Emerson Picks exida for SIS Certification
exida's growing involvement in evaluation and certification services, providing a credible alternative to the German and Austrian TÜVs, has been highlighted by two recent projects for Emerson Process Management, the one involving the third-party evaluation of the Rosemount 5300 Guided Wave Radar (GWR) level transmitters for SIL 2 safety instrumented systems, and the other, certification to SIL 3 of the Ovation Safety Instrumented System (SIS).
The Rosemount 5300 series is a 2-wire GWR suitable for level and interface measurements on liquids, slurries and solids. As a result of the exida evaluation, it now has the Failure Modes, Effects and Diagnostic Analysis (FMEDA) report required to enable users in the oil & gas, refining, petrochemical, chemical and power industries to apply GWR technology while complying with the IEC 61508 and 61511 safety standards.
Five-yearly Proof Tests
The report includes a Safe Failure Fraction (SFF) of over 90% for the device, demonstrating its suitability for SIL 2 applications and provides safety instrumentation engineers with the required failure data and proof-test recommendations. The latter allow a five-year-plus proof-test interval, enabling the proof test to be coordinated with plant turnarounds, thereby minimizing process interruption and reducing the risk to personnel when conducting proof tests on live plant.
Ovation SIS is Emerson Process Management's Smart SIS offering for the power and water industries and complements its Ovation BPCS (Basic Process Control System), which is specifically designed for that sector. Its design and engineering processes have been certified by exida as suitable for SIS applications up to and including SIL 3. "Along with other industries identified as critical infrastructure sectors, there is growing demand within the power industry to follow the IEC safety standards and utilize certified equipment, especially for applications such as burner management and unit protection," explained exida director of engineering Iwan van Beurden. "Ovation SIS employs digital intelligence and diagnostics to take a complete safety instrumented function approach which increases process availability, reduces life-cycle costs and eases regulatory compliance."
Emerson's selection of exida to certify the SIS was explained by Power & Water Solutions division director of product marketing and business development Gary Woodward. "We wanted an open IEC 61508 certification using the Safety Case methodology because it provides our customers clear visibility into the certification process, giving them confidence in our design processes and products," he said. "We chose exida because it is the market leader in open IEC 61508 certification of products, especially products for process automation."