Abstract: A method for checking a signal path of a sensor circuit for a field device, wherein the signal path includes a transducer for outputting analog raw measured values, an analog-digital converter to convert the analog raw measured values into digital raw measured values, and a digital processor designed to further process the digital raw measured values, includes: interrupting the measuring mode; replacing the analog raw measured values at an output of the transducer by an analog check signal; passing the analog check signal through the signal path so that the digital processor determines a measured value corresponding to the analog check signal; checking the determined measured value with a comparison value determined for the signal path; and, if the measured value determined for the analog check signal is outside a defined tolerance range for the comparison value, identifying a change in the state of the signal path.

Abstract: Disclosed is a method of monitoring a condition of objects in a piping system in which each object has a surface exposed to a product flowing through a pipe in the piping system. The method allows for the condition of each object to be monitored whilst the object remains in place. The method includes repeatedly measuring a resonance frequency of an oscillatory element of a vibratory device that is installed in the pipe and that exhibits a susceptibility to an impairment caused by accretion, abrasion, and/or corrosion corresponding to the respective susceptibilities of the objects. The resonance frequency of the vibratory device is reduced by accretion and increased by corrosion and by abrasion of its oscillatory element. The method further includes monitoring the condition of the objects based on the measured frequencies.

Abstract: Disclosed is a method for measuring a fill level of a fill substance in a container. The method includes: transmitting a first signal toward the fill substance; receiving a first received signal after reflection of the first signal in the container; transmitting a second signal toward the fill substance, wherein the second signal has at least one defined property deviating from the first signal; receiving a second received signal after reflection of the second signal in the container; ascertaining a first fill level value based on the first received signal and a second fill level value based on the second received signal; and determining the first fill level value or the second fill level value as fill level when the first fill level value and the second fill level value agree. In this way, the fill level is determined in redundant manner.

Abstract: Disclosed is a method of monitoring a condition of objects in a piping system in which each object has a surface exposed to a product flowing through a pipe in the piping system. The method allows for the condition of each object to be monitored whilst the object remains in place. The method includes repeatedly measuring a resonance frequency of an oscillatory element of a vibratory device that is installed in the pipe and that exhibits a susceptibility to an impairment caused by accretion, abrasion, and/or corrosion corresponding to the respective susceptibilities of the objects. The resonance frequency of the vibratory device is reduced by accretion and increased by corrosion and by abrasion of its oscillatory element. The method further includes monitoring the condition of the objects based on the measured frequencies.