Chauvin Arnoux CA 6471 [P01126505] Earth and Resistivity Tester. The Chauvin C.A 6471 earth tester is a complete portable measuring device intended for earth measurements and soil resistivity measurements. It is contained in a housing suitable for field use and supplied by a rechargeable battery with built-in charger. Ergonomic, comprehensive and accurate, the C.A 6471 offers direct access to all the measurements on the front panel by means of a rotary switch. Compact because it has been designed for on-site use, the C.A 6471 is rugged and leakproof. The 3P method is the traditional method using rods to measure the resistance of an existing earth connection. The C.A 6471 can also be used to measure the resistances of the auxiliary rods RS and RH, as well as any disturbance voltages. Suitable for all types of measurement environments, even the most difficult, this method guarantees  measurement of auxiliary-rod resistances up to 100 kΩ and disturbance voltages of 60 Vpeak. The 4P measurement method is particularly suitable for measuring very low earth resistances. If there are several resistances connected in parallel, it is possible to use the instrument with a clamp-on ammeter to carry out selective measurements, in order to avoid the effect of the parallel earth connections. This "selective 4P" measurement method saves considerable time because it is no longer necessary to disconnect the earth resistance before measuring it. In the event of a system with parallel earth connections, 2 clamp-on ammeters can be used with the .C.A 6471 to provide accurate earth resistance measurements. The C.A6471 automatically calculates soil resistivity using the Wenner or Schlumberger methods as soon as the distances between the rods have been entered.