An asset management system can help plants figure out that something’s about to blow before the equipment actually blows. Asset manager software applications can read device data through a fieldbus network to interpret and display the device’s problem before the device fails and shut down the process.

One such fieldbus with device information protocols is Hart, from the Hart Communications Foundation. The power plant at The Ohio State University, in Columbus, Ohio, was using Hart to communicate with its instruments at least 10 years before the plant took the extra step and installed asset management. It previously used only the 4 to 20 milliamp (mA) communication capability available through Hart without tapping into the rich device information residing in the network protocol. “I didn’t even know what asset management was until four years ago,” says Jerry Lowery, a controls systems engineer at the University plant.

The asset manager lets plant engineers know how each individual device is working and whether it’s positioned or calibrated correctly. “When an instrument has an issue, we know immediately, especially a valve position,” says Lowery. “Now we can replace it before it breaks. In the past, we did nothing. We wouldn’t catch it until the yearly evaluation.”

Another benefit from the fieldbus network and asset manager is the ability to use devices from different manufacturers. “We use a lot of different vendors for our field devices,” says Lowery. “But as long as we’re using a vendor that uses a standard DD (device description), we don’t have a problem.”

If it ain’t broke...

Asset management systems are using fieldbus networks to monitor and manage instrument behavior. This system allows maintenance personnel to watch the instrument as it streams data to the user interface. The engineers can see how the device is working and keep a history of the device’s behavior. The system can actually match the device behavior with its history to determine whether the part is at any risk of failure. In the past, plants would typically schedule a maintenance shutdown and replace all devices whether they were about to fail or not. With asset managers, operators are shifting from preventative maintenance (replacing instruments, broken or not) to predictive maintenance (replacing devices only when they’re as risk of failure).

Smart devices have the capability to alert users of their problems even without the use of an asset management system. The asset manager, however, can take the device data a step further and present a detailed context of device data for plant operators. “Because these devices are smart, they can diagnose themselves and record this diagnostic information,” says Tim Sweet, manager of product management for Asset Management, a division of process controls vendor Honeywell Process Solutions, in Phoenix. “But that’s only half the game. With bus technology, those diagnostic status messages can be communicated back to a centralized computer system, which can synthesize the data so that it is meaningful to the maintenance and reliability engineer.”

Asset managers can help plant operators absorb the flood of device data and view it in a comprehensive format.
“Take a medium-size refinery that is producing 150,000 barrels per day. That plant is responsible for about 2,000 controls,” explains Wil Chin, analyst at ARC Advisory Group Inc., in Dedham, Mass. “You can’t manage all those loops without help.
The asset management system is able to look at all the devices and check on the one with a possible fault. It can look at that device’s history and see its trends. It can see the one transmitter that is reading different from the others.”

The asset management system is able to monitor process operations while also looking at maintenance needs and potential problems. “Asset management has two main focuses. One is the management of the assets and the other is maintenance,” says Moin Shaikh, consultant at Siemens Energy & Automation Inc., the Alpharetta, Ga.-based automation vendor. “When it’s used to manage the assets, the system offers efficiency advantages. We have customers who don’t want any unplanned downtime. So the asset manager uses the fieldbus network to monitor for anything that might cause downtime.”

One of the goals of the asset management system is to help the maintenance  department shift from preventive maintenance to predictive maintenance. That means fewer shutdowns and an end to replacing parts that are functioning well.

For maintenance engineers, the asset manager presents the device data in the context of its history, including any instances of problems ...