8H00 in the morning with low loads on a Sunday, dont want to know where this system will peak.
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You are rightā¦what you term low loadsā¦i cant imagine the peak loads!
Average load on a normal work day is around 18kwh over the 3 phases.
- Seems very low - you should get about 150kwh per day from the solar on this system?
We are aiming for 190kwh per day, or that was roughly the design, we are sitting at the halve way mark currently and below is the results.
We are pushing back to see what we can generate. Were worried that the Meter might go into tamper mode, but so far we are okay.
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A beast ā¦ 
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Why isnāt the MPPT pushing back and only the Fronius?
Insane system! A man can dream. 
The MPPT stops working when the batteries reach 100%. Battery volts needs to drop a little before it will start again.
End of day figures, the system did not reach the expected 190kwh, but as can be seen from the info below, there were a few cloudy patches that reduced the production.
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Ah okay, so the MPPT and Fronius cannot be used at the same time to feed the grid? Presumably the MPPT would be able to feed back when the batteries are full also?
Of course they can. The default settings (when you first put a GX into production) is to feed in AC-coupled PV but to not feed-in DC-coupled PV. At this specific site, an oversight left modbus-tcp disabled on the Fronius which meant they could not be limited, and as a result they fed all their energy into the grid. Jaco used this as an opportunity to sommer check what it can doā¦ 
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Did you enabled feedback on excess DC under the ESS menu?
No we did not, I did not plan to feed back, I actually forgot to switch the Modbus on in the Fronius settings and went home for the weekend, the Victrons could not control the Fronius and we could not prevent the feedback. We decided to leave it like that as this was the perfect opportunity to see what the system could produce. I have completed the Fronius config yesterday and stopped the feedback.
Iām in process of assisting someone with an oldāish 5kwSMA/5kVAVictron installation. Existing does not have GX, has Outback MPPT and 24x2V flooded battery bank. The thinking is to add protection, add Cerbo, upsize Victron to 10kVA (and move 5kVA to holiday home), connect SMA onto Victron AC-out1, keep/replace Outback(?), install Li-Ion batteries. The parts Iām trying to get my head around is the SMA integration and the options wrt the Outbackā¦ From GX - Monitoring SMA PV Inverters its clear GX can monitor but not control the SMA which is problematic when grid available because canāt feed-in and Victron canāt freq shift to controlā¦Iāve considered (crude) workarounds such as contactor controlled by Victron Prog Relay disconnecting SMA when Victron SOC reaches (say) 85% and connecting again when dropped to 75%ā¦ Anyone come across more elegant solutions e.g. Victron prog relay connection to SMA that causes same to shut down or reduce productionā¦know Victron reasonably well but not SMA? The next challenge is the Outback - keep or chuck?
The SMA inverters, at least the older ones, are a bit weird. They donāt allow you to control them via sunspec/modbus unless you apply for a āgrid codeā (some kind of password system). When you send this password to the inverter, it enables writing a whole heap of additional registers, one of them being the register needed to do a grid limit.
But this grid code/password needs to be sent to the PV-inverter every time you need to unlock it, so adding that to the dbus-fronius driver is not really something we want to do. Ideally we want something that has generic sunspec support.
Now it is possible that some of the newer inverters do support this, but I donāt know. I have never had the opportunity to look.
So simplyā¦ I donāt know.
Howeverā¦ there is a guy who has done it. He made SMA support for the older inverters. The github repo is here. Itās just that all the grid-code stuff, though it can be made to work, is terribly SMA-specific, and it is unclear whether it is even needed for the newer PV-inverters.
Thanks at @plonkster for reply and good info. From scanning this seems SunSpec in place for newer SMAās and might be possible to upgrade some of older ones with new comms cardā¦ Iāll investigate that one bit furtherā¦
honestly I would dump the outback and get a smartsolar in there. Your data / efficiency will be more complete and happy blue.
With regards to the SMA, you could always using an assistant / general flag to drop the ac input until a certain battery percentage. Or like you send us a contactor to drop out grid using one of the victron relays. Otherwise if this SMA has a connect module you would have to buy an expensive home manager to allow the SMA to self regulate when there is grid and if I am not mistaken there is a 50hz island grid you choose that allow frequency shifting off-grid.
Does the Fronius need their R7000 data manager add-on to implement the SunSpec modbus feedback?
Only the older models. I believe all models now have it fully integrated.
Yup. Right, said Fred. Newer models have the card already in the expansion slot. Older ones (or larger setups where you have multiple PV-inverters and a single datamanager) needs it as an extra.
Fronius has something called Solar.NET which is the protocol between the PV inverter and the datamanager. Itās their internal little thing. The DataManager translates that to something the outside world can understand. In my experience, you best want to cap it at 4-PV inverters per datamanger (they get really slow after that).
But none of this matter to the ordinary guy who wants to install a single unit at his house 
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