Their goal was to detect abnormal situations in the process and protect field devices from malfunctions. HART Communication enables online data from field devices and the Distributed Control System (DCS) to connect without disturbing the installed 4-20mA analog signal and wiring.
That connection is critical to the plant’s success because diagnostic parameters that help detect signs of an abnormal situation or degrading performance are difficult to obtain with simple handheld device which require a time-consuming, manual, step-by-step approach.
Instead, HART-compliant devices are integrated and visible directly from the DCS and asset management applications in the control room, requiring no manual intervention.
HART technology made it possible to quickly access this data without manual operation. This made it much easier for them to gather data and opened up many possibilities to detect abnormal situations in field devices. Valves, pressure transmitters, and analyzers are high-maintenance devices and they look forward to additional applications with vortex flowmeters, Coriolis flowmeters, and valve positioners. They estimate that cost savings is more than 10% due to the use of HART features in the devices.
So far, the Mitsubishi plant has connected approximately 800 HART technology-enabled devices directly to the control room. Because HART Communication is interoperable, Mitsubishi was able to rapidly gain remote access to the information in their instrumentation. Differential pressure transmitter data in particular played a key role in the benefits achieved.
Advanced HART diagnostics from the pressure transmitter allowed them to quickly detect the onset of a plugged impulse line in a naphtha flow application as well as a plugged manifold during start-up. It also allowed the team to measure flow-loop variability, which helped identify an area of unstable flow due to inadequate pipe length. Furthermore, HART technology reduced the time and effort of root-cause analysis and a more rapid discovery of the problem.
HART Technology has become a standard communication protocol for the plant. Plans call for gradual upgrades to the plant’s remaining 2,200 analog-only devices with HART technology. Additionally, the company is currently testing WirelessHART devices for their wireless applications.