Rosemount Analytical links safety with process analyzers

By Control Engineering Staff February 1, 2001

I n the past, many analytical analyzers were so temperamental that users often refused to allow them to be directly connected into the control system. Instead, control systems would interface with the analyzer through an operator who would observe the readings and ‘tweek’ the control system accordingly. In order to ensure system safety when their analyzer is part of the control system, Rosemount Analytical (Orrville, O.) has developed and obtained a control safety patent for its Raman Process Analyzer and other optical analyzers.

The Raman Process Analyzer uses the Rayleigh backscatter principle to provide reliable laser cessation for increased safety. While the probe is in the process sample, the laser remains active to measure both Raman backscatter as well as Rayleigh backscatter. When the probe is removed from the process, the amount of Rayleigh backscatter decreases drastically causing the laser within the probe to shut off immediately and automatically for operator safety. If the process vessel is empty or if the fiber-optic cables are damaged the laser automatically shuts off, reducing the potential for ignition. Unlike most laser safety mechanisms for optical analyzers, Rosemount Analytical’s design requires no hazardous wiring to be run from the analyzer to the probe thus reducing the risk of ignition and explosion. Rosemount Analytical offers the only Raman process analyzer to meet OSHA 1910 safety regulations.

According to Ramasamy Manoharan, manager of spectroscopy products technology at Rosemount Analytical, the Raman analyzer delivers value where other techniques have not been successful. Rather than measuring the absorption of light by samples, Raman spectroscopy measures the light scattered by molecules. The analyzer’s design permits analysis of processes containing bubbles, suspended particulate, and viscous polymeric materials. Furthermore, the Raman analyzer can measure organic and inorganic constituents in aqueous processes in addition to its capability for analyzing organic specialty chemicals and hydrocarbons.

Mr. Manoharan adds that the Raman Analyzer revolutionizes information management by acting not only as an analyzer, but also as a server providing instant diagnostics, calibration capabilities, alarms, and process information anywhere the internet is accessible in an easy to manipulate web page format. The system maintains information integrity through the use of password protection. Via Ethernet connections, the Raman analyzer can be established on both local or wide area networks. These capabilities are especially beneficial for analyzer maintenance and for facilities that combine business management with process information.

For more information,visit Rosemount Analytical’s website at www.processanalytic.com

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