Abstract: A pressure sensor includes a housing, a pressure chamber defined within the housing, and a pressure transducer. The pressure sensor also includes a header that seals the pressure chamber and supports the pressure transducer in the pressure chamber. A plurality of pins extend through respective openings in the header. The sensor pins have first ends electrically connected to the pressure transducer in the pressure chamber and second ends electrically connected to sensor electronics outside the pressure chamber. The pins are electrically insulated from the header. The header is configured so that the electrical insulation of at least one pin from the header is less than the electrical insulation of the remaining pins from the header.

Abstract: An apparatus for measuring flow in a conduit includes a sensor head configured for insertion transversely through a conduit sidewall to position the sensor head in an electrically conductive fluid flowing through the conduit. The sensor head includes a core and a coil that at least partially surrounds the core, the coil being excitable to generate an electromagnetic field. The sensor head also includes first and second electrodes spaced apart from each other, and a body that supports the coil, core, and electrodes. The body includes at least one channel through which the electrically conductive fluid flows. The electrodes are positioned in the at least one channel. Each channel is defined by opposing sidewalls that have a converging configuration.

Abstract: A method and apparatus for balancing terminals of an HVAC system uses an air flow measuring device by inputting into a computer processing portion of the air flow measuring device predetermined target flows for each terminal; acquiring via the air flow measuring device initially measured air flows through each of the terminals, the initially measured air flows being provided to the computer processing portion; and adjusting the terminals in the HVAC system to flow set points according to instructions from the computer processing portion, the computer processing portion being programmed to calculate the flow set point for each terminal given current HVAC system load conditions, that will result in all terminals being set to target flow after all terminals have been adjusted as instructed.

Abstract: An apparatus for measuring airflow in an airstream includes a generally planar panel adapted to be placed in the airstream so that air passes over opposite surfaces of the panel. The panel includes at least one slot that extends through the panel. A hot-point element is mounted on one of the panel surfaces adjacent the at least one slot. The at least one slot is configured to permit air passing over the opposite surfaces to pass through the slot and become mixed together. The hot-point element is positioned on the panel so that the mixed air passes over the hot-point element.

Abstract: An apparatus for obtaining pressure measurements in an airstream includes a Pitot tube. The Pitot tube includes at least one total pressure port configured to be positioned in the airstream facing upstream, at least one static pressure port configured to be positioned in the airstream facing downstream, at least one first directional port, and at least one second directional port. The at least one first directional port and the at least one second directional port are positioned on opposite sides of the at least one total pressure port and face obliquely with respect to the direction that the at least one total pressure port faces.

Abstract: A rotameter includes a rotameter body including an inlet, an outlet, and a flow channel that provides fluid communication between the inlet and the outlet. A valve for controlling fluid flow through the inlet includes an actuator rotatable about a first axis. The actuator includes worm gear threads. The valve also includes a valve drive element rotatable about a second axis that extends transverse to the first axis. The valve drive element includes worm gear teeth that mate with the worm gear threads on the actuator so that rotation of the actuator about the first axis imparts rotation of the valve drive element about the second axis. The valve drive element further includes first screw threads that rotate with the valve drive element about the second axis. The first screw threads are configured and arranged to mate with and engage second screw threads to cause linear movement of a valve component along the second axis in response to rotation of the valve drive element.

Abstract: A humidity sensor arrangement for providing temperature compensated measurements. A first sensor is configured internal to a housing for the sensor arrangement, and a second sensor is configured external to the housing. The first sensor measures a first relative humidity at a first temperature, and the second sensor measures second temperature external. A processor determines saturation pressures for the first and second sensors and compensates the first sensor by adjusting the relative humidity for the first sensor to be a product of the relative humidity for the first sensor and a ratio of the saturation pressure of the first and second sensors. Further compensation may be produced by applying a time-based filter algorithm to the outputs of the first and second sensors. Temperature sensors can be compensated to determine room temperature and compensated temp can be used for precise humidity compensation.

Abstract: An apparatus for measuring airflow through a diffuser of an HVAC system includes a hood for being positioned adjacent the diffuser so that airflow discharged from the diffuser is directed into the hood. The hood is configured to divide and direct the airflow through a plurality of discharge channels. Sensor probes measure the airflow through each discharge channel.

