0100-76124 以太网通讯大多都可采用OPC进行通讯

现场级以上的控制系统采用工业以太网，每一级的工业以太网都可以是采用不同的结构如：环形结构，树形结构等。所有以太网接口的设备都可以通过交换饥、集线器和路由器等连接到以太网网络之中。为了保证网络畅通和系统的稳定性和可靠性，建议所有的控制系统采用环形网络或者做冗余系统。

2.自动化系统的以太网网络通讯

2.1plc与PLC之间的以太网通讯

这里以西门子S7-3001400系列的PLC为例。PLC之间可采用S7通讯、S5—兼容通讯(包括ISO协议、TCP议、ISO—on-TCP协议等)，下面介绍几种常用的通讯方法。

所需硬件：2套S7-300系统(包括电源模块PS307、S7-300PLC、以太网通讯模块CP343—1)、PC机、以太网通讯网卡CP1613以及连接电缆。所需软件：STEP7。

①S7通讯

使用STEP7软件进行硬件组态和网络组态(建立S7连接)以及编写通讯程序。如果选择双边通讯要在PLC双方都编写通讯程序。S7-300PLC调用函数FB12、FB13进行通讯。S7-400调用函数SFB12、SFB13来进行通讯；如果选择单边通讯只在主动方编写通讯程序，S7-300PLC调用FB14、FB15进行通讯。S7-400调用函数SFB14、SFB15来进行通讯。

②TCP通讯

使用STEP7软件进行硬件组态和网络组态(建立TCP连接)以及编写通讯程序。PLC双方都编写通讯程序。S7-300PLC调用函数FC5、FC6进行通讯，S7-400调用函数FCSO、FC60来进行通讯。

③ISO通讯

使用STEP7软件进行硬件组态和网络组态(建立ISO连接)以及编写通讯程序。PLC双方都编写通讯程序，S7-300PLC调用函数FC5、FC6进行通讯，S7-40o调用函数FC50、FC60来进行通讯。

以上三种通讯方式的操作方法基本一致，只有在建立连接时选择各自的协议即可。

0100-76124 以太网通讯大多都可采用OPC进行通讯

The control system above the field level uses industrial Ethernet, and each level of industrial Ethernet can adopt different structures such as: ring structure, tree structure, etc. All Ethernet interface devices can be connected to the Ethernet network through switching, hubs and routers. In order to ensure the smooth network and the stability and reliability of the system, it is recommended that all the control systems adopt circular network or redundant system.

2. Ethernet network communication of automation system

2.1 Ethernet communication between PLCS and PLCS

Here Siemens S7-3001400 series PLC as an example. PLCS can use S7 communication, S5-compatible communication (including ISO protocol, TCP, ISO-ON-TCP protocol, etc.), the following describes several commonly used communication methods.

Hardware required: two S7-300 systems (including power module PS307, S7-300PLC, Ethernet communication module CP343-1), PC, Ethernet communication network card CP1613, and connection cable. Required software: STEP7.

①S7 communication

Use STEP7 software for hardware configuration and network configuration (establish S7 connection) and write communication program. If bilateral communication is selected, the communication program should be written on both sides of the PLC. S7-300PLC calls functions FB12 and FB13 to communicate. S7-400 calls functions SFB12 and SFB13 to communicate; If unilateral communication is selected, the communication program is written only in the active side, and the S7-300PLC calls FB14 and FB15 for communication. S7-400 calls functions SFB14 and SFB15 to communicate.

②TCP Communication

Use STEP7 software for hardware configuration and network configuration (establish TCP connection) and write communication program. Both sides of the PLC write communication programs. S7-300PLC calls functions FC5 and FC6 for communication, and S7-400 calls functions FCSO and FC60 for communication.

③ISO Communication

Use STEP7 software for hardware configuration and network configuration (establish ISO connection) and write communication program. PLC both sides write communication programs, S7-300PLC calls the functions FC5, FC6 to communicate, S7-40o calls the functions FC50, FC60 to communicate.

The operation methods of the above three communication methods are basically the same, only select their respective protocols when establishing a connection.