What Is OLE for Process Control?

OPC (OLE for Process Control), an OLE for process control, is an industry standard. The international organization that manages this standard is the OPC Foundation, which has more than 220 existing members. Companies all over the world, including all major automation control systems, instrumentation and process control systems in the world. Based on Microsoft's OLE (now Active X), COM (Component Object Model) and DCOM (Distributed Component Object Model) technologies. OPC includes a standard set of interfaces, properties, and methods for process control and manufacturing automation systems.

opc

(Industry standard OLE for Process Control)

OPC stands for Object Linking and Embedding (OLE) for Process Control, and its appearance has established a bridge for Windows-based applications and field process control applications. In the past, in order to access data information of field devices, every application software developer needed to write a special interface function. Due to the variety of field devices and the continuous upgrade of products, users and software developers often bring a huge workload. Usually this does not meet the actual needs of the work. System integrators and developers urgently need a plug-and-play system with high efficiency, reliability, openness and interoperability

1. Industrial control solution users

2. Building control solution users

3. Industrial control solution vendors

4. Building control solution vendors

5. Industrial control solution integrator

6. Building control solution integrator

7.All areas of automation

OPC is to connect the data source (OPC server) and the user of the data (OPC application)

Prior to OPC, there was no uniform standard for the interface between hardware drivers and the applications connected to them. For example, in the field of FA (Factory Automation)-factory automation, connecting control equipment such as PLC (Programmable Logic Controller) and SCADA / HMI software requires different FA network system configurations. According to the results of a survey, among the costs required for the development of control system software, 70% of the costs are for application design of various machines, and 30% of the development of connection interfaces between machines and equipment. In addition, in the field of PA (Process Automation)-process automation, when you want to transfer all process data in a distributed control system (DCS-Distributed Control System) to a production management system, you must follow each model of each supplier. Develop a specific interface, for example, use a C language DLL (Dynamic Link Database) to connect to a DDE (Dynamic Data Exchange) server or use FTP (File Transfer Protocol) to design applications. For example, when a system consisting of 4 types of control equipment and 3 applications connected to monitoring, trending, and reporting, must spend a lot of time to develop monitoring, trending, and tables corresponding to equipment A, B, C, and D. A total of 12 drivers are required for the interface software of the application program. At the same time, the coexistence of various drivers in the system makes it more difficult to maintain the stability and reliability of the operating environment.

OPC is proposed for the purpose of standardizing the software interface between the equipment and applications of different vendors and simplifying the data exchange between them. As a result, it is possible to provide users with a process control software component product that can be freely combined without depending on a specific development language and development environment.

The system using OPC is composed of an OPC server that provides data collection services in accordance with the requirements of the application program (client program), an OPC interface necessary to use the OPC server, and an OPC application program that receives the service. The OPC server is developed according to the hardware of each supplier, so that it can absorb the differences between the hardware and systems of each supplier, so as to achieve a system configuration that does not depend on the hardware. At the same time, a data type called Variant is used to provide the data format according to the requirements of the application program without depending on the inherent data type in the hardware.

Using OPC to standardize the interface can use monitoring, trending, and reporting applications independently of the internal structure of each device and its suppliers.

Why develop OPC Server and OPC Gateway?

1.High prices of original foreign manufacturers

2. The inflexibility of the original foreign manufacturers in the face of the project

3. Diversity of subsystems in domestic projects is difficult to provide DRIVER

4. The pursuit of independent OPC server is stability, real-time and rapid.

5. Irregularity of many subsystems

6.Inconsistencies before and after bidding for turnkey projects

7, expensive original platform server software

8.Whether the general contractor integration has invested a lot of manpower development

Platform and subsystem compatibility

10. Interoperability of OPC platform and subsystems established

11.Solve the troubles of manufacturers and integrators in project integration