Abstract: A pressure transducer for a hammer union installation includes a lower body capable of withstanding the stresses of the hammer union installation. The lower body includes a cylindrical wall, a diaphragm, and a pressure port for exposing the diaphragm to pressure. The pressure transducer also includes one or more transducer elements mounted on the diaphragm that are operable to provide a signal related to pressure. A cap is received by the cylindrical wall and is slidable along the wall. The cap includes comprising an antenna for transmitting the signal. A spring is arranged in the lower body for dampening forces applied to the cap.

Abstract: An apparatus for monitoring air flow in a vent pipe of a radon mitigation system includes a base connectable to the vent pipe. The base houses a circuit that is actuatable to indicate the condition of the radon mitigation system. An air flow switch actuates the circuit, the air flow switch includes a vane that is supported by the base and extends into the interior of the vent pipe through an opening in a wall of the vent pipe. The vane includes a wing having portions that are deflectable to permit installation of the wing through an opening in the vent pipe. The deflectable portions return under their own resilience to their non-deflected conditions once they pass through the opening in the vent pipe.

Abstract: System, apparatus and method for providing corrective sensor outputs, particularly when a sensor is subject to gravitational or acceleration effects. A sensor and accelerometer may be operatively coupled to a processor, wherein the processor receives inputs from both. The processor receives the sensor signals and determines the gravitational or acceleration effects on the sensor from the accelerometer signals. Based on these, the processor determines a correction factor that is applied to the sensor signals to provide improved and more accurate sensor outputs.

Abstract: System, apparatus and method for capacitive sensing, where a sensor includes an upper and lower housing, each respectively equipped with upper and lower pressure ports. The lower housing is electrically coupled to an active shield. An insulating material is provided on or near a conductive diaphragm for insulating the conductive diaphragm from the lower housing. The insulating material may be an insulator or a dielectric material, where a sensing electrode is positioned such that the sensing electrode extends laterally across at least a portion of the insulating material, and is separated from the insulating material by a predetermined distance to form an air gap.

Abstract: A humidity sensor arrangement for providing temperature compensated measurements. A first sensor is configured internal to a housing for the sensor arrangement, and a second sensor is configured external to the housing. The first sensor measures a first relative humidity at a first temperature, and the second sensor measures second temperature external. A processor determines saturation pressures for the first and second sensors and compensates the first sensor by adjusting the relative humidity for the first sensor to be a product of the relative humidity for the first sensor and a ratio of the saturation pressure of the first and second sensors. Further compensation may be produced by applying a time-based filter algorithm to the outputs of the first and second sensors. Temperature sensors can be compensated to determine room temperature and compensated temp can be used for precise humidity compensation.

Abstract: Systems, apparatuses and methods are disclosure for adjusting and/or modifying outputs of sensors based on deadband effects, where sensor adjustments may be based on a value, which may be a constant, such as an error value for the sensor, or a dynamic value. Differential pressure values measured from the output of sensors are compared to the value, and, in response to the comparison, the output of the sensor may be set substantially to zero if the measured differential pressure value is less than the value. Otherwise, the measured differential pressure values are passed through if they are is equal to or greater than the value. Additional techniques employing zero offsets, span adjustment and error scale adjustments are further disclosed.

Abstract: System, apparatus and method for capacitive sensing, where a sensor includes an upper and lower housing, each respectively equipped with upper and lower pressure ports. The lower housing is electrically coupled to an active shield. An insulating material is provided on or near a conductive diaphragm for insulating the conductive diaphragm from the lower housing. The insulating material may be an insulator or a dielectric material, where a sensing electrode is positioned such that the sensing electrode extends laterally across at least a portion of the insulating material, and is separated from the insulating material by a predetermined distance to form an air gap.

Abstract: System, apparatus and method for providing corrective sensor outputs, particularly when a sensor is subject to gravitational or acceleration effects. A sensor and accelerometer may be operatively coupled to a processor, wherein the processor receives inputs from both. The processor receives the sensor signals and determines the gravitational or acceleration effects on the sensor from the accelerometer signals. Based on these, the processor determines a correction factor that is applied to the sensor signals to provide improved and more accurate sensor outputs.