font-weight: bold;">Sent:</span></b> Sunday, December 25, 2011 1:46 AM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [RE-wrenches] Landing into a sub-panel without a main service<br> </font> <br>
Thank you for all the great interest and the comments on this topic. Here are some more details on this project:<br> <br>1. 200 A fused Zinsco Main Switch at the service entrance (45 years old) <br>2. Inside the house Square D Split-bus "Main" panel with two 100 “Mains” fed by 1/0 wire from the outside 200A Main fused switch<br>3. Next to it Murray 100/125A Sub-panel (Newer, some damage) <br>4. Outside Zinsco 125A Sub-panel <br>5. In the pool room 125A Sub-panel <br>6. In the garage Murray 125 A Sub-panel (newer, looks OK) <br><br>The utility is SDG&E, so no line or load side taps are usually allowed. On another project, we have previously replaced a similar type fused main switch with a Eaton Solar Ready Loadcenter with 225A rated buss and 200A main breaker in order to be able to backfeed max. 70 A of PV. I am leaning towards doing the same on this one....<br><br>In this case, I will recommend the customer to upgrade/replace the old Square
D split bus panel and items 3 & 4. as well. Any other suggestions are welcome.<br><br>Happy Holidays!<br><br>Pekka Laine<br><br>President<br>Photon Solar Power Inc.<br><a target="_blank" href="http://www.PhotonSolarPower.com">www.PhotonSolarPower.com</a><br>Cell. 760-556-8170<br>Toll Free 888-SUN-ACDC<br>CA Lic. #933648<br>NABCEP Certified PV Installer # 032611-174<br><br>_______________________________________________<br>List sponsored by Home Power magazine<br><br>List Address: <a ymailto="mailto:RE-wrenches@lists.re-wrenches.org" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br><br>Options & settings:<br>http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org<br><br>List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org<br><br>List rules & etiquette:<br><a target="_blank"
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