Inductive sensor

About: Inductive sensor is a research topic. Over the lifetime, 2282 publications have been published within this topic receiving 21984 citations.

Vehicle detector system with presence mode counting

Abstract: A detector system filters the effects of periodic noise such as magnetic flux from nearby power lines or other periodic sources. The detector system further adapts in the case that the system incorporates microloops for the inductive sensors. The detector system further counts multiple vehicles while in presence mode. The detector system also logging of vehicle data and system faults.

Proximity sensor circuit with programmable logic device controller

Abstract: An improved proximity sensing circuit and method is provided. In particular, the proximity sensing system includes an improved controller comprising a programmable logic device ('PLD') [412]. In one particular aspect of the invention, the controller includes a field programmable gate array ('FPGA') controller. In general, the proximity sensing system measures the AC and DC resistances of a proximity sensor [402] and a precision resistor [404] and, from these measured values, calculates a compensated resistance. The compensated resistance may be used to determine the gap. The measured AC and DC resistances of the proximity sensor may be used to perform a self diagnostic on the sensing system and to aid in determining a system fault.

Ground loop detector circuit and method

Abstract: A ground loop detector circuit and method for an instrument that is used with either a pH sensor or a conductivity sensor. In the instrument used with a pH sensor, an AC diagnostic signal is provided to the sensor. A high input impedance diagnostic signal monitor monitors the voltage at a node adjacent the output of the diagnostic signal source. The occurrence of a ground loop causes the voltage at the node to drop. The instrument used with the conductivity sensor, not only monitors current returning to the diagnostic circuitry from the sensor but also uses a high input impedance monitor to monitor the current leaving the diagnostic circuit to the sensor. The relationship between the current from the sensor and the current to the sensor can be used to determine if a ground loop has occurred as such a loop will cause the current from the sensor to be less than the current to the sensor.

Integrated normal sensing and proximity sensing on a multi-dimensional sensor array

Abstract: Apparatuses and methods for coupling a group of sensor elements together in one mode to collectively measure a capacitance on the group of sensor elements, in addition to individually measuring a capacitance on each of the sensor elements in another mode The apparatus may include a processing device, and a plurality of sensor elements that are individually coupled in a first mode for normal sensing and collectively coupled in a second mode for proximity sensing

Temperature compensation of an inductive sensor

Abstract: This invention discloses an apparatus and method of determining the temperature of the core of an inductive coil sensor so that the effective inductance of the coil sensor can be temperature compensated to thereby provide an accurate measure of the level of fuel in a tank. The method comprises energizing the sensor with a prescribed voltage, de-energizing the sensor, measuring the resultant voltage across the sensor, and determining the core temperature from the measured resultant voltage across the sensor.