Chauvin Arnoux C.A 6115N, Руководство пользователя

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9.2 Procedure
WARNING! Make sure that the electrical network is NOT live before making a continuity test with
the adapter unit.
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Method 1
To measure R1 + R2 only:
1) Implement a temporary Live-Earth link at the distribution board.
2) Plug the adapter unit into the outlet socket furthest away from the distribution board.
3) Select position A (L-E) on the adapter unit.
4) Make a low Ohms measurement with the C.A 6115N. This is the value of R1 + R2.
5) Disconnect the temporary link at the distribution board after the test.
Result: R1 + R2 = A
N.B. Lead resistance can be deducted from A, B & C, see below
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Method 2
To measure individual values for R1, R2 and R
neutral
:
1) Implement a temporary Live-Earth-Neutral link at the distribution board.
2) Plug the adapter into the outlet socket furthest away from the distribution board.
3) Select position A (L-E) on the adapter unit and make a low Ohms measurement and note the
reading.
4) Next, make a measurement with the switch in the B (L-N) position and note this reading.
5) Finally, make a measurement with the switch in the C (N-E) position and note this reading.
6) Disconnect the temporary link at the distribution board after the test.
9.3 Calculating values
The different values are calculated as below:
R1 + R2=A
R1 = (A + B - C)/2
R2 = (A - B + C)/2
R
neutral
= (B + C - A)/2
9.3.1 Deducting lead resistance
Below are typical lead resistance values that can be deducted from A, B & C:
- For A: 0.09 Ohms (typical)
- For B: 0.09 Ohms (typical)
- For C: 0.06 Ohms (typical)
It should be noted that the value of C may be higher or lower than A and B depending on the rating of the
fuse in the plug.
9.4 Comments on the 2 different methods
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Use method 1 for routine periodic inspections where it is necessary to record the actual value for
R1 + R2, although normally an Earth loop impedance measurement is sufficient, and arguably, is
a much better measurement to make.
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Method 2 may be used to test the continuity of conductors in a new installation and has the advantage
that a long lead of known resistance is not required (the use of this latter is not always practical,
especially when some circuits are located on a different floor from the distribution board). It also
avoids the needs to subtract the resistance of a long lead from each measurement.