opc is neither hardware nor software. OPC is a communication specification, a set of specifications stipulated by the OPC Foundation. Write programs according to this specification, including an OPC server program and an OPC client program. As long as they are written according to the specification, no matter who wrote them, the OPC server can be guaranteed to be accessed by OPC clients.

opc server can read the data of equipment, such as PLC, DCS, etc., but this part of OPC specification does not matter. As long as the manufacturer reads the equipment data with any interface and any method, it is OK, and then the OPC server program opens these read data on the network according to the specification requirements. Other OPC client programs can browse these data remotely and choose to read what is needed in these data.

extended information

working principle of OPC

OPC takes the mechanism of OLE/COM as the communication standard of application, and OLE/COM is a client/server mode, which has the advantages of language independence, code reusability and easy integration.

The code in p>OPC server determines the naming rules of equipment and data accessed by the server, data items and details of data accessed by the server. No matter what form the field equipment exists, customers access it in a unified way, thus ensuring the transparency of the software to customers and making users completely separated from the low-level development.

the client application only needs to use the standard interface to communicate with the server, and does not need to know the underlying implementation details. Through OPC server, OPC customers can not only directly read and write the data of physical VO devices, but also operate the port variables of SCADA, DCS and other systems (as long as the system provides OPC services).