The extensive digitalisation of processes within industrial production has been a key goal for some time now in practically all branches of industry. Concepts such as Industry 4.0 and the Industrial Internet of Things (IIOT) are intended to create the conditions to increase companies’ competitiveness and to equip them better for the future.
From sensors to production control systems, all the components, systems and equipment must speak a common language. The OPC Foundation, established in 1996, set itself the task of creating the foundations for this uninterrupted communication and has defined comprehensive specifications and standards over the past 20 years. For several years now the current iteration, known as the OPC Unified Architecture (OPC UA), has been the most important standard for platform-independent data exchange and is already widely used in industry.
The OPC UA Companion Specifications describes the variety of technical systems within the industry and defines the relevant special requirements that, for example, significantly differ in terms of sensors, control systems or robotics and which cannot be sufficiently covered in just one overarching standard. Recently, twelve world-leading manufactures in this sector have defined their own OPC UA Companion Specification for weighing technology, with the support of the German Mechanical Engineering Industry Association (VDMA) and the Institute for Control Engineering of Machine Tools and Manufacturing Units (IWS) of the University of Stuttgart. As one of the world’s leading industrial weighing and inspection technology manufacturers, Minebea Intec was substantially involved in the development of the OPC UA Companion Specification for Weighing Technology (VDMA-Standard 40200: 2020-06).
OPC UA-specified weighing technology
Janine Nickel, Product Manager Weighing Electronics at Minebea Intec, explains how extensive and ambitious the definition of this OPC UA Companion Specification was: “Weighing processes are an integral part of many production steps, from supply and temporary storage of raw materials to the actual production of the goods through to the packaging and delivery of the finished products. Regardless of the respective industry branch, this usually involves a range of scales and weighing systems, which can be automated or manually operated, cover a broad range of weight classes and must meet the defined accuracies.” The definition should cover all common weighing systems in the industry if possible, from simple standard industrial scales to vehicle, silo and individual scales as well as laboratory balances through to continuously weighing checkweighers.
According to Janine Nickel, additional complications arose since, so far, each weighing system manufacturer had created their own protocols and used their own data structures, meaning the definition of variables already differed from manufacturer to manufacturer. “In the past this lead to high costs and long time frames for the user when integrating weighing systems. Thankfully, this unsatisfactory situation is now a thing of the past thanks to the OPC UA Companion Specification for Weighing Technology definition.”
Definitions applying for all manufacturers
All of the details defined in the OPC UA Specification for Weighing Technology will considerably simplify the integration of weighing systems into user’s processes. Communication is based on a client-server model for OPC UA and the established standard Ethernet TCP/IP as a data interface. An essential part of the VDMA specification 40200: 2020-06 is the definition of data and types of variables as well as all objects. This is now regulated for all manufactures to ensure there are no problems or errors with the provision and processing of the measured values, even in systems with scales from different manufacturers.
“The weighing system manufacturers must now take the next step to ensure that the OPC UA Companion Specification for Weighing Technology is promptly put into practice so that users can convert their products to OPC UA-based architectures as simply as possible,” underlines Janine Nickel. Companies with existing systems are faced with the challenge that the scales they are currently using do not yet meet the new specification, as completely replacing all weighing systems is not realistic for a number of reasons. For one thing, scales with integrated OPC UA servers and Ethernet TCP/IP interface in accordance with the OPC UA Companion Specification for Weighing Technology are not even available on the market at the moment; manufacturers need to develop this new generation of products first. Not only this, but the conversion costs for manufacturers must remain reasonable and cost-effective, which makes the complete replacement of older scales due to the OPC UA-specified weighing technology unrealistic in many cases.
The software miOPC is the answer
As a pioneer of the OPC UA Companion Specification for Weighing Technology, Minebea Intec has developed an available solution to bring existing weighing equipment up to the new standard with minimum effort. The software solution, miOPC, can be installed as the OPC UA server, either on an available PC in the network or connected locally to the appropriate scale via a simple mini PC. The connection to the scale can either be via the Ethernet TCP/IP or via the existing serial RS232 interface. Existing internal protocols such as XBPI are easily implemented by the OPC UA server, so that even scales that are already installed are extremely easy to upgrade retrospectively to comply with the OPC UA Companion Specification for Weighing Technology.
miOPC offers high flexibility in relation to the possible architectures and enables configurations in which, for example, one or more scales can be directly connected to an existing internal Ethernet TCP/IP-network and networked via the OPC UA-network clients. Scales with serial RS232 interfaces can use this interface to connect to their own OPC UA server and in doing so be integrated into the company network. miOPC even makes it easy to connect to different locations via the internet in order to communicate the measurement data of different production systems regardless of where they are. In this way, miOPC ensures the scale can be integrated into the existing IT structure with no problems.
Minebea Intec has developed an intuitive user interface for the simple administration of OPC UA-specified weighing technology. It is always available via browser application, no matter where you are and no additional applications need to be installed. miOPC also uses the latest data encryption algorithms to meet even the highest data security standards between server and client. Another advantage of miOPC is that it is programmed using .NetCore and can be flexibly installed on many of the latest available operating systems.
“Some of Minebea Intec’s products are already suitable for use with miOPC, including the industrial scales Combics, the bench scales in the Signum series, the bench and floor scales Midrics, and the high-resolution weighing platforms of the Industry Supreme family,” Janine Nickel says, describing Minebea Intec’s current progress. “However, further developing the miOPC is a top priority for us and we will soon be launching releases which will cover more of Minebea Intec’s products and functions.” According to Nickel, the integration of an OPC UA sever will be an integral part of the design for new products to be released in future. Customers can convince themselves of the benefits of software miOPC risk-free through a free 30-day trail of the demo version.
“We have been heavily involved in the definition of the OPC UA Companion Specification for Weighing Technology based on the benefits it provides for users and have been quick to implement the set requirements for miOPC,” Nickel emphasises. “This software provides our customers with a simple-to-use, intelligent, reliable and cost-effective solution for integrating all of our industrial scales into modern IT architectures. This makes it easy to implement weighing systems, enabling operating system-independent data exchange between scales and overarching systems up to ERP or MES level. In this way, Minebea Intec is creating the conditions for weighing technology to effectively transition to the next phase of Industry 4.0.”