Simatic Binding S7-300 and OPNsense Firewall

I am running the simatic binding and connected to a S7-300.
It’s working so far.

Now I subnetted my network and installed a OPNsense.
Since OpenHAB Server and PLC are in a different Network I cannot establish connection anymore.

I tried to open FW from OpenHAB to PLC any protocol and any port, but still no success.

Has anybody any clue, which ports and protocols are used?