VigilantPlant Express: May 2007 - Essay
Why Yokogawa Developed CAMS for HIS - by Yasunori Kobayashi
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Alarm Systems, A guide to Design, Management and Procurement (EEMUA Publication No. 191), was written by individuals from major companies in the petroleum, gas, chemical, and power industries. It is regarded as the bible of alarm management and takes the fundamental approach of solving alarm flooding by not defining or generating unnecessary alarms.
This approach was adopted at many large-scale plants that experienced alarm flooding; however, it was soon realized that considerable time and resources were required to continuously review millions of existing alarms. Naturally, this prompted a search for solutions that were easier to introduce and could show results quickly. At the same time, the pursuit of increased plant safety and efficiency by integrating subsystem alarms and introducing advanced alarms (e.g. device diagnostics and predictive alarms) added to the work scope and increased the number of alarms that operators had to handle. More than ever there was a need to find a way to effectively deliver only essential alarms to only the operators that need them. Knowing all the trouble that plant operators were experiencing, Yokogawa sought a solution. What the operators wanted was for the right alarm to be sent to the right person at the right time. If this could be achieved, operators would not have to waste time dealing with unnecessary alarms. The concept seemed simple, but why could nobody came up with a solution? The answer was simple. None of the alarm systems could select or exclude alarms in real time. With its CENTUM CS 3000, Yokogawa was the first to embed a realtime alarm management system in a production control system (DCS). This real-time alarm management system is the CAMS for HIS software package. CAMS for HIS simplifies the task of adding attribute identifiers and other value-added information to existing alarm messages. Examples of such information include (1) purpose of monitoring (safety, environment, economy, etc.); (2) monitoring by individual operation mode (monitoring off during start-up, etc.); (3) response time (within 15 minutes, 1 hour, etc.); (4) alarm cause; (5) role-based procedure for responding to the alarm; and (6) actions previously taken. In addition, there is an alarm filter function, a sorting funciton that shuffles the alarm order, an eclipsing function that shows duplicate alarms on a single line, a shelving function that temporarily hides low priority alarms, and a load shedding function that displays only a limited number of alarms when alarm flooding occurs. All these functions help operators select essential alarms and exclude unnecessary alarms on a real-time basis. CAMS for HIS also has alarm rationalization functions based on the EEMUA guidelines that allow users to take the more fundamental top-down approach of identifying the root cause of problems and defining good alarms. In these ways, CAMS for HIS provides both practical and fundamental solutions for the elimination of alarm flooding. |
 Download Bulletin - CAMS for HIS* EEMUA: The Engineering Equipment and Materials Users Association |
