A process control/electrical control room design standard

The design of electrical, process, and operator control rooms for specific integrated mills (i.e. bleached board, paper, or kraft mills) is described. The design is for seismic/hurricane conditions. Studies and surveys have shown the need to upgrade the environments in all control rooms containing critical equipment that are known to have unacceptable atmospheric corrosivity. The main concern is protection of control devices and microprocessor-based systems. Experience with the upgrading of an existing electrical control room (ECR) is discussed. Motor control center internal starter wiring had deteriorated to the point of breaking off at the connectors. The room was sealed and a deep-bed activated carbon filter unit installed. At this time, units were also installed for two ECRs serving paper machines. Experience with these systems led to the development of the present guidelines. Corrosivity surveys indicated considerable variation within the plant site. This also varies slightly with the season and the prevailing wind direction.<>