Insulation Resistance Measurement; Case 1: Measurement Of Insulation With A 2 Mω Resistance In Parallel With A Capacity Of 5 Μf; (Configuration Of Insulation Measurement Between Conductors); Case 2: Insulation Measurement In A Single-Phase Mains Socket (Configuration For Measurement Of The Insulation Of The Whole Installation In Relation To The Earth) - Chauvin Arnoux C.A 6710 Notice De Fonctionnement

4. INSULATION RESISTANCE MEASUREMENT

Insulation resistance measurements can be made using the following instruments:
- C.A 6115N
- C.A 6511/13
- C.A 6521/23/25/31/33
Case 1: Measurement of insulation with a 2 MΩ Ω Ω Ω Ω resistance in parallel with a capacity of 5 µF
4.1

(configuration of insulation measurement between conductors)

The 2 measurement terminals do not carry any voltage, even if the demo case is powered up and the input differential is set to I.
MEASUREMENT:
Connect the leads
- if C.A 6115N: use the cable with 3 separate leads and connect the instrument to the measurement terminals with lead L1/L
and lead L2/N connected to lead L3/PE.
- if C.A 6511/13 or C.A 6521/23/25/31/33: use the set of 2 red + black leads with banana plugs on the end.
transmit the test voltage (≤ 1000 V DC)
!
Caution: do not apply a voltage > 1200 V DC
and read off the result.
The measurement will take time to stabilize because, at the beginning, the measurement current is only used to charge the 5 µF
capacity.
This is representative of a measurement on very long cables in a building or on distribution lines, for example. In general, these
cables have a significant capacity which influences the insulation measurements.
4.2
Case 2: Insulation measurement in a single-phase mains socket (configuration for measurement of
the insulation of the whole installation in relation to the earth)
The two differential devices RDD1 and RDD2 must be set to O.
MEASUREMENT:
Use the same cords as in the previous case, fitted with the test probes at their ends.
Place the test probes between the phase-neutral, phase-earth or neutral-earth terminals of socket P>R1 or PR2 to measure the
resistances already placed between these different points in the case and which simulate insulation faults.
Note:
If the C.A 6115N is used, you can also use the measurement cable with mains plug which you can connect directly to the left-hand
socket on the case (PR1). Position of the switch on the instrument: R L-N-PE.
With the C.A 6115N, if the RDD2 differential device is not cut off (in position I), the terminals (G) are connected and the leakage
current is varied on socket PR2 using the associated potentiometer P, the insulation measured will vary according to the leakage
current defined.
CASE N°1
DDR 1
PR 1
CASE N°2
Figure 3
20
DDR 2
G PR 2
P