Loop Measurement - Chauvin Arnoux C.A 6710 Notice De Fonctionnement

J
H
Loop measurements can be performed with the C.A 6115N and MX 4600.
Measurements possible:
Phase-neutral loop resistance
Phase-earth loop impedance and resistance
Short-circuit current
MEASUREMENT:
Set to the TT or TN neutral system (see § 3.1 and 3.2) .
If C.A 6115N, connect the measuring instrument to the safety terminals H (with the cable with 3 separate leads) or to mains
socket PR1 or PR2 (with the measurement cable fitted with a mains plug).
If MX 4600, use the cable fitted with a mains plug and connect it to socket PR1 or PR2.
Activate the measurements.
The earth loop measurement is used, particularly in urban environments, to measure the earths of buildings without
having to set up rods. Thanks to this demo case, you will notice that this is a measurement by excess which includes not only the
resistance of the earth to be measured but also the resistances of the wires and the earth connection of the distribution transformer
(whose very low value makes this type of measurement highly practical in the field).
The phase-neutral loop measurement is mainly used to evaluate the short-circuit current in order to choose the fuses or the circuit
breakers.
The earths E and ES can be set up in parallel to verify that the value of the global resistance diminishes.
A resistance in series with an inductance can be inserted in the PE conductor at the level of switch J to measure an impedance
rather than a resistance.
The C.A 6115N has "Phase-earth measurement = L-PE" and "Phase-neutral measurement = L-N" functions.

7. LOOP MEASUREMENT

Figure 6
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