We are trying to integrate our system containing multiple Solar Charge Controllers using Mod-Bus but are having some issues.
On the Mod-Bus codes for the PV chargers there is a note on register 776/777 saying it won’t work for multiple solar chargers.
Can Victron provide the registers for additional solar chargers or is there an overall value register where we can pull the total PV Voltage & Current or Total Power ?
Using register 789 PV Power only gives the power for one of the 3 solar chargers.
If you have multiple solar charge controllers, in Services - Modbus TCP - Available services, don’t you have multiple unit IDs, one for each solar charger?
Or is a single one that aggregates all?
The modbus server is a function of the Venus OS - so there is only the one UID.
However, the issue of the modbus registers only reflecting ONE of the solar chargers connected is something that does need to be addressed in a future version of Venus OS. This either needs to reflect the sum of all solar chargers, or to have a lot more space allocated to the Modbus map. I have heard of instances of up to seven solar chargers connected on one system. My proprietary BMS management code will allow for three chargers in its map.