In an embodiment, an apparatus is disclosed that comprises a plurality of resistors arranged as a reverse bridge and configured to convert an input voltage to a scaled output voltage. The scaled output voltage is scaled to a target format based at least in part on a range of the input voltage and a fixed value of the plurality of resistors. The input voltage is generated based at least in part on at least one signal generated by a sensor based at least in part on a measurement of a property of a measurement target. At least one of the plurality of resistors has a resistance value of R and at least another of the plurality of resistors has a resistance value of R plus or minus ΔR.

In an embodiment, an apparatus is disclosed that includes a plurality of resistors arranged as a reverse bridge and configured to convert an input voltage to a scaled output voltage. The scaled output voltage is scaled to a target format based at least in part on a range of the input voltage and a fixed value of the plurality of resistors. The input voltage is generated based at least in part on at least one signal generated by a sensor based at least in part on a measurement of a property of a measurement target.

An automatic filtering method includes: a step of analyzing an input signal so as to obtain a frequency spectrum of the input signal; and a step of selecting, on the basis of the frequency spectrum, at least one filter from among a plurality of preset filters and filtering the input signal. The step of selecting includes determining, on the basis of the frequency spectrum of, a signal type in the input signal; selecting, on a basis of the signal type, a corresponding filter corresponding to the signal type; filtering the input signal with use of a first parameter of the corresponding filter and setting a second parameter for the corresponding filter on a basis of a result of the filtering; and filtering the input signal with use of the second parameter set for the corresponding filter. The method may ensure a filtering effect against noise.

An automatic filtering method and device includes a step of analyzing an input signal so as to obtain its frequency spectrum; and a step of selecting, on the basis of the frequency spectrum, at least one filter from among a plurality of preset filters and filtering the input signal. The method and device automatically use a suitable filter on the basis of the frequency spectrum and repeat simulation of automatic fine adjustment to ensure a filtering effect against noise.

A measuring transducer for converting an analog electrical input signal into an analog electrical output signal. The measuring transducer contains a detection apparatus for detecting an analog electrical input signal within a predetermined input measurement range, wherein the input measurement range of the measuring transducer is divided into n adjustable partial input measurement ranges and the output range of the measuring transducer is divided into n adjustable partial output ranges, where n is greater than 1. Further, an apparatus is provided for recognizing the partial input measurement range in which the detected analog electrical input signal lies. An imaging apparatus maps each partial input measurement range to a separate partial output measurement range of the n partial output measurement ranges. Another apparatus converts the detected analog electrical input signal into the associated analog electrical output signal depending on the recognized partial input measurement range.

A method for detecting and responding to disturbances in a HVAC system using a noisy measurement signal and a signal filter is provided. The method includes detecting a deviation in the noisy measurement signal, resetting the filter in response to a detected deviation exceeding a noise threshold, filtering the noisy measurement signal using the signal filter to determine an estimated state value, and determining that a disturbance has occurred in response to the estimated state value crossing a disturbance threshold. In some embodiments, the method further includes performing one or more control actions in response to the detection of a disturbance.