IF OFF grid is how you are sizing it, you might look at the Victron Quattro 5kW inverter. 100 A pass thru + AC assist, 45-65 hZ 90-140 input range. > On Apr 20, 2020, at 10:56 AM, Mac Lewis <[email protected]> wrote: > > This is an example of where some code requirements bump up against logic. I > believe the AC voltage will be quite usable at the site, just not for code > requirements of the AHJ, and it may get pretty low during high usage times. > They make the electrician size it for 100A minimum for an ADU, even though > the loads are pretty minimal, and then require <5% VD from the main service > entrance. That is the requirement for the certificate of occupancy. > > Luckily, off-grid buildings don't have these requirements at all. I'm > going to size it as an off-grid and probably tie it in at some point in the > future. > > Thanks for the input. > > On Sun, Apr 19, 2020 at 10:20 AM <[email protected] > <mailto:[email protected]>> wrote: > We had a similar situation, and are now feeding a battery bank with a pair of > 48 V Iota chargers. Iota can run on very low voltages. We have one Iota on > each leg of the the 120/240 split phase to balance the load. It works. > > --- > > > > On 2020-04-18 21:25, Ray wrote: > >> When doing the volt drop calculation, be sure to correct for temperature, >> per the note after table 8, chapter 9 of the NEC. The table values default >> at 167 deg F (75 C). An underground cable will be operating closer to earth >> temperature. When I run volt drop for a 4/0 copper cable at 60 deg F, I'm >> seeing that you could go over 60 amps and maintain a volt drop of 3%. >> >> Not sure what the requirements for the building are, but that exceeds most >> of my off grid systems. 60+ amps at a final voltage of 232 v is almost >> 14kW. Is there air conditioning? What are the calculated loads for this >> building? Is the inspector actually calling this a problem? >> >> I would do a proof of concept: turn every light on in the place, along with >> some typical appliances (hair dryer, microwave) hit a circular saw to really >> make the point, with a DMM plugged in. I found long ago that actual >> measured volt drop was not as bad as Chapter 9 first predicts. >> >> >> >> Ray Walters >> Remote Solar >> 303 505-8760 >> On 4/18/20 3:41 PM, Darryl Thayer wrote: >>> Hi Mac, There are a few questions like is it Al or Cu wire, What makes it >>> unusable? >>> for Voltage drop, I use Vd=2KIL/CMA for your case the unknown is the >>> current. The installation of an inverter with grid support. Many >>> inverters have this, you want a multimode inverter such as a Schneider, >>> Outback, SolArk and I could name at least 4 more. A normal house will run >>> on 30 amps. So assume 30 amps, Vd=2x21.6x30x1100/211600 =6.7 volts >>> So if the main house is at 240 Volts the remote house is at 233 Volts. The >>> multimode inverter could be set at grid support beyond 30 Amps. For higher >>> house loads the inverter can support up to 30 to 50 amps additional. >>> (SolArk is 50 amp) I would add a balancing transformer at the end of the >>> line to make the 120 loads balance. (an Autotransformer) such that 120 >>> volts loads are balanced and the load is shared between 240-Volt >>> conductors. Based on my customers' experiences I would use AGM LA >>> batteries, as I expect low usage of the battery and quick recharge, but >>> that is the customer's choice. I had one customer that had 10 years on the >>> float-AGM battery set. >>> >>> On Fri, Apr 17, 2020 at 8:15 AM Mac Lewis <[email protected] >>> <mailto:[email protected]>> wrote: >>> Hi wrenches, >>> >>> I've got a architect client with a sub-optimal power situation on one of >>> the projects he is working on. I'm running through a couple of scenarios >>> that may work. Its a ADU (accessory dwelling unit) that is about 1100' >>> from power. The farmer had taken it upon himself to bury some 4/0 a few >>> years ago to run power out there. Voltage drop is the big issue and its >>> not going to pass the AHJ inspection. We could just ditch the grid and go >>> off-grid, but it seems like a shame to not tap into the grid resource. >>> Instead of dealing with the voltage drop, I was thinking it may make sense >>> to rectify that low AC voltage input and parallel a