Earth Resistance Measurement (3-Pole Position); Important Remarks; Connections; Pre-Measurement Settings - Chauvin Arnoux CA 6470 Mode D'emploi

4-pole measurement
Measurement range
Resolution
Intrinsic error
Operating error

4.3 EARTH RESISTANCE MEASUREMENT (3-pole position)

The instrument measures the earth resistance of an installation with an AC current.

IMPORTANT REMARKS :

- Fast measurement : pressed briefly, the START pushbutton triggers the earth resistance measurement R
only.
- Expert measurement : pressed and held (2 seconds), the START pushbutton triggers the earth resistance
measurement R and the resistance measurement on the auxiliary rods R
E
4.3.1

CONNECTIONS :

4.3.2

PRE-MEASUREMENT SETTINGS

Before the measurement, use the
→ select the measurement mode, manual or automatic,
→ in automatic mode :
- select the voltage applied (16 or 32 V)
→ in manual mode :
- select the measurement performed (earth or earth coupling measurement),
- select the measurement frequency (41, 55, 92, 110, 119, 128, 476 Hz, or USr
- select the voltage applied (16 or 32 V)
(1)
The frequency "USr" is defined by the user for between 41 et 512Hz using the
In automatic or manual mode, the measurement frequency always returns to 128 Hz after the rotary
switch position has been changed. The voltage itself remains stored.
Notes :
→
In automatic mode, the instrument chooses the measurement frequency for which the possible
spurious voltage influence is minimal. If this influence affects the accuracy of the measurement, the
NOISE symbol flashes.
→
In manual mode, if the influence is too high for the selected frequency, the NOISE symbol flashes :
the frequency must always be changed to maintain measurement accuracy.
0.001 – 10.00 –
9.999Ω 999.9Ω
0.01 Ω
0.001Ω
± (2% + 3 pt)
± (5% + 5 pt)
R R
CONFIG CONFIG CONFIG
and keys to successively :
DISTANCE DISTANCE
44
100.0 – 1.000 –
999.9Ω 9.999kΩ
0.1 Ω 1 Ω
and R .
S H
H H
S S
E E
E E
(1)
)
keys.
10.00 -
99.99kΩ
10 Ω
E