Hi,
Having a problem with Fronius Symo ramping up output as soon as the grid returns but before the Victron cluster has reconnected to the grid. The inverter cluster tries to direct the excess power from the Fronius to the batteries, but the batteries are full. This leads to overvoltage on the battery, and correctly the battery protects itself. This problem occurs in the time window between grid being restored and the delay before the cluster re-connects to the grid.
SYSTEM SETUP
- All devices have latest firmware.
- Fronius settings are as per guidance.
- MODBUS control is working and top priority.
- FSPC does work, See the chart
- EM530 grid meter
CHART ILLUSTRATING THE PROBLEM
In the chart below:
- The thin black line is Output Frequency and should be Red, (suspect a VRM bug).
- As soon as Grid returns the inverter drop their frequency to the grid frequency. (expected)
- The Fronius power ramps up under FSPC. (Thick black line)
- Battery is full, cluster can be seen pushing energy into the battery and the battery voltage rising leading to the battery protection kicking-in.