ISA Interchange

Free Tech Paper Week: Calibration & validation philosophy for TDL analyzers

Written by Contributing Authors | Jul 14, 2011 5:14:34 PM

In our continuing effort to grow the Interchange into the top source for technical content in the automation field, the ISA Interchange will be sharing several technical papers over the next several days. We hope you enjoy them. Our first paper was presented by Dr. Janardhan Madabushi, David Fahle, and Dr. Christian Heinlein at the ISA 55th Analysis Division Symposium 2010. Read below for the abstract, then check out the full article at the bottom of the post.

Abstract

Gas analyzers based on Tuneable Diode Laser (TDL) Absorption Spectroscopy are now
widely accepted in the industry as process analyzers because of their reliability and low
maintenance. TDL analyzers offer a non-contact, optical measurement without moving parts
with most manufacturers recommending a calibration frequency of up to one year. This
extended calibration interval has raised skepticism among industry users because it is
contrary to their experience with traditional analyzers, which require more frequent
calibration, supported by most maintenance protocols which call for frequent validation and
calibration. This paper will discuss the calibration and validation philosophy for TDL
analyzers in process applications.