Hall element is a device that applies hall effect. The so-called Hall effect was discovered by American physicist Hall in 1879. It refers to the physical phenomenon of transverse potential difference when the magnetic field acts on the carriers in the current-carrying gold conductor and semiconductor.
When electric current through the metal foil, if the perpendicular to the direction of the current applied magnetic field, the two side of foil can appear horizontal potential difference, the hall effect in semiconductor is more obvious than metal foil films, and therefore the multi-purpose hall element semiconductor, which is mainly used for door, window in the field of security in place feeling, the camera rotation Angle and position of the high speed detection, etc.
Safety tube called fuse, fuse tube, it is to point to a kind of installation in the circuit, to ensure the circuit safe operation of the electrical components. The fuse tube is made of lead-tin alloy or lead-antimony alloy, which has the characteristics of low melting point, high resistivity and fast fusing speed.
Its circuit symbol is FU. Under normal circumstances, the fuse tube plays the role of connecting the input circuit in the switching power supply. Once overload or short circuit fault occurs, the current through the fuse tube exceeds the fuse current, the fuse is fused, the input circuit is cut off, so as to play the role of over-current protection. There are glass tube, ceramic tube, cylinder and so on.
Determine whether insurance tube fuse can be tested with multimeter buzzer, will play to the buzzer to block, multimeter, each in red and black pens and contact insurance tube (or two pins) on both ends of the metal, multimeter displays “1”, said insurance tube has fusing, if the multimeter shows “0”, buzzer sound way at the same time, the normal insurance tube.
When replacing the fuse, attention should be paid to cutting off the power supply of the equipment, selecting the correct opening model, and selecting the correct rated voltage and rated current. The base of the fuse must be cleaned to avoid poor contact with the fuse.