The rod vibrating level switch vibration is generated by the magnet and electromagnet set in the inspection tube, and the difference of the current flowing through the electromagnet is checked when there is a powder object and there is no powder object, and the inspection signal of the powder object is output. In case that the inspection part is not covered by powdery objects, etc.:
If alternating current is applied to the electromagnet set on the sensor, it will vibrate according to the working frequency. According to the limit change of the magnet, the back EMF generated in the electromagnet becomes the maximum. Judge that the inspection part is not covered by powdery objects. If the inspection part is covered by powder objects, etc., even if alternating current is applied to the electromagnet set on the sensor, it cannot vibrate according to the working frequency. For an electromagnet, there is no back EMF because the magnet is stationary. Judge that the inspection part is covered by powdery objects.