smallish battery bank >>> (size is yet to be determined), then use an off-grid inverter to serve the >>> loads at good voltage. >>> >>> I am looking for feedback on this concept. What do you think? >>> >>> Also, are there any recommendations for good quality rectifiers with wide >>> input voltage window? >>> >>> Thanks in advance for your help >>> >>> -- >>> >>> >>> >>> Mac Lewis >>> >>> "Yo solo sé que no sé nada." -Sócrates >>> >>> _______________________________________________ >>> List sponsored by Redwood Alliance >>> >>> List Address: [email protected] >>> <mailto:[email protected]> >>> >>> Change listserver email address & settings: >>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>> <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> >>> >>> List-Archive: >>> http://www.mail-archive.com/[email protected]/maillist.html >>> <http://www.mail-archive.com/[email protected]/maillist.html> >>> >>> List rules & etiquette: >>> www.re-wrenches.org/etiquette.htm <http://www.re-wrenches.org/etiquette.htm> >>> >>> Check out or update participant bios: >>> www.members.re-wrenches.org <http://www.members.re-wrenches.org/> >>> >>> >>> >>> _______________________________________________ >>> List sponsored by Redwood Alliance >>> >>> List Address: [email protected] >>> <mailto:[email protected]> >>> >>> Change listserver email address & settings: >>> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >>> <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> >>> >>> List-Archive: >>> http://www.mail-archive.com/[email protected]/maillist.html >>> <http://www.mail-archive.com/[email protected]/maillist.html> >>> >>> List rules & etiquette: >>> www.re-wrenches.org/etiquette.htm <http://www.re-wrenches.org/etiquette.htm> >>> >>> Check out or update participant bios: >>> www.members.re-wrenches.org <http://www.members.re-wrenches.org/> >>> >> >> _______________________________________________ >> List sponsored by Redwood Alliance >> >> List Address: [email protected] >> <mailto:[email protected]> >> >> Change listserver email address & settings: >> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org >> <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> >> >> List-Archive: >> http://www.mail-archive.com/[email protected]/maillist.html >> <http://www.mail-archive.com/[email protected]/maillist.html> >> >> List rules & etiquette: >> www.re-wrenches.org/etiquette.htm <http://www.re-wrenches.org/etiquette.htm> >> >> Check out or update participant bios: >> www.members.re-wrenches.org <http://www.members.re-wrenches.org/> >> > _______________________________________________ > List sponsored by Redwood Alliance > > List Address: [email protected] > <mailto:[email protected]> > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> > > List-Archive: > http://www.mail-archive.com/[email protected]/maillist.html > <http://www.mail-archive.com/[email protected]/maillist.html> > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm <http://www.re-wrenches.org/etiquette.htm> > > Check out or update participant bios: > www.members.re-wrenches.org <http://www.members.re-wrenches.org/> > > > > -- > > > > Mac Lewis > > "Yo solo sé que no sé nada." -Sócrates > > _______________________________________________ > List sponsored by Redwood Alliance > > List Address: [email protected] > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > List-Archive: > http://www.mail-archive.com/[email protected]/maillist.html > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > www.members.re-wrenches.org >
> [email protected] > <blocked::mailto:[email protected]%22%20%5Co%20%22blocked::mailto:[email protected]> > www.SWNL.net > <blocked::http://www.swnl.net/%22%20%5Co%20%22blocked::http://www.swnl.net/> > Solarwinds Northernlights > Serving Mid Coast Maine & Northern California > 207-832-7574 Cl. 610-517-8401 > > Blair "TUMP" May > ******** MAINE'S CHARTER ******** > NABCEP "Certified PV Installer" > > ******** MAINE'S CHARTER ******** > Trace Xantrex "Certified" Dealer / Installer" >
_______________________________________________ List sponsored by Redwood Alliance List Address: [email protected] Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/[email protected]/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
