Data historians are repositories of vital information, but how do you manage that data to ensure its integrity?Automation Worldwent in search of practical advice on how process industry users are managing historian data today.
Automation vendor ABB answered the call and reported on an informal survey of its customers. ABB has provided tens of thousands of copies of its Information Manager historian software product to process customers worldwide, and it recently unveiled the product’s successor, cpmPlus History, which is also branded as 800xA History when it is sold as a component of ABB’s System 800xA distributed control system (DCS). System 800xA users also employ third-party (non-ABB) historians.
ABB’s Marc Leroux, in charge of global marketing for ABB’s Collaborative Production Management business, and Jim Kline, product line manager for the ABB’s collaborative production management technology, provided the following answers to our questions.
For more on historian best practices, see “Distilling the Truth,” which first appeared in Automation World’s August 2012 print edition.
AW: How do users know if they data they have is accurate?
Leroux: When I polled some customers recently, they said that they know that the historian data is not valid when either someone complains, or an application fails because the values are outside of its limits. There is no easy way to verify the integrity of the data. In a general sense, most customers continue to create new key performance indicators (KPIs), and then these need to be implemented into some type of delivery mechanism (dashboards, etc.).
When I asked the follow-up question, “What percentage of data do you believe is out of sync between the control system and the historian, the answers ranged from “probably 30 percent” to one customer who just laughed and said that they haven’t been in sync since the systems were implemented.
AW: What sort of ongoing "maintenance" or monitoring of data or deliverables (HMIs, Web-based dashboards, etc.) is required to keep historian data useful? Is anyone assigned to be responsible for it?
Leroux: This is a question that I asked a few customers who I knew were using a third-party (non-ABB) historian. The general consensus was that to effectively manage a historian strategy, they would need one person to cover two to three sites, on a full time basis. The work was mainly around ensuring that new tags set up in the DCS were configured in the historian, investigating inaccuracies in the data or providing explanations for reports, and also configuring new displays.
One of the strengths that cpmPlus History (and our predecessor Information Manager) has is that any change made in the DCS (setpoints, limits, ranges, etc.) are automatically reflected in the historian, eliminating the need for this type of maintenance.
AW: Overall, what advice do you have for a company who's invested in a historian product but may be struggling to use it fully?
Leroux: Stop what you are doing. Back up and revisit the objectives you had when purchasing/implementing the historian. Then take one problem and figure out how you are going to address it. When you have one success, the rest becomes much easier. We often see customers who are trying to understand what the problem is by using the tool, rather than starting with the problem and using the tool to solve it.
AW: Are you seeing new applications that historians are being asked to support?
Leroux: We are seeing new use cases that involve unstructured networks of disconnected data, such as data collected on ships that may not be synced for several days or weeks, or data from exponentially large sources such as electrical Smart Grids, or geographically diverse areas such as wellheads in oil fields. Also, a number of our customers are exploring decentralized monitoring and control, where a virtual control room may be in India for an oil platform in the North Sea. The bottom line is that conditions change rapidly, and the use of the historian is going to have to be able to react to these changes.
