Abstract: A method of configuring and synchronizing a wireless machine monitoring system that has at least one chain, that includes at least one machine monitor and at least one repeater is disclosed. The wireless machine monitoring system may further include a master repeater that is in communication with the chain and a command station that is in communication with the master repeater. The wireless machine monitoring system is configured so that only one element of the system is communicating at any given time. In addition, bit error rate transmission tests are performed on the elements of the system to determine their ability to communicate at different transmission power levels. Thus, power consumption of battery powered elements is minimized by decreasing the amount of time the devices are active and by configuring the communicating elements to transmit at the lowest acceptable power level.

Abstract: A monitor attaches to a machine or proximate a machine to determine the health and operating status of the machine. The monitor is preferably self-contained, having its own internal power source, electronics, and sensor suite. One or more sensors are provided to sense machine operating characteristics such as temperature, flux, and vibration. Sensor outputs are processed and analyzed by monitor electronics to determine various operating parameters, including machine speed and load, and to determine when an anomalous machine operating condition is present. Monitor electronics are operable to transform time domain data generated by the sensors to frequency domain data for storage and/or analysis. A communications port enables a peripheral device, such as a notebook computer or portable data collector, to communicate with the monitor and download stored data.

Abstract: A monitor attaches to a mount proximate a machine to determine the health operating history and operating status of the machine. The monitor is preferably self-contained, having its own internal power source, electronics, and sensor suite. If desired, the monitor may be powered by an external power source. One or more internal sensors disposed in the monitor are provided to sense machine operating parameters such as temperature, flux, and vibration. External sensors tethered to the monitor may be positioned at varying points on and/or in the machine. Monitor electronics process sensor outputs to determine machine operating parameters such as machine speed and load. Monitor electronics are also operable to transform time domain data generated by the sensors to frequency domain data. A communications port enables a peripheral device, such as a notebook computer or a computer network, to communicate with the monitor and download stored data.

Abstract: Power saving features are employed in a machine monitor to reduce electrical power consumption and increase the life of an electrical power source (such as a battery) which is used to power the monitor. The monitor includes a microcomputer having a high operating speed and a low operating speed. Power consumption is reduced by placing the microprocessor in a low-power sleep mode when full power capabilities of the microprocessor are not needed. Power consumption is further reduced by operating the microprocessor at the low operating speed when a high operating speed is not needed. The monitor also includes a communications port in electrical communication with the microcomputer for communicating with a peripheral device, and sensors for sensing machine characteristics such as speed, temperature, flux, or vibration.

Abstract: A programmable apparatus is used to determine the running speed of an ac induction motor based on vibration and flux measurements. A first analysis is performed on at least one of the vibration and flux signals according to a first criterion to determine candidate speeds and whether speed will be determined based on the first analysis or whether a second analysis is required. A second analysis is selectively performed if required by the first analysis. In the first analysis, vibration signals (for example) are transformed to the frequency domain, such as by Fast Fourier Transform, and vibration amplitude peaks contained in the resulting spectrum are analyzed to identify candidate peaks. If only one candidate peak is identified, the frequency at which the candidate peak occurs is used to determine motor running speed. If two or more candidate peaks are identified and the motor is a two-pole motor, the candidate peak having the maximum amplitude is used to determine running speed.

Abstract: A machine monitor provides information for ascertaining the health and condition of a machine. The monitor is self-contained, having its own internal power source, electronics, and sensor suite, and attaches directly to the outer frame of the machine. Sensors disposed within the monitor include a machine frame temperature sensor, flux sensor, vibration sensor, and clock. Electronics are also disposed within the monitor for receiving and processing sensor outputs, producing machine status data which is stored over time. Sensors and electronics are housed in a protective bucket which includes an upper housing element joined with a lower housing element. The monitor is attached to the machine in such a way that an engagement surface formed in the monitor establishes sensory contact with the machine, enabling machine sensors disposed in the monitor to sense the machine characteristics.

Abstract: A wireless machine monitoring and communication system includes one or more machine monitors which attach to one or more machines to sense a physical characteristic of the machine, such as vibration or temperature, and to produce wireless transmissions corresponding to the sensed characteristic. A command station executes machine status polling in accordance with a time-division communication protocol and processes machine status data obtained during polling to determine the status of the machine. The machine monitor incorporates a wireless transmitter for transmitting at least status information, and the command station incorporates a wireless receiver for receiving monitor transmissions. To conserve power, the machine monitors are turned on only at preprogrammed times in accordance with the time-division communication protocol. Each machine monitor includes a receiver and the command station includes a transmitter to enable the command station to send commands to each machine monitor.

Abstract: A hand held data collector and analyzer achieves superior stability, accuracy and reliability through the use of a fixed frequency anti-aliasing filter and two analog to digital converters, one for high frequency signals and one for low frequency signals. Efficient digital filtering and decimation is achieved by providing specialized hardware filters and decimators and implementing software filters and decimators in a data processor. A true zoom method is employed to take advantage of the filtering and decimation capabilities, and independent digital signal processors operate serially on incoming signals to further reduce demands on the central processing unit. In addition, the RAM system memory is formatted as a pseudo-card to facilitate use of a PCMCIA memory card or the RAM system memory.

