DCS Tools for Effective Power Failure Response

Effective response to a power loss event is critical to the safety and mechanical integrity of a manufacturing plant. Power failures can lead to accidents, injuries, loss of primary containment (LOPC), government recordable events, mechanical failure and loss of production. Due to the unpredictability of a power event, there is no single solution or response plan that can mitigate all of the potential issues that a power event creates.

A power event can cause alarm showers/floods which prevent the operator from seeing and reacting to high consequence alarms that could prevent a serious incident if responded to in a timely manner. Based on this, we performed investigation into the last several power failure events at our sites with a focus on the distributed control system (DCS) and its impact on response to power events. This presentation covers the findings from this investigation which include when power events occur, alarm counts/metrics during the events, the severity of each different power event, and findings during root cause investigations (RCI).

We then discuss the different tools that have been implemented into the DCS specifically to aid in operator response to a power event. Some of the tools that are covered in this presentation are DCS graphics "overview" screens for power failure events which provide one-click capability to layer 3/4 process graphics, alarm hiding/suppression concepts, bulk alarm acknowledgement/unlatching techniques, alarm silencing, and automated actions in logic/programming to build more resiliency against an event.