When it is possible to choose the position of the earth connection, resistivity measurement helps to assess the ground and thus determine the place where the earth resistance will be lowest (optimization of construction costs). The C.A 6472 automatically calculates the resistivity of the ground using the Wenner or Schlumberger method, as soon as the distances used between the rods have been entered. The resistances of the rods RE, RES, RS and RH can also be measured.
High-voltage lines are usually equipped with an earth cable to allow lightning to discharge to earth via the pylons. As all the pylons are connected to this conductor, all the pylons' earth resistances are in parallel. This means that it is impossible to measure pylon resistance using traditional 3P methods unless the earth cable is disconnected, which is a dangerous and time-consuming operation.