Original question
Scenario:
- Multiplus2 in ESS mode
- MPPT
- Cerbo GX
During sunny days, the battery is heavily loaded by the Multiplus2 which is not what I want. The solar modules of the MPPT are delivering enough energy during the day to load the battery so that the other PV inverter can feed in to the public grid and earn $.
In the Cerbo GX setting in the device Multiplus2 there is a setting ‘switch’ to set the device in inverting only but this does not really work - it stops charging but blocks inverting, too
[ – a lot of other thread post - see original discussion in old forum – ]
I have implemented it in Node Red by setting the DVCC Max Charge Current to the Amps the MPPT delivers (+50W). Together with the forecast.solar and some safety functions (JK BMS max voltage and battery temperature). In case of bad whether conditions the Multiplus2 is used, too. Works pretty good.
[ – the question to share the flow was posted – ]
Answer
If you are interested, I have created a node red flow, which is available here:
https://flows.nodered.org/flow/39c15e43f615bd8a98e03eb79801784e
What is does:
This flow grabs the forecast.solar data, calculates some data and adjusts the Max Charge Current of the Victron Cerbo with the goal, to charge the battery mainly with the Victron Solarcharger, if possible.
The Max Charge Current is additionally limited, in case of high JK BMS temperature, high voltage, reaching absorption voltage, maximum cell voltage.
The limits can be adjusted the flows environment variables page.
The flow can be easily adapted if another BMS is used or other requirements must be taken into account.
IMPORTANT: Use this Node-RED flow at your own risk; no warranty or liability is provided.