HT instruments GEO416 - Manual (Page 9)

GEO416 - GEO416GS
EN - 8
5. Extend, if necessary, the blue and red measuring cables separately using cables with
proper section. Adding any extension does not require calibration and does not affect
the measured earth resistance value
6.
Drive the auxiliary rods into the ground keeping to the distance instructions provided
by the standards (§ 11.2)
7. Connect crocodiles to the auxiliary rods and to the installation under test (see Fig. 3)
8. Press GO key, the instrument starts carrying out measurement
9. While the instrument is measuring a
screen similar to the one beside
appears where the instrument’s input
interfering voltage value is displayed.
When the message
is displayed
do not disconnect or touch the test
leads
Input interfering voltage
value
CAUTION
When starting measurement the input interfering voltage is measured at both
the volt and ampere circuit. Should it range between 3 V and 9 V, the
instrument carries out measurement and displays the symbol
indicating the
uncertainty decline of the measurement (§ 9.1)
10. When the test is over, should the earth
resistance value be lower than the full
scale, the instrument emits a double
tone indicating the positive outcome of
the test and displays the resistance
measurement as well as the interfering
voltage value at the time of measuring
Earth resistance
measurement
Input interfering voltage
value
CAUTION
The resistance measurement is effected with 4-wire volt ampere method
without being affected by the resistance value of the cables. It is therefore not
necessary to effect compensation of cable resistance or of any extension
11. When the test is over, should the earth
resistance value be higher than the full
scale, the instrument emits a long tone
indicating the negative outcome of the
test and displays the screen beside
Earth resistance value
higher than full scale
Input interfering voltage
value
12. The measurements can be stored pressing the SAVE key twice (§ 5.1)