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Implementing programmable safety shutdown systems

Journal Article · · Hydrocarbon Processing; (USA)
OSTI ID:6468847
 [1]
  1. Planned Control Pty., Ltd., Boneli Beach (AU)

Traditionally, nonprogrammable hardware comprising relays, timers and signal conditioning modules have been used in safety shutdown systems. However, microprocessor technology in the form of off the shelf programmable logic controllers (PLCs) and distributed control systems (DCSs) are being used. Industry is attracted to the benefits of programmable trip systems, but is concerned about the traditional problems of: unpredictable and complex failure modes, widespread effects of failures, and spurious trips. This article discusses guidelines assembled recently by UK, German and U.S. authorities to assist industry in designing such systems. It summarizes characteristics of nonprogrammable vs. programmable trip systems in performance, operation and implementation. These generally reflect the advantage of computerized over fixed-function devices.

OSTI ID:
6468847
Journal Information:
Hydrocarbon Processing; (USA), Journal Name: Hydrocarbon Processing; (USA) Vol. 69:10; ISSN HYPRA; ISSN 0018-8190
Country of Publication:
United States
Language:
English