Sonel MPI-530-IT - Measurement of Resistance to Earth Using 4 P Method

OPERATING MANUAL MPI-530-IT version 1.06
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Additional information displayed by the meter
R
E
>1.99 kΩ
Measuring range is exceeded.
U
N
Voltage at test terminals is higher than 24 V but lower than
50 V, measurement is blocked.
U
N
>50V! and contin-
uous, modulated au-
dio signal
Voltage at test terminals is higher than 50 V.
NOISE!
Signal / noise ratio is too low (interfering signal too large).
LIMIT!
Error due to the resistance of electrodes > 30 % (for calcu-
lating uncertainty, measured values are taken into account).
Interruption in measuring circuit or resistance of test probes
is higher than 60 kΩ.
Electrode resistance
>50 kΩ
Resistance of electrodes within the range of 50...60 kΩ.
ABORTED
Measurement has been interrupted with ESC key button.
3.5.2 Measurement of resistance to earth using 4p method
Four-pole method is recommended for use in the measurement of earth resistance of very small
values. It allows user to eliminate the influence of resistance of test leads on the measurement re-
sults. To determine the soil resistivity, it is recommended to use a function dedicated for this meas-
urement (section 3.5.5).
Disconnect the tested earth elec-
trode from the system of the object.
The current electrode (driven into earth) should be connected to H socket of the meter.
The voltage electrode (driven into earth) should be connected to S socket of the meter.
The earth electrode being tested should be connected to E socket of the meter with the lead.
ES socket should be connected to the tested earth electrode below E lead.
The tested earth electrode as well as current and voltage electrodes should be located along one
line and in the relevant distances, in accordance with the rules of earth measurements.
Tested earth
electrode