MI 3108 EurotestPV
Measurements
– a.c. LV installations
66
Figure 5.39: Resistance to earth, measurement of a lighting protection system
Earth resistance measurements, common measurement procedure
Select
EARTH
function using the function selector keys.
Enable and set
limit
value (optional).
Connect
test leads to the instrument.
Connect
the item to be tested (see figures 5.38, 5.39).
Press the
TEST
key to perform the measurement.
Store
the result by pressing the MEM key (optional).
Figure 5.40: Example of earth resistance measurement result
Displayed results for earth resistance measurement:
R.............. Earth resistance,
Rp............ Resistance of S (potential) probe,
Rc ............ Resistance of H (current) probe.
Notes
:
High resistance of S and H probes could influence the measurement results. In
this case, “Rp” and “Rc” warnings are displayed. There is no pass / fail indication
in this case.
High noise currents and voltages in earth could influence the measurement results.
The tester displays the
warning in this case.
Probes must be placed at sufficient distance from the measured object.