Just Like Distributed Control, Distributed Safety Is Coming Soon to a Process Plant Near You, Maybe Your Own
In the beginning, all control was distributed in the field near each particular process. Much of this control was manual, with islands of pneumatic-based automation. Then came the inaptly named “distributed control system,” which was, in fact, centralized automation in the control room and its environs via monolithic centralized controllers and accompanying I/O.
But smart instruments, local valve controllers, digital fieldbus networks and other new technologies moved control out into the field—closer to the processes and often to field-based operations personnel. This resulted in the current architecture of most process automation systems, namely, distributed control with automation and operator interfaces applied as needed in the control room and throughout the plant.
Process safety systems are following much the same path: first distributed, or often non-existent systems; then centralized via triple-modular-redundant safety controllers and local I/O; and now distributed via SIL-rated safety networks connected to safety-rated intelligent I/O, and via ever smarter and often redundant instruments and controllers.
From: ControlGlobal.com