HESG446624R1 ABB

In recent years,PLC manufacturers provide the basis of physical layer RS232/422/485 interface on the original CPU template,gradually increase various communication interfaces,and provide a complete communication network.Due to the rapid development of data communication technology recently,users have strong requirements for openness,and the fieldbus technology and Ethernet technology are also developing simultaneously,so the PCS system composed of PLC is slightly better than the openness of DCS.At present,Rockwell AB Company has formed a multi-layer structure system,namely fieldbuses such as EtherNet,ControlNet,DeviceNet and Asi(the original DH+network is also compatible).In addition to the Profibus-DP communication network and the Profibus-FMS network,Siemens proposed the S7Routing network,namely the two-layer structure of Profibus-DP and IndustrialEnternet.The network is still developing,and our country should be actively involved in it.

近年来，PLC厂家在原来CPU模板上提供物理层RS232/422/485接口的基础，逐渐增加了各种通讯接口，而且提供完整的通讯网络。由于近来数据通讯技术发展很快，用户对开放性要求很强烈，现场总线技术及以太网技术也同步发展，所以PLC构成的PCS系统比DCS的开放性所处的现状稍好一些。目前罗克韦尔AB公司已形成了多层结构体系，即EtherNet、ControlNet、DeviceNet及Asi等现场总线(原DH+网也可兼容)。西门子公司在Profibus-DP通讯网络及Profibus-FMS网络以外，提出了S7Routing网络，即Profibus-DP和IndustrialEnternet两层结构。网络还在发展，我国应已积极的姿态投入其中。