question

Hi, I have recently completed an ESS system which consists of the following:

1. 3x Multiplus II 10kVA – configured for 3 phase
2. 1x Fronius Symo 15kW 3phase connected on Multi output
3. 1x Victron RS MPPT 450/200
4. 1x Energy Meter – Grid
5. 1x Energy Meter – underfloor heating – connected before Multi
6. 1x Energy Meter – tank heater – connected before Multi
7. 6x BYD LV Flex Lite batteries
8. System is configured for ESS operation

The system works generally fine, but the following is of concern and is highly appreciated if this can be addresses in software updates.:

1. Only two energy meters can be connected to a single USB/RS485 converter. Why are only addresses 1 and 2 allowed for energy meter, while Modbus RTU allows for the connection of 247 devices.
2. The position of the AC load energy meter cannot be defined, i.e sitting before or behind the inverter. How does the Cerbo know where these are connected to to indicate correct current flow?
3. The dashboard indicates AC Load and Critical load. AC loads are highly unstable loads (readings are flucatuating between 0 and 1500W continously), although both non-essential circuits are switched off, no power consumption. Thus the AC load should indicate 0 W.
4. Fluctuation in values between AC load and Critical load. Although the critical load (output of Multiplus) is quite stable at 1 kW, considerable fluctuations are present. It seems that when the AC load reading increases, critical load tends to decrease.
5. When selecting under the advanced tab in VRM the critical load graph only L1 is displayed. L2 and L3 are nowhere to be found. Who determines that L1 is critical and L2 and L3 not? What is the difference between input and output of the critical load. Critical should always be behind the Multi and not on the input side.

Any workarounds for the above issues are highly appreciated to satisfy my client.

Regards,

E.