Memory gauge and method for processing recorded raw data acquired with a memory gauge in a well. The method includes selecting a first calibration table (C.sub.1), of the memory gauge, that has a highest calibration value for the measured parameter; performing a first analysis of the recorded raw data using the first calibration table (C.sub.1) to determine a highest measured value of the measured parameter; comparing the highest measured value of the measured parameter with highest calibration values of the plural calibration tables of the memory gauge; and when a highest calibration value of a second calibration table is closer to the highest measured value of the measured parameter than the highest calibration value of the first calibration table, selecting the second calibration table (C.sub.2); and performing a second analysis of the recorded raw data using the second calibration table (C.sub.2) to generate measured values of the measured parameter.

Methods and systems for diagnosing a sensor can involve detecting a group of sensor signals output from a sensor, and differentiating from among the sensor signals to distinguish inequalities in the sensor signals for an indication of a potential fault in the sensor. A small sensor signal can be identified from a larger sensor signal among the sensor signals for the indication of the potential fault in the sensor. The sensor can include a group of piezo-resistive Wheatstone bridge elements, and in some embodiments, the sensor may be a pressure transmitter.

A fluid sealing device and a pressure detector calibration device are provided to enable further reducing of errors between a sealing pressure and a set pressure in a fluid flow path. The fluid sealing device includes a pressure sealing structure having a fluid inlet, a fluid outlet, and a fluid flow path formed therein, a temperature controller, a temperature detector, a pressure detector, an inlet-side on-off valve, an outlet-side on-off valve, a restriction part, a fluid supply device, a fluid sealing controller for sealing the fluid in the pressure sealing structure by controlling the fluid supply device, the inlet-side on-off valve, and the outlet-side on-off valve, wherein the fluid sealing controller opens the outlet-side on-off valve after increasing the pressure in the fluid sealing structure to a primary pressure higher than the set pressure, and closes the outlet-side on-off valve when a value detected from the pressure detector becomes a corrected set pressure by an error correction value corresponding to a temperature detected by the temperature detector at the set pressure.

A fluid sealing device and a pressure detector calibration device are provided to enable further reducing of errors between a sealing pressure and a set pressure in a fluid flow path. The fluid sealing device includes a pressure sealing structure having a fluid inlet, a fluid outlet, and a fluid flow path formed therein, a temperature controller, a temperature detector, a pressure detector, an inlet-side on-off valve, an outlet-side on-off valve, a restriction part, a fluid supply device, a fluid sealing controller for sealing the fluid in the pressure sealing structure by controlling the fluid supply device, the inlet-side on-off valve, and the outlet-side on-off valve, wherein the fluid sealing controller opens the outlet-side on-off valve after increasing the pressure in the fluid sealing structure to a primary pressure higher than the set pressure, and closes the outlet-side on-off valve when a value detected from the pressure detector becomes a corrected set pressure by an error correction value corresponding to a temperature detected by the temperature detector at the set pressure.

A pressure transducer is disclosed that includes an absolute pressure sensor assembly, a differential pressure sensor assembly, a main pressure port in communication with the absolute pressure sensor assembly and the differential pressure sensor assembly, a reference pressure port in communication with the differential pressure sensor assembly, and a compensation circuit in communication with the absolute pressure sensor assembly and the differential pressure sensor assembly. The compensation circuit is configured to reduce an error in an output of the differential pressure sensor assembly (due to absolute pressure) by at least a portion of an output received from the absolute pressure sensor assembly.

The invention relates to relates to a pressure cell configured for working according to the piezo-resistive principle and for use under high-energy radiation, particularly for use in space, i.e. to work under cosmic radiation. In order to reduce radiation drift effects during operation of the pressure cell, the pressure cell is treated with a radiation hardening procedure comprising an exposing of the cell with a radiation dose up to a saturation range of a radiation drift curve or above.

A positive airway pressure device is disclosed herein. The positive airway pressure device includes a blower, a buffer chamber, a gas manifold, a first sensor, a second sensor, and a controller. The buffer chamber is downstream of the blower. The buffer chamber configured to receive gas generated by the blower and output the gas to a patient. The gas manifold is fluidly coupling the blower to the buffer chamber. The first sensor is at least partially disposed in the gas manifold. The first sensor is configured to measure a first pressure in the gas manifold. The second sensor is at least partially disposed in the buffer chamber. The second sensor is configured to measure a second sensor in the buffer chamber.

The invention relates to a method for monitoring the function of a capacitive pressure measuring cell (10) comprising a measuring capacitor (C.sub.M) and a reference capacitor (C.sub.R) as well as a temperature element, wherein in an evaluation unit the pressure measurement value p is obtained by forming the quotient Q from the capacitance values of the reference capacitor (C.sub.R) and the measuring capacitor (C.sub.M). The method is characterized by the following method steps: in a matching procedure the characteristic curve of the quotient Q and the capacitance values of the measuring capacitor (C.sub.M) are each stored in a lookup table versus the pressure and at different temperature scenarios; then the corresponding absolute value of the quotient Q and of the capacitance value of the measuring capacitor (C.sub.M) from the lookup table are continuously assigned respectively to the determined pressure measurement value p at the temperature detected at this moment by the temperature element; the behavior of the course of the two absolute values of the quotient Q as well as of the capacitance value of the measuring capacitor (C.sub.M) is compared with each other; in the case of a significant deviation from an expected behavior, the evaluation unit is temporarily switched into a safety mode and meanwhile the gradient of the temperature element is detected and evaluated; in the case of a significant increase of the gradient of the temperature element, a temperature compensation is initiated; or in the case of an unchanged gradient of the temperature element, an error signal is generated.

A device and a method evaluate signals from one or more Wheatstone bridges. The requirements of ISO 26262 are taken into account by mixing a test signal with the measurement signal before amplification and before analog-to-digital conversion. After amplification and analog-to-digital conversion, the measurement signal and the test signal are unmixed again. If the test signal does not meet the expectation, the amplifier and/or the analog-to-digital converter is determined to be faulty.

A device and a method evaluate signals from one or more Wheatstone bridges. The requirements of ISO 26262 are taken into account by mixing a test signal with the measurement signal before amplification and before analog-to-digital conversion. After amplification and analog-to-digital conversion, the measurement signal and the test signal are unmixed again. If the test signal does not meet the expectation, the amplifier and/or the analog-to-digital converter is determined to be faulty.