Open Platform Communications (OPC) and OPC UA (Unified Architecture) are standards that facilitate the exchange of data between Programmable Logic Controllers (PLCs), Human Machine Interfaces (HMIs), servers, clients and other machinery for the purpose of interconnectivity and information flow.
This kind of interconnectivity and communication is of course, essential in a manufacturing plant since there are many different kinds of equipment, devices and machinery that are measuring process parameters, producing data, or recording data.
Currently, there is an increasing emphasis on enhancing connectivity and communication in the manufacturing sector. Machinery, servers, clients and devices do not operate in isolation. Additionally, when one has different devices, software, PLCs, HMIs and machines, each producing data in their own formats, interpretation of this data is needed. This is where OPC comes in. In simple terms, OPC is a translator that can understand data from different sources and send it back and forth in the format that each source requires and understands.
Historically, classic OPC, was made up of three main separate protocols namely OPC Historical Data Access (OPC HDA), OPC Data Access (OPC DA), OPC Alarms and Events (OPC A & E) and other protocols, which were adopted by many in the manufacturing industry for their interconnectivity needs. However, classic OPC is platform dependent and relies on Windows based technologies.
OPC UA is the main successor to classic OPC and one of its main advantages is that it is platform independent so it can be easily incorporated with Windows, Linux, Mac, Android and other platforms, which is significant for the manufacturing industry where machines and systems are often running on different platforms. It also combines all the separate protocols into one specification so there is simplification. Other key advantages are that OPC UA can be deployed easily, the data exchange is secure, it can accommodate legacy systems as well as existing infrastructure and allows for scalability.
The ability to accommodate legacy systems caters to those plants and factories that do not necessarily have the budget to purchase new equipment and IT infrastructure, which is another major positive in the manufacturing context.
OPC UA has thus been adopted in the process control, oil and gas, food and beverage, waste management and pharmaceutical industries.
The role of OPC UA in the manufacturing industry
The manufacturing industry has many complex operational and communication requirements. The machines, sensors, servers, clients, applications and different devices, produce numerous outputs and data points. The data often needs to be exchanged between the machinery and devices and ultimately analyzed to improve production rates, reduce waste, increase profits and identify new value chains and business models.
Additionally, in many cases there is often a geographical context that needs to be considered. For example, consider a scenario in which a food and beverage company produces meat, cheese and other dairy products at different plants. Each of these plants have their own systems, equipment, and product lines. The company has decided that they need to focus on waste reduction and increased production rates, while remaining compliant with safety standards.
In order to meet these goals, the individual plants have to send a large amount of data to remote servers and these servers would need to be able to understand the different data from the multiple sources that they are receiving. Additionally, the company has developed a reporting application running on Linux, to generate trends based on the data from the plants. Another application was developed that runs on Windows and analyzes the trends identified by the reporting application. This application then suggests new settings for the machinery based on the trends, in order to meet the company’s goals of waste reduction and increased production rates. The main challenges in this scenario would of course be data exchange, interpretation and delivery.
An OPC UA solution would be the ideal answer to this dilemma. The company could set up OPC UA servers and these servers would be able to receive the data from all the different machines and devices at the different locations and translate the data into a format that the reporting application could use.
Moreover, the servers would also be able to communicate between the reporting application running on Linux and the application running on Windows. Lastly, the OPC UA servers could send the final, adjusted, suggested settings for the machinery, back to the plants and the machines at the plants, in the specific formats required.
The company would then be able to meet its goals in a cost-effective, efficient manner.
The main role of OPC UA in the manufacturing industry, as illustrated in the above scenario, is really about facilitating communication and breaking down the traditional barriers in industrial communication.
The main reasons why OPC UA will continue to grow in use in the manufacturing industry
The main reasons OPC UA will continue to be adopted and utilized in the manufacturing industry are:
- It enables smart manufacturing
- It contributes to the reduction of complexity in communication between devices and machinery and thus improves the overall efficiency of plants
- It can accommodate legacy systems, new machinery and product lines
- It is cross-platform
- It is not a proprietary format
- It can receive and interpret multiple data points from different sources
It is clear that OPC UA is here to stay and the standard is regularly updated to include other technologies and new standards such as mobile technology and JSON.
The manufacturing sector is a highly competitive space and companies operating in this space have to produce high-quality products on a consistent basis, in order to maintain a competitive edge. Therefore, many companies in this space are investing in various novel, innovative technologies in order to stay ahead.
OPC UA presents the answer to many of the key challenges the manufacturing sector is facing and ultimately implementation of the OPC UA standard results in less waste, higher profits, and reduced operational expenses.
Consequently, it is well positioned and able to meet the demands of the ever-changing manufacturing sector.
