Hello everybody.
Which cable is used for connection between 2 Interface modules ?
Do I understand correctly that it depends on the kind of field bus ?
That means if I have Profibus DP these will be RS-485 cables and for instance if I have Profinet (Ethernet, EtherCAT) these will be RJ-45 8P8C cable ?

Hello Yurets!

Yes, that is correct. Different fieldbus technologies will used different cables. Profibus, for example, is a serial based communication protocol that uses a DB9 connector, where as Profinet and EtherCAT are Ethernet based technologies. Even when generic cables may be used between devices, it is always best to use official Profinet/Profibus cables etc. to ensure quality data transfer in a noisy environment.