Bruce: There has been some correspondence here on boot-strapping low SOC lithium batteries in protect mode. Buying an outboard battery charger seems hard to accept when you are standing next to a sophisticated battery charger.
We had a few occasions of a large E-vault system shutting down for low charge due to mis calibration of SOC. We restarted the system by disconnecting the closed loop data connection, reprogramming the inverters to think they were operating with a VRLA bank and restarting the system. The battery bank, when restarted came on line just long enough to accept battery charging. Once the SOC came up to acceptable levels we reset the system for a BMS battery and we were back running. Maybe this procedure might work for someone else. I have a step-by-step for doing this with a Sunny Island system if anyone wants to look it over. William Miller Miller Solar.com 805-438-5600 www.millersolar.com On Wed, Dec 11, 2024 at 11:08 AM Bruce Erickson via RE-wrenches < re-wrenches@lists.re-wrenches.org> wrote: > Recently one of our four now-orphaned SunVault systems failed to back up > for our customer. On site we found the batteries discharged below cut-in > voltage for unknown reasons (no more monitoring, no more tech support). > Even though it had been sunny for a few days the system failed to retain a > reserve to restart once sun returned. I’m looking for recommendations for > 48 volt external chargers for this situation. We’re looking at Iota which > only has a 13 amp charger at 48v but does have a plug-in module for > controlling LiFePo charging. At 256 amphours of parallel batteries > hopefully an 8 or 10 hour charge would get us up to cut-in. I’m also not > sure how the Iota will play with any BMS the SunPower batteries might have. > Any recommendations for this situation would be much appreciated. > > Thanks in advance, > Bruce > > Bruce Erickson > Mendocino Solar Service > 707-937-1701 > PO Box 1252 > Mendocino, CA 95460 > > > > "Serving the Solar System" > > > > > > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > http://www.members.re-wrenches.org > >
_______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://www.members.re-wrenches.org
