Fieldbus Communication • 91ETHERNETWAGO-I/O-SYSTEM 750ETHERNET TCP/IPThe WAGO ETHERNET TCP/IP fieldbus node does not require anyadditional master components other than a PC with a network card. So, thefieldbus node can be easily connected to local or global networks using thefieldbus connection. Other networking components such as hubs, switches orrepeaters can also be used. However, to establish the greatest amount of“determinism” a switch is recommended.The use of ETHERNET as a fieldbus allows continuous data transmissionbetween the plant floor and the office. Connection of the ETHERNET TCP/IPfieldbus node to the Internet even enables industrial processing data for alltypes of applications to be called up world-wide. This makes site independentmonitoring, visualization, remote maintenance and control of processespossible.4.1.2 Network Architecture – Principles and RegulationsA simple ETHERNET network is designed on the basis of one PC with anetwork interface card (NI), one crossover connection cable (if necessary),one ETHERNET fieldbus node and one 24 V DC power supply for thecoupler/controller voltage source.Each fieldbus node consists of a (programmable) fieldbus coupler orcontroller and a number of needed I/O modules.Sensors and actuators are connected to the digital or analog I/O modules onthe field side. These are used for process signal acquisition or signal output tothe process, respectively.Fig. 4-1. Connection Example and Principle of a Fieldbus Node for a Network Architecture1NetwerkknoteneFieldbus communication between master application and (programmable)fieldbus coupler or controller takes place using the implemented fieldbusspecific application protocol, e. g. MODBUS TCP (UDP), EtherNet/IP,BACnet, KNXNET/IP, PROFINET, Powerlink, Sercos III or others.
