[RE-wrenches] Dual radian system stopping selling on sunny days

jay jay.peltz at gmail.com
Fri Oct 3 13:22:12 PDT 2025 

I haven’t done many grid connected systems so I can’t tell you if float coordination is valuable or not, for off grid it is, as its kinda impossible to get multiple controllers synchronized  and its hard to see how float coordination would impact the issue you had.  

Auto change termination I don’t use, as it relies on the FNDC which will get off in its counting and it then stops the charge usually too soon which starts a whole list of failures soon to happen. That could definitely have been an issue.  

As to his comments about outback, agreed they will have to do some amazing proving before I use them again.

jay



> On Oct 3, 2025, at 9:52 AM, Dave Tedeyan via RE-wrenches <re-wrenches at lists.re-wrenches.org> wrote:
> 
> Here is a minor update. We got the Mate3 firmware updated. I also got a call back from Chris at tech support. He suggested that I disable Float Coordination and Auto Charge Termination Control in the Mate3. Since these changes, the issue has not happened. Although last year, the issue did not happen after this date either, even though we have been having some very clear sunny days. I have also not seen the battery SOC go from 99% to 100%. I am not sure if this means that the issue is fixed, or whether it would not have occurred at this point even if I did nothing. So I might have to wait until next year to know for sure. 
> 
> It was good to hear from Chris though, who has been there for something like 11 years. It sounds like they lost all their salesforce and customer information in the buyout, but I know that Chris knows his stuff when it comes to the Outback equipment. According to him, things are promising to get the old Outback style equipment back and available. Although, personally, they are going to have to prove themselves before I fully trust them, just like any new manufacturer.
> 
> Cheers, 
> Dave
> 
> On Sat, Sep 27, 2025 at 9:16 AM Maverick Brown via RE-wrenches <re-wrenches at lists.re-wrenches.org <mailto:re-wrenches at lists.re-wrenches.org>> wrote:
>> Great! 
>> 
>> I was driving yesterday, and couldn’t find this document. 
>> 
>> I had this issue pop up on a dual stack and found out the inverter charger had been turned off. Turned it back on via the Charger button on the MATE3S and BAM! Offset changed to Selling. 
>> 
>> I set:
>> SellRE = 53.6
>> CC.FLT = 54.4
>> CC.ABS = 55.2
>> 
>> I measure these at the battery and make adjustments (either in calibration settings or by changing the above numbers).
>> 
>> Thank you,
>> 
>> Maverick
>> 
>> Maverick Brown
>> Off-Grid Solar Commander since 2006
>> Maverick Solar Enterprises, Inc.
>>  • Solar Commander Remote Power
>>  • SunFlow Systems Cathodic Protection 
>> maverick at mavericksolar.com <mailto:maverick at mavericksolar.com>
>> 512-460-9825
>> 
>> 
>> 
>>> On Sep 26, 2025, at 10:40 PM, Tyrone Houck via RE-wrenches <re-wrenches at lists.re-wrenches.org <mailto:re-wrenches at lists.re-wrenches.org>> wrote:
>>> 
>>> 
>>> It's also worth considering temperature compensation and how that may affect the dynamic...also the CCs float and absorb should be set slightly higher than the inverters. Regarding offset behavior, here is an application note that may help..
>>> 
>>> https://outbackpower.com/downloads/documents/appnotes/offset_tech_note_correc.pdf
>>> 
>>> 
>>>    
>>> 
>>> On Fri, Sep 26, 2025, 8:23 PM Tyrone Houck <tyronehouck at gmail.com <mailto:tyronehouck at gmail.com>> wrote:
>>>> Forgive me if I'm missing something but typically I would have sell voltage slightly higher than float and lower than absorb.. I also never use the FNDC for charge termination and instead let the charge controller do everything by voltage... this may be a slightly different logic for lifepo4 but has always worked great for me for lead acid and agms.
>>>> Best of luck!
>>>>    
>>>> 
>>>> On Fri, Sep 26, 2025, 10:52 AM Dave Tedeyan via RE-wrenches <re-wrenches at lists.re-wrenches.org <mailto:re-wrenches at lists.re-wrenches.org>> wrote:
>>>>> To the Outback extraordinaires,
>>>>> 
>>>>> I've got a dual radian, grid tied system that has been in service for about 9 years. Recently, it has started this behavior where it will stop selling to the grid on sunny days. Looking back at the data, this has happened intermittently and very infrequently a couple years ago. But now we are at the point where it happens every sunny day. Once the batteries get up to fully 100% charged (not 99%), the selling stops and the system only harvests enough solar to cover the backed up loads. 
>>>>> 
>>>>> I got a hold of the USB card data. It appears that the inverter goes from "Sell Enabled" to "Offset" when this happens. I cannot tell whether the inverter randomly decides to switch mode and then stop selling, or whether it is the stopping selling that puts it in "Offset" mode. The sell voltage is set at 52V, and float is set to 54.4V. It looks like the batteries are generally sitting around 54V when this happens. Once the inverter enters "offset" mode, then the battery voltage stays steady at 54.0V
>>>>> 
>>>>> Does anyone have any idea what can be causing this to happen?
>>>>> Cheers,
>>>>> Dave 
>>>>> 
>>>>> --
>>>>> 
>>>>>  <https://www.sungineersolar.com/>	
>>>>> Dave Tedeyan, P.E.
>>>>> Owner | Sungineer Solar
>>>>> p: he | him | his
>>>>> a: 1653 Slaterville Rd. <https://www.google.com/maps/search/1653+Slaterville+Rd.+%C2%A0+%7C%C2%A0Ithaca,+NY+14850?entry=gmail&source=g>  <https://www.google.com/maps/search/1653+Slaterville+Rd.+%C2%A0+%7C%C2%A0Ithaca,+NY+14850?entry=gmail&source=g>| Ithaca, NY 14850 <https://www.google.com/maps/search/1653+Slaterville+Rd.+%C2%A0+%7C%C2%A0Ithaca,+NY+14850?entry=gmail&source=g>
>>>>> w: www.sungineersolar.com <http://www.sungineersolar.com/>
>>>>> c: (607) 270-0370
>>>>> _______________________________________________
>>>>> List sponsored by Redwood Alliance
>>>>> 
>>>>> Pay optional member dues here: http://re-wrenches.org <http://re-wrenches.org/>
>>>>> 
>>>>> List Address: RE-wrenches at lists.re-wrenches.org <mailto:RE-wrenches at 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 <http://www.members.re-wrenches.org/>
>>>>> 
>>> _______________________________________________
>>> List sponsored by Redwood Alliance
>>> 
>>> Pay optional member dues here: http://re-wrenches.org <http://re-wrenches.org/>
>>> 
>>> List Address: RE-wrenches at lists.re-wrenches.org <mailto:RE-wrenches at 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 <http://www.members.re-wrenches.org/>
>>> 
>> _______________________________________________
>> List sponsored by Redwood Alliance
>> 
>> Pay optional member dues here: http://re-wrenches.org <http://re-wrenches.org/>
>> 
>> List Address: RE-wrenches at lists.re-wrenches.org <mailto:RE-wrenches at 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 <http://www.members.re-wrenches.org/>
>> 
> _______________________________________________
> List sponsored by Redwood Alliance
> 
> Pay optional member dues here: http://re-wrenches.org
> 
> List Address: RE-wrenches at 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
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20251003/e2562547/attachment.htm>

More information about the RE-wrenches mailing list