Abstract: A measuring circuit which includes an evaluation circuit (13, 63); a sensing circuit (39, 40) having a sensing element (6, 55) configured to generate a measuring signal from a measuring object (7) and a transmission line (26, 69) for transmitting the measuring signal to the evaluation circuit (13, 63); and a test signal injection circuit (21) including a signal injector (12) and an injection line (20) connecting a signal output of the signal injector (12) with the sensing circuit (39, 40) for feeding a test signal into the sensing circuit (39, 40) such that the test signal is transmittable to the evaluation circuit (13, 63) over the transmission line (26, 69). The injection line (20) and the transmission line (26, 69) are advantageously interconnected in series via the sensing element (6, 55) such that the test signal can be fed through the sensing element (6, 55).

Abstract: A force sensor includes a transducer with a measuring element operatively connected to a measuring object for generating measuring signals of a force acting on the measuring object, and two in parallel transmission channels transmit mutually corresponding signals of the measuring signals independently from one another and connected in parallel to the same transducer. A test signal is evaluated in a transmission channel in which the test signal has been injected and in another transmission channel in which the test signal has not been injected. In another testing method, the transmitted signals are compared.

Abstract: A measuring circuit comprising an evaluation circuit (13, 63); a sensing circuit (39, 40) comprising a sensing element (6, 55) configured to generate a measuring signal from a measuring object (7) and a transmission line (26, 69) for transmitting the measuring signal to the evaluation circuit (13, 63); and a test signal injection circuit (21) comprising a signal injector (12) and an injection line (20) connecting a signal output of the signal injector (12) with the sensing circuit (39, 40) for feeding a test signal into the sensing circuit (39, 40) such that the test signal is transmittable to the evaluation circuit (13, 63) over the transmission line (26, 69). To provide the measuring circuit with an improved surveillance and/or testing operability, the invention suggests that the injection line (20) and the transmission line (26, 69) are interconnected in series via the sensing element (6, 55) such that said test signal can be fed through the sensing element (6, 55).

Abstract: A force sensor includes a transducer with a measuring element operatively connected to a measuring object for generating measuring signals of a force acting on the measuring object, and two in parallel transmission channels transmit mutually corresponding signals of the measuring signals independently from one another and connected in parallel to the same transducer. A test signal is evaluated in a transmission channel in which the test signal has been injected and in another transmission channel in which the test signal has not been injected. In another testing method, the transmitted signals are compared.

Abstract: The seismic mass (4) of an accelerometer that comprises at least one electromechanical transducer is stabilized in the direction perpendicular to the sensible axis by at least one laterally stabilizing element (8) arranged between the electromechanical transducer (9) and a structural element (7). This stabilization eliminates or at least drastically reduces any distortions of the measurement results provoked by transversal accelerations.

Abstract: A measuring circuit includes a symmetric transmission line connecting a transducer to a measurement amplifier and to a fault indicating signal amplifier, the transducer delivering symmetric input signals to amplifiers, the first amplifier delivering a measuring signal representing the difference of its input signals and the fault indicating signal amplifier delivering a fault indicating signal representing the sum of the input signals. An auxiliary signal injected to the terminals of the transducer the invention enables the measuring circuit to evaluate the quality of the measuring circuit during operation of the tested machine and also when the machine is at rest.

Abstract: A method and a system for measuring the mechanical vibrations of an object. In order to simplify the electronic circuit necessary for the measurement chain and to reduce its costs, this method and this system are characterized in that they comprise the processing of an input signal, representative of an acceleration or of a velocity related to a mechanical vibration of said object, said input signal having a frequency spectrum comprising a so-called low frequency band, situated below a so-called transition frequency, and a so-called high frequency band, situated above said transition frequency, said method and system carrying out said processing of said input signal by means of an electronic circuit for producing an output signal which, in said low frequency band, corresponds to the mathematical integral over the time of said input signal, and, in said high frequency band, corresponds to said input signal.

Abstract: A measuring circuit comprising a symmetric transmission line connecting a transducer to a measurement amplifier and to a fault indicating signal amplifier, the transducer delivering symmetric input signals to said amplifiers, the first amplifier delivering a measuring signal representing the difference of its input signals and the fault indicating signal amplifier delivering a fault indicating signal representing the sum of the input signals. An auxiliary signal injected to the terminals of the transducer the invention enables the measuring circuit to evaluate the quality of the measuring circuit during operation of the tested machine and also when the machine is at rest.