Modbus and slave connections

I’ve got a TCP Modbus sensor configured which goes to my ventilation system.
The integration works fine at start up of HA. After a while it starts throwing warnings “Updating modbus sensor took longer than the scheduled update interval”.
I deducted to issue to the fact that when I connected to my ventilation system from my laptop using qModMaster the issue arose. Makes kind of sense that you can only have one connection at a time. BUT, when I disconnect from the ventilation system from the laptop and shut down qModMaster the warning in HA remains multiple times after that fact. Actually it never seems to stop. (Only stops and works fine when I reboot HA docker container)

Where’s the culprit? In HA’s implementation or the ventilation units implementation?

Hope someone can shed some light on the subject.
Thanks in advance

I have the same type of problem in my system. I have several modbus hubs in use and I get the same “Updating modbus sensor took longer than the scheduled update interval” messages for each and every hub. I am not sure what the cause of the problem is, and have not been able to determine if it is from a specific subset of sensors either. Sorry I can’t be of more assistance, but I think it is nothing to do with your ventilation system and more to do with either pymodbus or Home Assistant.

Thanks for the reply!
After having giving it some thought it might be the HA implementation that’s faulty… Don’t know if it’s the case but I’m thinking they create a connection without closing it. And if the implementation thinks it has a connection, and that connection has been broken by another party that connects to the same slave, the implementation assumes a connection that’s not there and breaks (times out because it’s waiting for something that is not there).
Just a thought if a dev wants to give it a go…