An industrial process differential pressure sensing device includes a housing having first and second isolation cavities that are respectively sealed by first and second diaphragms, a differential pressure sensor, a static pressure sensor, an eddy current displacement sensor, and a controller. The static pressure sensor is configured to output a static pressure signal that is based on a pressure of fill fluid in the first isolation cavity. The differential pressure sensor is configured to output a differential pressure signal that is indicative a pressure difference between the first and second isolation cavities. The eddy current displacement sensor is configured to output a position signal that is indicative of a position of the first isolation diaphragm relative to the housing. The controller is configured to detect a loss of a seal of the isolation cavity based on the position signal, the static pressure signal and the differential pressure signal.

An industrial process differential pressure sensing device includes a housing having first and second isolation cavities that are respectively sealed by first and second diaphragms, a differential pressure sensor, a static pressure sensor, an eddy current displacement sensor, and a controller. The static pressure sensor is configured to output a static pressure signal that is based on a pressure of fill fluid in the first isolation cavity. The differential pressure sensor is configured to output a differential pressure signal that is indicative a pressure difference between the first and second isolation cavities. The eddy current displacement sensor is configured to output a position signal that is indicative of a position of the first isolation diaphragm relative to the housing. The controller is configured to detect a loss of a seal of the isolation cavity based on the position signal, the static pressure signal and the differential pressure signal.

A pressure sensor apparatus is disclosed. The pressure sensor apparatus includes a bulk acoustic wave (BAW) die having a die interface side and a pressure contact side, a sensor BAW resonator and a reference BAW resonator disposed on the die interface side of the BAW die, a control circuit die coupled to the die interface side of the BAW die via an attachment layer, and an extended opening on the pressure contact side that extends into a depth of the BAW die and is generally aligned with the sensor BAW resonator, the extended opening being configured to translate an external pressure on the pressure contact side onto the sensor BAW resonator.

A method for remotely measuring pressure of a fluid in a container includes determining a spatial location of first and second resonant radiofrequency antenna elements located on a radiofrequency identification (RFID) tag located in the container. The first antenna element is positioned in a fixed position on the RFID tag and the second antenna element is positioned on a deformable element configured to be deformed in at least one dimension based on pressure from the fluid. The spatial location is determined from a radar image generated based on reflected radiofrequency beams from a scan area and re-radiated radiofrequency beams from the first and second antenna elements located within the scan area. A pressure value is determined for the fluid based on the spatial location of the first and second antenna elements. Systems and methods of remotely measuring pressure using passive RFID tags are also disclosed.

A gas-detecting apparatus, having a gas inlet and a gas outlet, for detecting a false alarm is disclosed. The gas-detecting apparatus comprises a control module, a sensor module, and an air chamber. In an example embodiment, the sensor module is electrically connected with the control module. The sensor module has a sensor inlet and a sensor outlet. The sensor inlet is fluidly coupled to the gas inlet of the gas-detecting apparatus. The air chamber has an air inlet and an air outlet, wherein the air inlet is fluidly coupled to the gas inlet of the gas-detecting apparatus and the air outlet is fluidly coupled to the gas outlet. The control module is configured to receive a first sensing signal for a first level of gas from the sensor module and determine whether magnitude of the first sensing signal is higher than a first threshold value. In an instance when the magnitude of the first sensing signal is higher than the first threshold value, the control module causes the air chamber to supply ambient air to the sensor module through the sensor inlet of the sensor module.

A gas-detecting apparatus, having a gas inlet and a gas outlet, for detecting a false alarm is disclosed. The gas-detecting apparatus comprises a control module, a sensor module, and an air chamber. In an example embodiment, the sensor module is electrically connected with the control module. The sensor module has a sensor inlet and a sensor outlet. The sensor inlet is fluidly coupled to the gas inlet of the gas-detecting apparatus. The air chamber has an air inlet and an air outlet, wherein the air inlet is fluidly coupled to the gas inlet of the gas-detecting apparatus and the air outlet is fluidly coupled to the gas outlet. The control module is configured to receive a first sensing signal for a first level of gas from the sensor module and determine whether magnitude of the first sensing signal is higher than a first threshold value. In an instance when the magnitude of the first sensing signal is higher than the first threshold value, the control module causes the air chamber to supply ambient air to the sensor module through the sensor inlet of the sensor module.

A pressure detector that includes a case connectable to a flow route for liquid, and a membrane member provided in the case and with which a liquid-phase portion to be supplied with the liquid in the flow route and a gas-phase portion to be supplied with gas are separated from each other, the membrane member being displaceable in accordance with a pressure of the liquid supplied to the liquid-phase portion, the pressure detector detecting the pressure of the liquid in the flow route by detecting a pressure in the gas-phase portion. The gas-phase portion has an opening through which the gas is allowed to be introduced or discharged in accordance with the displacement of the membrane member, and a secured portion secured for the introduction or discharge of the gas through the opening during the displacement of the membrane member toward a side of the gas-phase portion.

Systems and methods for pressure measurement are provided. A ludion with a trapped gas bubble floats between two liquids. Pressure acting upon the liquids causes the bubble to expand or contract, resulting in movement of the ludion which can be measured and correlated with pressure change. Pressure measuring device can measure pressures from 0.05 inHg to 110 inHg with a four-to-one Test Accuracy Ratio (TAR) without using mercury.

A device for detecting a sudden pressure variation in a fluid, including a housing open at one of its ends, a wall closing the housing to create a chamber, the wall being configured such that, when the external pressure outside the chamber is substantially stable or varies slowly, the internal pressure of the chamber is close to the external pressure, and the wall having mechanical characteristics such that it breaks when subjected to a predetermined difference between the external pressure and the internal pressure.

An apparatus for measuring pressure is disclosed. The apparatus can be used to measure static pressures or dynamic pressures as would a conventional microphone, but can be integrated with antenna elements, and can be implemented without need for conductive elements in the array itself to provide the sensed pressure signal for processing. Instead, diaphragm movement is remotely and wirelessly sensed and used to determine pressure.