In very long distances, complex solid or when we can not access directly to the tank, the measurement LASER devices offers a reliable and accurate solution.
Generally applied in solids, it is based on the principle of flight time, i.e. the time that the to bounce off the measuring point and return.
We can apply it directly on top of the tank, placing it far ahead of the measured product (e.g. products at high temperature) or measure through a peephole (when we can not access inside). We can obtain an analogic output or digital output of the level in mot of the cases.