UNICOS framework and EPICS: A possible integration

UNICOS (UNified Industrial Control System) is a CERN-made framework to develop industrial control applications. It follows a methodology based on ISA-88 and provides components in two layers of a control system: control and supervision. The control logic is running in the first layer, in a PLC (Programmable Logic Controller), and, in the second layer, a SCADA (Supervisory Control and Data Acquisition) system is used to interface with the operators and numerous other features (e.g. alarms, archiving, etc.). UNICOS supports SIEMENS WinCC OA as the SCADA system. In this paper, we propose to use EPICS (Experimental Physics and Industrial Control System) as the supervision component of the UNICOS framework. The use case is the control system of a CO$_{2}$ cooling plant developed at CERN following the UNICOS methodology, which had to be integrated in a control system based on EPICS. The paper describes the methods and actions taken to make this integration feasible, including automatic EPICS database generation, PLC communications, visualization widgets, faceplates and synoptics and their integration into CSS and EPICS, as well as the integration with the BEAST alarm system.