Abstract: An apparatus is disclosed consisting of one or more machine monitors which attach to one or more machines to sense a physical characteristic of the machine, such as vibration or temperature, and produce wireless transmissions corresponding to the sensed characteristic, and a command station which receives the transmissions from the machine monitors and processes the information to give an indication of the condition of the machine. The machine monitor incorporates a wireless transmitter to transmit the sensor data, and the command station incorporates a wireless receiver to receive the sensor data. In the preferred embodiment of the invention, the machine monitors are not continuously on, but turn on only at preprogrammed times according to turn-on commands generated by a timer circuit within each machine monitor. In another preferred embodiment, each machine monitor includes a receiver and the command station includes a transmitter to enable the command station to send commands to each machine monitor.

Abstract: A monitor attaches to a mount proximate a machine to determine the health and operating status of the machine. The monitor is preferably self-contained, having its own internal power source, electronics, and sensor suite. One or more sensors are provided to sense machine operating characteristics such as temperature, flux, and vibration. Sensor outputs are processed and analyzed by monitor electronics to determine various operating parameters, including machine speed and load, which are stored in memory. Other parameters which can be calculated and stored include cumulative time of machine operation for different categories of loads, cumulative time of machine operation over a predetermined maximum temperature, and total number of machine starts. Monitor electronics are also operable to transform time domain data generated by the sensors to frequency domain data.

Abstract: An ac machine monitor, particularly applicable to ac induction motors, provides information for ascertaining the health and condition of the motor. The monitor is self-contained, having its own internal power source, electronics, and sensor suite, and attaches directly to the outer frame of the motor. Sensors disposed within the monitor include a motor frame temperature sensor, flux sensor, vibration sensor, and clock. The flux sensor includes a substantially planar substrate onto which a conductive trace is attached as the flux sensing element. Sensor outputs are processed and analyzed by monitor electronics to determine various life history parameters, including motor speed and load, which are stored in electronic memory. A communications port enables a peripheral device, such as a notebook computer or portable data collector, to communicate with the monitor and download the life history parameters stored in memory.

Abstract: An ac machine monitor, particularly applicable to ac induction motors, provides information for ascertaining the health and condition of the motor. The monitor is self-contained, having its own internal power source, electronics, and sensor suite, and attaches directly to the outer frame of the motor. Sensors disposed within the monitor include a motor frame temperature sensor, flux sensor, vibration sensor, and clock. An ambient temperature sensor enables determination of motor frame temperature relative to ambient. Sensor outputs are processed and analyzed by monitor electronics to determine various life history parameters, including motor speed and load, which are stored in electronic memory. A communications port enables a peripheral device, such as a notebook computer or portable data collector, to communicate with the monitor and download the life history parameters stored in memory.

Abstract: A zoom processor for increasing the resolution of a band of interest within an acquired analog time domain frequency signal. The signal is converted from an analog time domain signal to a digital time domain signal. Next, the signal is multiplied by a value which will lower the center frequency of the band of interest to zero. The value by which the signal is multiplied is based on both the sine and cosine of a function of the center frequency and the sampling frequency used to digitize the signal. The sine function is solved with the aid of a numerical substitution which simplifies finding the value of the function in a sine table. After the signal is shifted, it is low-pass filtered, which removes all of the signal except the band of interest. During filtering, the band is also decimated by a predetermined factor, which compresses the time domain signal, and proportionally expands the frequency domain signal which is produced at a later step of the method.

Abstract: A method for nonintrusive monitoring of slow speed machinery incorporates a high sensitivity accelerometer capable of detecting low level mechanical vibrations, and a standard data collector/analyzer for processing the accelerometer output in accordance with a slow speed technology (SST) methodology that is implemented by firmware or software. To prevent the high frequency components from overwhelming the low frequency components of the accelerometer output as a result of dynamic range loss during processing of the accelerometer output by the data collector/analyzer, the SST methodology converts the accelerometer output from the acceleration domain to the velocity domain with an analog integrator that amplifies the low frequency components of the accelerometer output while attenuating the high frequency components. The analog integrator distorts the low frequency vibration components as well as the electrical noise introduced by the accelerometer.

Abstract: A hand held data collector and analyzer achieves superior stability, accuracy and reliability through the use of a fixed frequency anti-aliasing filter and two analog to digital converters, one for high frequency signals and one for low frequency signals. Efficient digital filtering and decimation is achieved by providing specialized hardware filters and decimators and implementing software filters and decimators in a data processor. A true zoom method is employed to take advantage of the filtering and decimation capabilities, and independent digital signal processors operate serially on incoming signals to further reduce demands on the central processing unit. In addition, the RAM system memory is formatted as a pseudo-card to facilitate use of a PCMCIA memory card or the RAM system memory.

Abstract: A portable vibration monitoring device (10) for use in connection with a base computer (11) which stores data regarding the nature and parameters of vibration measurements to be made on preselected machines for predictive maintenance purposes. The device includes a power module (36) which energizes the various components. A vibration sensor (14) produces an analog signal which is representative of selected vibration parameters. The signal generated by the vibration monitor is conditioned by a signal conditioning module (16) which includes anti-aliasing filters which enhance the accuracy of the data collected. A multiple function module (18) includes various selectively energized modules which enhance the speed and reliability of the data collected. This data is analyzed by a microprocessor and displayed as desired.