A speed sensor arrangement, implemented in particular as a wheel rotation speed sensor arrangement, including: a sensor and a ferromagnetic encoder. The sensor has at least one magnetic field sensor element and a signal processing circuit. The speed sensor arrangement having a permanent magnet and the magnetic field provided by the permanent magnet is modulated by the ferromagnetic encoder at least during a movement of the encoder and the magnetic field sensor element of the sensor detects this modulated magnetic field. The magnetic field sensor element is implemented as a GMR sensor element or as a TMR sensor element and the speed sensor arrangement is implemented such that the permanent magnet is arranged at a defined minimum distance from the magnetic field sensor element.

A speed sensor arrangement, implemented in particular as a wheel rotation speed sensor arrangement, including: a sensor and a ferromagnetic encoder. The sensor has at least one magnetic field sensor element and a signal processing circuit. The speed sensor arrangement having a permanent magnet and the magnetic field provided by the permanent magnet is modulated by the ferromagnetic encoder at least during a movement of the encoder and the magnetic field sensor element of the sensor detects this modulated magnetic field. The magnetic field sensor element is implemented as a GMR sensor element or as a TMR sensor element and the speed sensor arrangement is implemented such that the permanent magnet is arranged at a defined minimum distance from the magnetic field sensor element.

Method of determining a position of a sensor device relative to a magnetic source, includes: a) determining a first and a second magnetic field component at a first sensor location; b) determining a third and a fourth magnetic field component at a second sensor location; c) determining a first difference of the first and third component, and determining a second difference of the second and fourth component, and determining a first angle based on a ratio of the first and second difference; d) determining a first sum of the first and third component, and determining a second sum of the second and fourth component; e) determining a second angle based on a ratio of said first and second sum; f) comparing the first and second angle to detect error.

Method of determining a position of a sensor device relative to a magnetic source, includes: a) determining a first and a second magnetic field component at a first sensor location; b) determining a third and a fourth magnetic field component at a second sensor location; c) determining a first difference of the first and third component, and determining a second difference of the second and fourth component, and determining a first angle based on a ratio of the first and second difference; d) determining a first sum of the first and third component, and determining a second sum of the second and fourth component; e) determining a second angle based on a ratio of said first and second sum; f) comparing the first and second angle to detect error.

A processing device (120) of a tire state detection system (100) is provided with an acceleration data acquisition unit (123) for acquiring the acceleration data detected by an acceleration sensor (111) at every predetermined acquisition interval, an acceleration data extraction unit (125) for extracting the maximum acceleration data indicating at least the maximum acceleration and the intermediate acceleration data indicating the intermediate acceleration excluding the minimum acceleration data indicating the minimum acceleration from 3 or more acceleration data acquired sequentially, and a calculation unit (127) for executing an calculation using the extracted intermediate acceleration data.

A processing device (120) of a tire state detection system (100) is provided with an acceleration data acquisition unit (123) for acquiring the acceleration data detected by an acceleration sensor (111) at every predetermined acquisition interval, an acceleration data extraction unit (125) for extracting the maximum acceleration data indicating at least the maximum acceleration and the intermediate acceleration data indicating the intermediate acceleration excluding the minimum acceleration data indicating the minimum acceleration from 3 or more acceleration data acquired sequentially, and a calculation unit (127) for executing an calculation using the extracted intermediate acceleration data.

An encoder includes a base section, a spindle gear attached to a turning shaft section, a counter-shaft gear configured to mesh with the spindle gear and including a cylindrical gear section, a magnet provided in the counter-shaft gear, and an annular bearing member provided in the base section and configured to support the counter-shaft gear. When a straight line extending along the shaft section is represented as a first axis and a straight line orthogonal to the first axis is represented as a second axis, the magnet is disposed to overlap the bearing member in a plan view from a direction in which the second axis extends.

A cooling fan monitoring circuit for monitoring and immediately alerting the user of the activation of a cooling fan motor and blade assembly providing notice of the shutting down of equipment requiring cooling to prevent overheating and damage to the equipment. The circuit is capable of monitoring multiple cooling fans and shuts down equipment if any one of the cooling fans ceases function, fails a preset condition, or the equipment reaches a preset temperature.

A cooling fan monitoring circuit for monitoring and immediately alerting the user of the activation of a cooling fan motor and blade assembly providing notice of the shutting down of equipment requiring cooling to prevent overheating and damage to the equipment. The circuit is capable of monitoring multiple cooling fans and shuts down equipment if any one of the cooling fans ceases function, fails a preset condition, or the equipment reaches a preset temperature.

The present disclosure relates to systems and methods for improved anomaly detection for rotating machines. An example method may include determining a rotational speed of a rotating machine; determining, using a frequency domain transform of a signal, a frequency domain signal; determining, based on the rotational speed, a first frequency band within the frequency domain signal for identifying a fault frequency; determining a fault frequency within the first frequency band; determining, based on the fault frequency, a second frequency band within the first frequency band, wherein the second frequency band includes the fault frequency; determining, based on the second frequency band, a first fault index and a baseline of the first fault index; determining, based on a deviation of a second fault index from the baseline, a fault condition; and providing an alert based on the fault condition.