Hi Larry,
I am curious why you would use the 100Hr rate for this approximation and not the 20 or 24Hr one, since that is the period in which Mac is reporting the anomaly. Happy to learn the details! Thanks, Glenn From: RE-wrenches <re-wrenches-boun...@lists.re-wrenches.org> On Behalf Of Starlight Solar Power Systems Sent: Friday, April 19, 2019 3:10 PM To: RE-wrenches <re-wrenches@lists.re-wrenches.org> Subject: Re: [RE-wrenches] Operating Voltages Outback RE High Capacity Battery Mac, Only removing 6kWh from 46kWh of storage should not be able to produce the voltage sag to trigger AGS. That’s only about 13% at a 100Hr rate. Voltage should be no where near that point. Have you verified actual voltage when the AGS is triggered? Loose wiring or terminal corrosion can cause voltage drop but I would think that an easy find/repair you would have checked. Saying the battery easily charges to 100% worries me as sulfated batteries do that. Healthy LA batteries take many hours to reach full saturation. Has cell voltage been compared for non-uniformity? Has the equalization charge been performed? I am not a fan of the unusual low voltages that Outback prescribes for EnergyCells and seriously wonder how these voltages can properly maintain these cells. CV is below the point where balanced O2 and H2 evolution takes place. But, thats off point. Larry Crutcher Starlight Solar Power Systems On Apr 19, 2019, at 10:27 AM, Mac Lewis <maclew...@gmail.com <mailto:maclew...@gmail.com> > wrote: Hello Wrenches, We recently inherited an Outback system that I've been keeping an eye on via Optics. Its a dual stack 3648 VFXR, with about 4kW of PV with a single string of EnergyCell 1100RE battery bank (reported to be ~6 months old) ~.46 kWh at C20. I have been observing how the system functions and how the voltage behaves. We keep getting 2 minute voltage starts on the generator in the middle of the night that don't seem necessary judging from how much energy has been used from the battery bank. I am hesitant to tweak anything because these battery set-points are a bit different than I'm used to. As per Outback: Absorb Voltage is 55.6V for 2 hours Float Voltage is 54.0V I've slowly been dropping the 2 minute start voltage to see if there is a bottom, but I'm hesitant to take it much lower (maybe I should). 2 minute start voltage: 44.8 V. The system easily charges the battery bank to 100% (and easily reached the 2 hr absorb time) every day. The flexnet DC is correctly set up and calibrated. The load on the system is pretty consistent. They use between 400 and 600W throughout the night. An average night, they may use about 6 kWh before the voltage sags below the 2 minute start voltage and it starts the generator. Just curious if our 2 minute voltage needs to be dropped or if these batteries are degraded. What corrective changes can I make to get better performance? I have and will call Outback about this, but I'd like other perspectives as well. Thanks as always for your expertise -- Mac Lewis "Yo solo sé que no sé nada." -Sócrates _______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org <mailto:RE-wrenches@lists.re-wrenches.org> Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/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>
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