I read in the release notes of v3.66 that the connection to SolarEdge inverters has improved.
I see no such thing : I have 2 SE inverters connected, one 3-phase, one mono-phase.
I see them appear and disappear all the time both from the console as from vrm.
Is there anything I can do?
Interesting you say that,
I have about 5 or 6 Installations with Solaredge and Victron.
There is another thread on this which leans towards a problem with the SolarEdge firmware and reverting it back to a known older version can solve it.
I myself have tried some experiments and if I make sure that there is nothing connected to RS485-1 such as a meter or another inverter then it resolves itself after about 24hrs.
I left one installation where the meter is configured on RS485-1 and the modbus on RS485-2 and that has the ongoing problem. The other 5 or so that i configured modbus on RS485-1 and left the meter on RS485-2 have no such communication issues.
Maybe you can try that and see if it helps after a day or so.