The port reserved for the TSX ETY or TSX ETY PORT (TSX P57 1634/2634/3634) module or the Ethernet port of the TSX P57 6634/5634/4634 is TCP port 502. When a client wishes to access the server of these modules, it must send towards this port.

If a TCP connection cannot be established (when the destination is absent for example), the timeout error occurs after 80 seconds.

Each communication function timeout must be set to a value higher than 80 seconds if the first exchange was not successfully completed.

The TCP layer sends a "keep alive" frame almost every two hours so that breaks in connection can be detected (for example, cable disconnection, detection of power outage from the client by a server, etc.). Elsewhere in this guide is a discussion of broken connections.