Hand-Held Magnetic Field Meter Based on Colossal Magnetoresistance-B-Scalar Sensor

Abstract

This paper describes a newly developed hand-held magnetic field meter, which enables the measurement of the magnitude of pulsed, alternating, or permanent magnetic flux density in a range from 0.06 up to 10 T. The device measures the magnitude of magnetic flux density independent of the field direction (B-scalar) and its measurement frequency ranges from dc to 100 kHz. This magnetometer consists of a hand-held magnetic field measurement meter and a pluggable probe whose main element is a spintronic sensor based on the colossal magnetoresistance (CMR) phenomenon. The new design of a probe containing a temperature sensor and a CMR-B-scalar sensor made from two manganite films with different resistivity versus temperature dependences ensures a reduced response signal dependence on temperature and thus increased the accuracy of the measurements. The hand-held meter has a graphical color touch screen for the display of the waveforms and provides measurements without the use of external oscilloscopes or other analog graphing devices. This magnetometer can be used for various industrial and scientific applications such as for the investigation of high-power electrical motors, fast high electrical current transients appearing in cases of the commutation of pulsed power circuits, for the measurement of pulsed magnetic fields in magnetic coils, or for measuring the dynamics of magnetic fields during electromagnetic metal forming and welding.