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Quartzdyne downhole transducers offer accuracy of ±0.015% FS to 0.02% FS depending on the model. (The accuracy of the standard used in our calibrations, 0.01% of reading, must be added to these figures.) Quartzdyne's accuracy specification includes all sources of error, including the effects of repeatability, linearity, and hysteresis. This is contrary to most transducer manufacturers' practices, but we feel it is a better measure of performance. For example, a separate specifications for linearity and temperature sensitivity are meaningless, because the transducer is designed to be used with a digital correction for linearity and temperature sensitivity.
Each unit is supplied with the unique coefficients which allow pressure and temperature to be computed from the output signals. This figure shows the residual error (deviation from the polynomial fit) of a typical Quartzdyne downhole transducer. The test data used to compute the coefficients are supplied with each transducer.
Resolution of better than 0.01 psi with a one-second gatetime is typical. Counting frequency for infinite time will not provide infinite resolution: at some point, noise may limit useable information. Available resolution of Quartzdyne transducers can be 0.001 psi. We recommend gatetimes of 0.1 seconds or more.
The Series DS transducers offer 0.01% FS accuracy, over the laboratory temperature range of 0 to 40 °C, and 0.02% FS accuracy, over the field (outdoor) range from -40 °C to +85 °C.