The control of surface levels is implemented using vibration methods when it is necessary to ascertain if solid powder or granular substances are at their minimum or maximum depths.
They are used for level control in silos for the storage of animal feed, flour, sawdust, sand, cement, etc.; in installations involving the transportation, dosage, storage and processing of plastic materials or other bulk materials with a density greater than 30 g/litre and maximum particle size of 8 mm; in foundries and cement manufacturing facilities. Controllers based on this technique are suitable for use in contact with food.
Their operation is based on the activation of a vibrating fork having two rods that are activated by a piezoelectric source. When the vibrating fork comes into contact with the material to be controlled, the oscillation is damped, the resulting vibration reduction is detected electronically and a switching signal is generated.
These devices are very robust and are supplied in an aluminium case with AISI 316 stainless steel connections. They resist significant mechanical loads thanks to the limited extension of the vibrating fork, they are simple to use and do not require maintenance.