Operating Mode; Measurement Of The Resistance Of An Earth Point - Chauvin Arnoux C.A 6423 Manual De Instrucciones

3.1 MEASUREMENT OF THE RESISTANCE OF AN EARTH POINT

To measure the resistance of an earth conductor, the so-called "62% method" is in general
recommended. This measurement requires the use of the items in the Earth Kit (see Ch.6:
TO ORDER).
Cut the power supply to the installation and disconnect it from the earth by
opening the earth bar!
1. Connect terminal E to the earth to be measured.
2. Check that the bar
3. Drive in (completely if possible) the input earth rod H at a distance "a" from the earth point
(E) to be measured.
Note: this distance is further for a deep and extended earth point (larger range of influence).
4. Drive in the rod S at 62% of the distance between the earth E and the rod H (the rods S,
H and the earth point must be in line).
5. Connect the rods to their respective terminals with the leads.
6. Press the "MEASURE" button
none of the three indicators are flashing, otherwise, check the wiring (see Ch.3.4: FAULT
SIGNALS) and make the measurement again.
Measurement of resistance of earth point
earth bar E
earth
point
0 %

3. OPERATING MODE

is not present between terminals S and H.
4
and hold the button during measurement. Check that
11
E S H
S''
52 % 62 % 72 %
17
S S'
H
100 %