Industrial information management takes a leap into the future by leveraging the latest IT developments. Dean Tresidder, software manager at Rockwell Automation, explores how integrated databases and a modular approach can make a difference.
In today’s information age, there is a huge emphasis on channelling and leveraging industrial information to streamline operations and maximise productivity. Despite the cliché, information assuredly is power. As a result, significant research has gone into the development of a new generation of industrial information systems that facilitate the extraction of plant-floor data and enhance the number of ways in which it can be used. From adopting elements of IT to innovative database design, the modern generation of SCADA and manufacturing execution system (MES) software are several steps ahead of their predecessors.
Nor does this new breed of data management focus solely on downstream processes. Certainly it has become essential to make strategic use of data coming out of the controller—but what about the configuration? Industry is recognising that optimising the time of its process engineers can also have vast improvements on overall productivity. This has spawned improvements in end-to-end information solutions; using the latest generation of integrated control architectures, system implementation and maintenance have also been revolutionised.
At the heart of all this is the new concept of ‘integration’. This no longer refers to information systems that ‘talk’ to each other, or pass on information. The modern concept of integration refers, rather, to information systems that share information—or, to extend the analogy, that mind-read instead of talk. In practical terms, this manifests as a shared database (which may even exist on the controller itself) accessed by different modules of software. The data is not moved out of the database, but can be accessed, for example, by any one of a best-of-breed historian, HMI, MES or manufacturing information system (MIS).
Single point of truth
This is in direct contrast with conventional systems, where data is copied from one database to another (and another), resulting in delays. In such a scenario, by the time the databases replicate, the data has usually changed. With an integrated architecture, the HMI has a direct view of the data on the controller, requiring just one shared database. It doesn’t matter where the data is read from, it remains constant across the whole enterprise—essentially, a single point of truth.
The benefits of this approach are obvious when it comes to using plant-floor data for trending and analysis; but the time-savings are also significant for system implementation and maintenance. This is due to the underlying concept of creating something once and using it many times—in this case the ‘tags’ created in the controller for each function in the plant. In the past, programmers would recreate in the HMI every tag that appeared in the controller, potentially many weeks of work. In a modern integrated architecture, the HMI automatically has direct access to every tag in the controller, without the need for duplication.
From a maintenance point of view, this streamlines modification of the system, since any source code that is changed in the controller is automatically made available throughout the system. There is no need for exporting or re-linking of data. The same philosophy of data-sharing is extended to alarming during plant operation. Not only does this reduce network traffic through eradication of polling of the controller by the HMI, but it also time-stamps alarms to the millisecond, making the order of events easy to isolate for diagnostic purposes.
Plant on a smart phone
It is undeniable, however, that the majority of information systems development is targeted at the downstream end of the process: extracting plant-floor information and channelling it to those who need to analyse and act upon it. Moreover, the modern information age is also the mobility age, leading to escalating demands from high-level decision-makers to have access to key information when travelling. The day of ‘plant on a smart phone’ is just about here.
Remote views into plant HMI and MIS are becoming possible by virtue of groundbreaking technology such as the Microsoft Silverlight web-browser plug-in, which is used by many global corporations to power rich Internet applications onto portable computers and mobile devices. Microsoft Silverlight functionality can be leveraged by HMI and MIS software to enable ‘thin-client’ applications with zero-installed software base. Put simply, this means that personnel can access critical plant information from any web browser—or smart phone—anywhere in the world.
Such thin-client applications essentially act in the same manner as a local HMI, providing a direct view into the shared database of an integrated architecture. However, as with any critical plant applications, the need to preserve appropriate security means that such thin-client platforms are typically read-only.
Centralised security
Managing security in industrial control systems can also be facilitated by implementing an integrated architecture. The draft ISA-99 standard, Security technologies for manufacturing and control systems, describes, among other things, several categories of security technologies and preliminary recommendations and guidance for using those security technologies.
IT-based Windows logins can be configured to provide permissions for different modules in the information system—whether controller programming, SCADA, HMI, MES, MIS or enterprise level applications. One single centralised security layer is linked to domain and IT accounts. It can be setup once to cover security privileges for all integrated applications for a particular user. Moreover, each user only has to login once to gain access to every software application required. This even extends to thin clients. ‘Security aware’ controllers within such integrated systems enforce users and connected computers to provide correct credentials in order to gain access. In some cases, an integrated audit trail is generated in both the hardware and software applications.
There is little doubt that the demands of industrial users for greater flexibility, visibility and ‘actionability’ when it comes to plant-floor data are driving the development of modern industrial information systems. By leveraging the latest IT technologies and streamlining the way industrial data is managed using a single integrated database, the latest integrated control architectures promise to revolutionise both upstream and downstream information management systems.