초록 ▼

A method for calibrating and linearizing the output of an instrument that includes a transducer having an output that is a nonlinear function of a property of interest of a fluid. The results of measurements performed on a plurality of transducers of the type to be used in the instrument are used to

A method for calibrating and linearizing the output of an instrument that includes a transducer having an output that is a nonlinear function of a property of interest of a fluid. The results of measurements performed on a plurality of transducers of the type to be used in the instrument are used to produce first and second equations which give the direct and inverse responses of a typical transducer. The results of further measurements on the particular transducer to be used in the instrument are used with the first equation to define how the second equation may be used to give accurate results with the particular transducer. The instrument is then calibrated and the results used with the second equation to produce an accurate linearized value for display as the output of the instrument.

대표청구항 ▼

A method of calibrating and linearizing the output of an instrument that includes a particular transducer having an output that is a non-linear function of the concentration of a gas of interest, comprising: (a) producing a first polynomial equation which is characteristic of the output of a typical

A method of calibrating and linearizing the output of an instrument that includes a particular transducer having an output that is a non-linear function of the concentration of a gas of interest, comprising: (a) producing a first polynomial equation which is characteristic of the output of a typical transducer of the type to be used in the measurement as a function of the concentration of the gas of interest, (b) producing a second polynomial equation which gives the concentation of the gas of interest as a function of the output of said typical transducer, (c) applying a gas having substantially none of the gas of interest to the particular transducer to be used in the instrument, measuring the resulting output thereof, and storing that output for use as a zero correction value, (d) applying a first gas having a first known nonzero concentration of the gas of interest to the particular transducer and measuring the actual output thereof, (e) substituting a value corresponding to said first concentration into said first equation and evaluating the first equation to determine the estimated output of the typical transducer, (f) subtracting the zero correction value from the actual output of the particular transducer to produce a zerocorrected actual output, (g) using said estimated output and the zerocorrected actual output to determine the relative sensitivity of the actual transducer, (h) applying a second gas having a second known non-zero concentration of the gas of interest to the particular transducer and measuring the actual output thereof, (i) correcting the measured output of step (h) for the zero correction value and said relative sensitivity, and using the result and the second equation to produce the linearized concentration value corresponding to said second concentration, (j) applying a sample gas having an unknown concentration of the gas of interest to the particular transducer and measuring the actual output thereof, (k) correcting the measured output of step (j) for the zero correction value and said relative sensitivity, and using the result and the second equation to produce the linearized concentration value corresponding to said unknown concentration, and (l) producing an output signal that is indicative of the ratio of said linearized concentration values and said second concentration.