bulraydin avatar image
bulraydin asked

Cerbo mixing up measurements , Fronius continuously throttling

Hello everyone,

we have a special case, where I could not find any answer in the community, hence decided to write here , maybe somebody has a solution.

Following is the setup :

1. 12 x Quattro 48/15000

2. 6 x Fronius Eco 27.0

3. 4 x Smartsolar 450/100

4. 500kWh Pylontech batteries (US3000 )

5. Cerbo GX + Touchscreen

Fronius inverters are connected to AC-Out 1

Grid is connected to AC-In 1

Communication of Cerbo and Fronius are over LAN

All firmware is updated,

ESS asisstants are loaded to all the inverters. Grid can only give 100A per phase, hence on quattro's also the input current is limited to 20A each, to avoid overload on the grid.

System works fine during off-grid (when grid is shut down)

as soon as grid is connected and the power generated by Fronius exceeds the power requested by the loads, cerbo starts mixing up data. For example it suddenly shows no loads at the output for a few seconds and this causes him to send the command to Fronius inverters to step down with the production , although in reality the loads are more or less constant and battery not yet full.

This problem repeats itself as long as the PV generation is higher than the loads. Fronius inverters try to ramp up but then they are throttled due to false measurements. This is quite unhealthy and very inefficient.

Currently I have disabled ESS , instead I have uploaded the PV Inverter Support and the general flags for AC ignore assistants , however this is not a good solution , as the customer would like to set the SOC levels himself.

What could be the reasons ? Where does cerbo get the measurement data from ? Could the cerbo be defected or somehow slow in reaction / calculation ? or problem somewhere else ?

Would appreciate your comments very much.

Best Regards

cerbo gxFroniusAC PV Coupling
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

0 Answers