YPC111 ABB

In the communication network of the PLC system,the communication rate of the upper-level network should be greater than 1Mbps,and the communication load should not be greater than 60%.The main forms of the communication network of the PLC system are as follows:

(1)The PC is the master station,and multiple PLCs of the same type are the slave stations.A simple PLC network is formed.

(2)One PLC is the master station,and other PLCs of the same type are slave stations,forming a master-slave PLC network.

(3)The PLC network is connected to the subnet of the DCS in the large DCS through a specific network interface.

(4)Dedicated PLC network(dedicated PLC communication network of each manufacturer.

In order to relieve the CPU communication task,according to the actual needs of the network composition,communication processors with different communication functions(such as point-to-point,field bus,industrial Ethernet)should be selected.

PLC系统的通信网络中，上级的网络通信速率应大于IMbps，通信负荷不大于60%。PLC系统的通信网络主要形式有下列几种形式：

（1）PC为主站，多台同型号PLC为从站。组成简易PLC网络。

（2）1台PLC为主站，其他同型号PLC为从站，构成主从式PLC网络。

（3）PLC网络通过特定网络接口连接到大型DCS中作为DCS的子网。

（4）专用PLC网络(各厂商的专用PLC通信网络。

为减轻CPU通信任务，根据网络组成的实际需要，应选择具有不同通信功能的（如点对点、现场总线、工业以太网）通信处理器。