Hi all,
I have a Multi_RS and a Fronius coupled on AC. I also have a GX (Rpi) that controls the MultiRS and talks to Fronius over Modbu/TCP. Battery also connected into the Rpi over serial.
Configuration is working relatively good and I wanted to know if the frequency shifting is really necessary.
Couldn’t Fronius be controlled through Modbus to reduce its generated power? I’m guessing the MultiRS shifts frequency automatically whenever it detects an AC generator on it’s output…
Thank you.
Usually when you are not conected to grid near the top of the battery charge it does this.
I have a node red flow that uses the power limit of the fronius to try minimise the frequency shift. So natively -no- frequency shift is inbuilt cant be overridden.
OK,
Thank you for the clarification.
I’m most of the time off-grid and the batteries are full (a lot of sun in the summer:)
The reason I’ve asked about this is because the system tends to oscillate when the batteries are full and there’s not enough load. The batteries get charged and discharged around the floating voltage (53.6V). Maybe the frequency correction is too severe and that’s the problem…
It sort of has to be to prevent overshoot and battery damage.
The oscilation is irritating. That was how my explorations into a node red experiment began.
I think there aresome settings in the fronius that can be adjusted, but in some cases using its own meter can be easier.
I have a smart meter that’s compatible with the Fronius. You’re saying that if I install it on the output of the Victron and limit the production in the Fronius based on the house consumption, it might work?
I might try that sometime if it makes sense.
Also, another thing is that I’m using the “dbus-serialbattery” driver and I have a feeling that something can be improved in there (in the config) so that the charging current is gradually increased/decreased, avoiding this oscillation when battery is floating. That would be the first step trying to solve this…
Batteries usually use two methods for control.
Cvl and ccl.
If you create tour own control for that then it will.
I was thinking the fronius meter, since it by nature talks to the fronius, if you are not inclined to experiment.