A physical quantity detection device including a container that accommodates a detection object formed of a dielectric, a first electrode provided at an outer side of the container, a second electrode that is provided separately from and to face the first electrode, and an electrostatic capacitance detector that detects an electrostatic capacitance between the first electrode and the second electrode. The electrostatic capacitance detector includes a waveform generation source coupled to the first electrode and a voltage detection circuit coupled to the second electrode. A relationship of |Zc|/|Z1|+|Zc|>|Zc|/|Z2|+|Zc| is satisfied in which |Zc| is an absolute value of an input impedance of the electrostatic capacitance detector, |Z1| is an absolute value of an impedance when the detection object is present between the first electrode and the second electrode, and |Z2| is an absolute value of an impedance when no detection object is present between the first electrode and the second electrode.

A physical quantity detection device including a container that accommodates a detection object formed of a dielectric, a first electrode provided at an outer side of the container, a second electrode that is provided separately from and to face the first electrode, and an electrostatic capacitance detector that detects an electrostatic capacitance between the first electrode and the second electrode. The electrostatic capacitance detector includes a waveform generation source coupled to the first electrode and a voltage detection circuit coupled to the second electrode. A relationship of |Zc|/|Z1|+|Zc|>|Zc|/|Z2|+|Zc| is satisfied in which |Zc| is an absolute value of an input impedance of the electrostatic capacitance detector, |Z1| is an absolute value of an impedance when the detection object is present between the first electrode and the second electrode, and |Z2| is an absolute value of an impedance when no detection object is present between the first electrode and the second electrode.

An optical level measuring device configured to measure a fill level of a medium through the container wall of a plastic container, having an optical distance sensor as well as a radar sensor.

A fuel management system to improve accuracy of calibration data to convert an output value of a fuel gauge into a remaining amount of fuel in a fuel tank includes a fuel tank mounted on a hull of a marine vessel, a fuel gauge to measure a liquid level position of fuel in the fuel tank, and a controller configured or programmed so that in a range where an output value of the fuel gauge changes, measurement reference points are set based on the output value of the fuel gauge. When supplying fuel to the fuel tank, the controller is configured or programmed to obtain calibration data showing a relationship between the output value of the fuel gauge and a remaining amount of the fuel in the fuel tank by comparing an amount of fuel supplied to the fuel tank at each of the measurement reference points and the output value of the fuel gauge at each of the measurement reference points.

A fuel management system to improve accuracy of calibration data to convert an output value of a fuel gauge into a remaining amount of fuel in a fuel tank includes a fuel tank mounted on a hull of a marine vessel, a fuel gauge to measure a liquid level position of fuel in the fuel tank, and a controller configured or programmed so that in a range where an output value of the fuel gauge changes, measurement reference points are set based on the output value of the fuel gauge. When supplying fuel to the fuel tank, the controller is configured or programmed to obtain calibration data showing a relationship between the output value of the fuel gauge and a remaining amount of the fuel in the fuel tank by comparing an amount of fuel supplied to the fuel tank at each of the measurement reference points and the output value of the fuel gauge at each of the measurement reference points.

A method carried out using a radar level gauge system, the tank having a tank roof supporting the radar level gauge system, a tank wall, and a tank atmosphere in a space defined by a surface of a product in the tank, the tank roof, and the tank wall, wherein the method comprises generating and transmitting an electromagnetic first transmit signal; propagating the first transmit signal through the tank atmosphere towards a corner reflector formed by the surface of the product and the tank wall where the surface of the product meets the tank wall, the corner reflector being at a known horizontal distance from the radar level gauge system; receiving an electromagnetic first reflection signal resulting from reflection of the first transmit signal at the corner reflector; and performing a filling level determination and/or a verification operation for the radar level gauge system based on a timing relation between the first transmit signal and the first reflection signal, and the known horizontal distance between the radar level gauge system and the corner reflector.

A method for checking operability of a first metering unit includes sending a control signal to a second metering unit to dispense a second quantity; comparing the quantity dispensed with the second quantity; sending a control signal to a second metering unit to introduce a third quantity; detecting the pressure drop caused by the introduction of the third quantity; sending a control signal to the first metering unit to introduce a first quantity; detecting the pressure drop caused by executing the control signal to introduce the first quantity; and ascertaining that the first metering unit is not functioning correctly if a difference between the pressure drop detected as a result of the execution of the control signal to introduce the first quantity and the pressure drop detected as a result of the execution of the control signal to introduce the third quantity is above a threshold.

A perfusion system includes a fluid reservoir configured to hold a portion of fluid, the portion of fluid having a volume, the fluid reservoir having a total capacity that is greater than the volume; an imaging device, the imaging device configured to obtain image data corresponding to the fluid reservoir; and a controller. The controller is configured to receive the image data from the imaging device; determine the volume based on the image data; and facilitate control, in response to at least one of a user input and the determined volume of the portion of fluid, of an operating parameter corresponding to the fluid reservoir to facilitate changing or maintaining the volume of the portion of the fluid.

A perfusion system includes a fluid reservoir configured to hold a portion of fluid, the portion of fluid having a volume, the fluid reservoir having a total capacity that is greater than the volume; an imaging device, the imaging device configured to obtain image data corresponding to the fluid reservoir; and a controller. The controller is configured to receive the image data from the imaging device; determine the volume based on the image data; and facilitate control, in response to at least one of a user input and the determined volume of the portion of fluid, of an operating parameter corresponding to the fluid reservoir to facilitate changing or maintaining the volume of the portion of the fluid.

There is disclosed a sensor system for determining a fluid level comprising a first sensor comprising a contact sensor a second sensor comprising a conductive sensor and a transducer configured to determine a water level based upon pressure placed on the transducer. There is also a microprocessor in communication with the first sensor, the second sensor and the transducer, the microprocessor configured to determine from at least one of the first sensor, the second sensor and the transducer, a fluid level in a container. In one embodiment the system further comprises a memory configured to feed values to the microprocessor, wherein the values comprise at least one of a high level fluid value and a low level fluid value. In one embodiment the microprocessor is configured to read pressure levels from the transducer wherein the pressure level of the transducer is configured to estimate a fluid level in a container.