Choose a static or dynamic penetrometer
Choice is not easy, but in principle the criterion of choice is bound by the types of land that it is usually necessary to investigate.
The dynamic test allows to exert greater drilling energies while the static test is linked to the available thrust contrast system.
In addition, the dynamic test provides only one value (strokes) for advances of 10/20 / 30cm while the static test provides 2 values (tip and side) for a feed of 20cm.
The dynamic test returns only the number of strokes (in this case the difference between a loose sand and an over-consolidated clay is difficult to determine) while the two values of the static test reading allow to identify the cohesive / granular nature of the investigated soil.