What is a Hall probe?
The Hall probe identifies the magnetic flux density of a magnetic product or magnet. If you need more information, please contact IMA.
General on the Hall probe
The strength of a magnetic field must be detectable and quantifiable in terms of its size and intensity. A Hall probe can detect an essential characteristic of a magnetic field, magnetic flux density, in terms of size. Magnetic flux density indicates the degree of magnetization of a magnetic material. The Hall probe uses the Hall effect. When an electron motion through the magnetic field occurs perpendicular to the magnetic flux density of a magnetic field, the electrons experience a deflection by Lorentz force perpendicular to their direction of motion and perpendicular to the magnetic field. As a result of this deviation, the Hall voltage is produced in the Hall probe, which now serves as a measure of the strength of the magnetic field.
Function of the Hall probe in the field of magnetism.
An essential component of a Hall probe is a wafer made of a semiconductor material, which is passed through by an auxiliary current. The plate is arranged vertically in the magnetic field to be measured. The auxiliary current causes a movement of the electrons as charge carriers in the platelets. However, electrons deviate during their movement perpendicular to their direction of motion and perpendicular to the magnetic flux density due to the Lorentz force. This deviation creates a voltage gradient towards the opposite side due to the accumulation of moving load carriers on one side. This voltage gradient generates as a measurable amount the Hall voltage, which allows a conclusion about the magnetic flux density by means of a conversion. The force of Lorentz is defined by:
F = qv XB
There the product qv is the charge q moves in the magnetic field multiplied by its velocity v. B is the magnetic flux density. Since the mobile charge q consists of electrons negatively charged with the elemental charge e, the product qv is also negative. It is easy to see that a moving load with a positive sign would turn the Lorentz force direction 180° in the opposite direction. From this finding it is clear that the use of the Hall probe as a magnetic flux density measuring device is only one application. From the detection of the direction of force by the Hall probe it can also be concluded whether the moving loads are positively or negatively charged. Each permanent magnet, once magnetized, is measured with a Hall probe for an accurate recording of the magnetization characteristic.
Magnetic fields and Hall probe suppliers.
At the bottom of the Hall voltage, there is a direct proportionality between the auxiliary current I flowing through the semiconductor plate of the Hall probe and the magnetic flux density. The magnetic flux density flows vertically through the semiconductor chip, whose geometry, however, plays a decisive role in this process. In the roughly linear region of the magnetization characteristic, the density of the magnetic flux is roughly proportional to the Hall voltage being produced. Only in the field of determination of the magnetizing characteristic, the Hall probe has become an indispensable aid. To answer and clarify any outstanding questions about the Hall probes you receive from us. Contact us at any time. We are pleased to help you with all our experience in this complex field of magnetic engineering with help and advice.
The essential characteristic of each permanent magnet is its magnetizing characteristic. You can see in this characteristic curve exactly where the saturation point B S in the positive range and also the saturation point B S in the negative range. There is a distinction between magnetically hard materials and magnetically soft materials. The difference lies in the size of the coercive force, which establishes the extent to which the magnetic field strength must be applied in the negative direction to reduce the remanence of the permanent magnet to zero. With the Hall probe, the density of the magnetic flux in the magnetic fields can be accurately detected.