The present disclosure includes a method for monitoring the condition of a component of an electromechanical resonator having a piezoelectrical element which can be excited to mechanical vibration using an electrical excitation signal and the mechanical vibrations of which can be received in the form of an incoming electrical signal. The method steps performed at a first point and a second point in time, including determining an amplification factor of the electromechanical resonator, determining a mechanical quality resonator, and establishing an electromechanical efficiency resonator at least from the amplification factor and the mechanical quality. A change over time in the electromechanical efficiency is calculated from the first point to the second point in time, the change over time in the electromechanical efficiency is compared with a pre-definable threshold, and a condition indicator is determined from the comparison.

An apparatus for determining and/or monitoring the viscosity, the density and/or a predetermined filling level, having an excitation/receiving unit which excites a mechanically vibratable unit to vibrate, wherein a control/evaluation unit which is connected to the excitation/receiving unit and has a measuring branch and a checking branch separate from the latter is provided. The checking branch is configured to apply an excitation signal to the excitation/receiving unit, to receive the vibrations of the mechanically vibratable unit and to determine at least a first malfunction and a second different malfunction of the mechanically vibratable unit and/or of the excitation/receiving unit from the received vibrations, wherein the excitation signal of the checking branch has a continuous changing frequency which is described by a frequency/time function and passes through a plurality of modes of the mechanically vibratable unit.

A sensing structure in an example may include at least three electrodes along an interior surface of a reservoir from a top portion of the reservoir to a bottom portion of the reservoir wherein at least one of the electrodes is closer to at least another electrode at the top portion of the reservoir than at the bottom portion of the reservoir.

A method and system are described for detecting a fault of a fluid level sensing device associated with an aircraft engine, the fluid level sensing device arranged to measure a variance in a fluid level. The method comprises triggering a timer, while the timer is running, receiving a measurement indicative of the fluid level from the fluid level sensing device, resetting the timer when at least one timer-reset condition has been met, and outputting a fault signal when the timer reaches a timer 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.

In one example a fluid level sensing device is described. The device includes a sensing die having a number of fluid level sensors disposed thereon and a number of control devices, each control device corresponding to one of the number of fluid level sensors. A control device includes a comparing device to determine a state of a corresponding fluid level sensor. A state of the fluid level sensor is selected from the group consisting of a fluid state and a no-fluid state. Each control device also includes a non-volatile memory device corresponding to the comparing device to indicate whether the corresponding fluid level sensor is at the fluid state or the no-fluid state. A control device also includes a locking device to irreversibly set the non-volatile memory device to the no-fluid state independent of a write command from a controller.

An exemplary fill level measurement device comprising a radar module can be provided, along with method, computer-executable instructions and computer-readable medium. The radar module can comprise a receiving channel for receiving a radar signal reflected by a filling medium. The fill level measurement device can also comprise a test module for testing the functionality of the receiving channel. The test module can comprise a test input (for feeding in a test signal having a test frequency, and a feeding-in apparatus configured to feed at least part of the test signal into the receiving channel. The feeding-in apparatus can be configured to superpose and/or combine the test signal with the radar signal reflected by the filling medium. The receiving channel of the radar module can further comprise a mixing device having an intermediate frequency output. The mixing device can be configured to output the test frequency of the test signal at the intermediate frequency output when the receiving channel is functioning correctly.

The disclosure is related to a method for verifying an immersion cooling system. The immersion cooling system includes a first sensor, a second sensor and at least one third sensor. The method includes: obtaining a first difference value; determining whether the first difference value is smaller than a first threshold value; determining that the first sensor and the second sensor are in normal operation when the first difference value is smaller than the first threshold value; when the first difference value is not smaller than the first threshold value, determining an operating condition of the first sensor or the second sensor according to a relationship between a sensor value of the at least one third sensor and the sensor value of the first sensor, or a relationship between the sensor value of the at least one third sensor and the sensor value of the second sensor.

A method of diagnosing level sensor failure in a fuel cell water trap, the method may include: determining whether a water level of a level sensor is changed in a fuel cell water trap, adding an amount of charge according to an operating time and comparing the added amount of charge with a preset threshold amount of charge, according to the result of the forcibly opening a drain valve according to determining whether a channel voltage of a specific channel is abnormal as the result of the comparison, and diagnosing a failure of the level sensor according to determining whether the channel voltage of the specific cell is recovered as a normal state when the drain valve is opened.

The present invention relates to a method for monitoring state of a coil having at least two connection wires, which coil is part of an apparatus for determining at least one process variable of a medium in a containment, as well as relating to an apparatus for executing the method. The method, in such case, includes method steps as follows: ascertaining a desired-value of an ohmic total resistance for the coil and the connection wires, supplying the coil with an electrical excitation signal and receiving an electrical, received signal from the coil by means of the two connection wires, ascertaining an actual-value of the ohmic total resistance based at least on the received signal, and comparing the actual-value with the desired-value and ascertaining a state indicator based on the comparison.