HT instruments MACROTEST G3 - Manual (Page 60)

MACROTESTG3 - COMBIG3
EN - 59
6.7. EARTH: MEASUREMENT OF EARTH RESISTANCE
The MACROTESTG3, MOD1, MOD2 models (or COMBIG3 with EARTH function enabled)
allows performing the measurement of earth resistance of an installation in the following
ways:

Measurement of earth resistance with 3-wire or 2-wire voltammetric method
 Measurement of ground resistivity ( ) with Wenner 4-wire method
 Measurement of resistance of individual rods without disconnecting them by means of
the optional clamp T2100
6.7.1. 3-wire or 2-wire earth measurement and 4-wire ground resistivity
The measurement is carried out in compliance with standards IEC/EN61557-5.
CAUTION
 The instrument can be used for measurements on installations with
overvoltage category CAT III 240V to earth with a maximum voltage of
415V between inputs. Do not connect the instrument to installations with
voltages exceeding the limits indicated in this manual. Exceeding these
limits could result in electrical shocks to the user and damage to the
instrument.
 Always connect the measuring cables to the instrument and to the alligator
clips with the accessories disconnected from the system.
 We recommend holding the alligator clip respecting the safety area created
by the hand protection (see § 4.2).
 If the length of the cables supplied is not suitable for the installation under
test, you can create your own extensions following the indications in §
12.12.1.
Fig. 26: Three-wire earth resistance measurement