Emerson's Micro Motion® SIS Coriolis Flow Meters Are World's First Safety-Certified To IEC 61508 Standards
Plant designers can now take advantage of the established reliability and intelligence embedded in these certified Micro Motion products to simplify new SIS designs and compliance management. Micro Motion SIS Coriolis meters integrate into the comprehensive Emerson solution for SIS that includes the DeltaV™ SIS system with smart logic solvers, final elements such as Fisher® FIELDVUE® SIS digital valve controllers, and Rosemount® SIS pressure and temperature transmitters.
This TÜV approval results from factory and device audits, as well as validation of Failure Modes, Effects and Diagnostic Analysis (FMEDA) by industry safety authority Exida. Micro Motion SIS flow and density measurement devices offer the best FMEDA scores of any Coriolis vendor. Micro Motion now has single meters approved for use with a SIL 2 capability, and dual Micro Motion Coriolis units can be used in SIL 3 functions, according to IEC 61508. No other flow meter manufacturer can match this capability.
Many process plants already rely on Micro Motion Coriolis meters from Emerson for reliable and consistent performance in process control. The extensive experience of end-users with Micro Motion Coriolis flow meters bears testimony to their quality and reliability in demanding flow and density measurement applications. This is important because, when designing SIS functions, it should be remembered that choosing the right meter for measuring the process appropriately and accurately is the first pre-requisite. Only Micro Motion SIS Coriolis meters offer the combined benefits of proven process measurement and safety-certification to IEC61508.
The data in the FMEDA report demonstrates that Micro Motion SIS meters have the best Safe Failure Fraction figures, and the lowest Dangerous Failure Rates, of any Coriolis flow meters. In other words, Micro Motion SIS meters detect far more device failures than any other Coriolis meter, and therefore are far more likely to provide high availability while providing SIS functions.
Users will find Micro Motion SIS Coriolis meters particularly advantageous in SIS applications that require a high turndown ratio of flow measurement or very accurate density measurement. These include low fuel flow (gas or liquid) to a boiler or burner; detecting composition changes via on-line density, such as the critical feed of reactor catalyst flows into an exothermic reaction; hazardous waste processing and incineration; and numerous other critical process control applications. Micro Motion SIS Coriolis can also assist customers in managing their process by anticipating disruptions caused by process conditions such as transient flow or entrained air with its unique Coriolis mass flow and density/concentration measurement capabilities. Yet another benefit is that if tight shut-off verification of an ESD valve is required in the same loop, then the meter's low-flow capability can also monitor how well the ESD valve itself is performing during the proof test.
When considering the total lifecycle cost of a sensor and transmitter, ensuring the sensor is functioning correctly can be the greatest expense. Maintenance of impulse lines in a traditional DP flow device is an example of this type of cost. The Micro Motion SIS Coriolis flow meter eliminates this expense because the sensor is the process connection, so its industry-leading diagnostics eliminate much of the time-consuming proof testing associated with other flow measurement technologies.
Micro Motion SIS flow and density meters are components of Emerson's smart SIS, an integrated solution that extends the innovations of the proven PlantWeb® digital plant architecture to enable customers to implement safer process plants and facilities. The smart SIS uses digital intelligence to automate testing throughout the safety loop — in safety-certified SIS sensors, transmitters, logic solvers and final elements — to ensure the loops perform on demand. The resulting high reliability of safety systems reduces the risk of plant trips, which keeps customers up and running.
SOURCE: Emerson Process Management