Abstract: Useful and meaningful machine characteristic information may be derived through analysis of oversampled digital data collected using dynamic signal analyzers, such as vibration analyzers. Such data have generally been discarded in prior art systems. In addition to peak values and decimated values, other oversampled values are used that are associated with characteristics of the machine being monitored and the sensors and circuits that gather the data. This provides more useful information than has previously been derived from oversampled data within a sampling interval.

Abstract: A machine condition monitor resides in close proximity to a machine train, such as an AC inductive electric motor coupled to a driven unit such as a centrifugal pump or fan. A plurality of sensing devices are connected to the machine and the machine condition monitor. Machine state and condition parameters sensed by these devices are utilized by the machine condition monitor to derive machine condition values for each component and for the machine train as a whole. These derived condition values are transmitted via an industrial communications network to a control center where they can be trended and monitored. With no particular knowledge of machine analysis techniques or severity of specific machine faults, and no special training, Operators and Production Planners can use the condition values to plan production schedules, adjust process parameters, and request appropriate maintenance action.

Abstract: The present invention provides a system and method for monitoring an electrical signal appearing on a rotating machine shaft. The system comprises a probe assembly for placement against the rotating machine shaft that is in electrically conductive contact with the shaft. The probe assembly includes at least one circuit for receiving the electrical signal from the rotating machine shaft and producing various electrical signals that are read by a data processing system, which is coupled to the circuit. The data processing system determines from the electrical signal obtained from the circuit, the RMS AC voltage, DC voltage, peak voltage, and the RMS AC and DC current through two different resisters that are all appearing on the rotating machine shaft. The data processing system also performs Fast Fourier Transforms on the RMS voltage and current signals and produces a frequency spectrum over time.

Abstract: Apparatus which automates the collection of motor temperature, flux and shaft current data for proactive motor maintenance. Motor speed is determined by an analysis of the flux frequency spectrum, and motor load is determined based on speed, from which a normalized thermal parameter is then determined. From a spectrum analysis of magnetic flux signals a set of peaks each characterized by a frequency and an amplitude is found, and a subset of peaks is identified in accordance with predetermined identity criteria for purposes of comparison. Temperature, magnetic flux and shaft current data are trended to provide early indications of degradation, as well as for recognizing faults.

Abstract: Apparatus for determining the rotational speed of an AC induction motor based on a spectrum analysis of a magnetic flux signal. For a Phase I analysis, which is usually sufficient, three sets of families of peaks indicative of possible rotational speeds are defined, and the flux frequency spectrum is searched for peaks meeting the family definitions to determine candidate speeds, and to assign scores. If there is a candidate speed with an overall score which exceeds a predetermined threshold, the motor rotational speed is determined as that candidate speed. A Phase II analysis, employing a more exhaustive set of five additional family definitions, is applied when Phase I fails to reach a result.

Abstract: The specification describes a system for analyzing and processing an input analog signal. This invention provides an analog signal preprocessor which is operated in conjunction with a main instrument for measuring any defects or wear of machinery parts. The analog signal preprocessor operates to preprocess an analog signal by filtering and amplifying a signal from the analog signal to allow a more accurate reading by the main instrument. The preprocessor will adjust itself for optimum operation and communicate the operation modes to the main instrument. Also, the preprocessor can be addressed by the main instrument to setup the operation of the preprocessor according to a program or input entered into the main instrument.