I/O Modules - Modbus TCP - Problem with simultaneous communication

Issue

Modules with ETH port do not communicate with more than one device simultaneously.

Possible solutions

1. Check if the network is properly configured, for example, IP addresses are not doubled, connections are not missing, etc.

2. Check if there are not more than 4 connections open on the ETH port. Four is a maximum number of connections for the module. The number of connections can be checked in the web server or in the iSMA Configurator:

   

3. Check if timeouts are not too short.

4. Check if the polling time is not too quick. Verify if with higher timeout and longer polling delay, the situation recurs.