Issue with multiple modbus getter nodes

Hello guys,

I have an issue with the use of multiple Modbus-Flex-Getter nodes.
I am working with raspberry pi 3b+ and use following software versions:

I have expanded my project to communicate now with 3 solar inverters and 1 energy meter, on basis of modbus-tcp. As I said I use modbus-flex-getter for data collection. For every connection I have configured a separate modbus-server configuration.

My problem is as follows, now that I have increased from 3 to 4 connections, there is always 1 that is not reading data for some reason. Every time I restart node-red. There is only 3 connections reading data, the one not reading data is quit random. I also tried decreasing polling time from 1 sec to 10 sec, but that doesn't seem to be the cause. The connection that's not reading data, cycles through:
->reconnect->initialize->connected->queuing .... and back again.

My question is, is there some sort of limitation on the number of connections you can make, or is there another cause for this problem?

There will be a limit (memory/CPU/resources) but 4 connections is pretty low.

Likely something something else. Perhaps you are running parallel reads? Or the connection to the fourth device is noisy? Or something else...

@Steve-Mcl I just found the cause.

I have my running project that I only update with changes after rigid testing these changes on a test RPI.

On my test RPI I communicated 4 times with the same energy meter.
Up to three times went well, but 4 times was somehow too much.

So I implemented the energy meter on my running project and there it worked well, so with 3 inverters and now extra 1 energy meter.

So three times seems too be the max number of connection to 1 IP-address with modbus-tcp.

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