An Introduction to Plant Monitoring through the EPICS Control System

John A. Carwardine
Argonne National Laboratory

The Experimental Physics and Industrial Control System (EPICS) environment provides the framework for monitoring of any equipment connected to it. Various tools offer engineers and scientists the opportunity to easily create high-level monitoring applications without having to rely on expert programmers to develop custom programs. This paper is aimed at the first-time or casual user, providing the essential information for using several of the tools. Examples are taken from applications in daily use at APS. The reader is introduced to the concept of Process Variables which provide the link from control system tools to the actual hardware. The EPICS 'alarm handler' tool alerts the operator to events such as a power supply trip or a bad vacuum reading. This tool is described and the user is guided through the steps needed to configure it for a particular application. The plant monitoring capabilities provided through EPICS are exploited by several programs in the Self-Describing Data Sets (SDDS) toolkit. The SDDS concept is described using a simple text file as an example. The reader is then introduced to the program 'sddsmonitor' for collecting data from several Process Variables at once, and to 'sddsplot' for graphically displaying the data collected.