Measurement Probes; General; Specifications; Electrical Specifications - Chauvin Arnoux C.A 41 Mode D'emploi

MEASUREMENT PROBES

GENERAL

The measurement of an electric field works on the same principle as an aerial which picks up
a radioelectric signal. The sensitive part of the aerial is a detection cell with a very low threshold.
This DC signal resulting from the detection is transmitted to the measurement instrument
by a resistive line ensuring maximum transparency that does not disturb the electrical
field in which the instrument and its aerial is immersed.
The EF1 probe supplied with the C.A 41
is of the dual pole type.
The measurement is anisotropic;
reception is only via the vertical polari-
sation. Consequently, the reception
diagram in the horizontal
plane is circular.
In the vertical plane, the reception
diagram conforms to the pattern shown
below.
USING THE EF1 PROBE
Because of the anisotropy of the measurement probe, during measurement in a given
atmosphere, the aerial must be moved in all planes, along all axes.
We recommend using the Record function which after inspection will give the minimum,
maximum and average values of the field measured.
Before switching OFF the recording, it is necessary to HOLD the measurement using the HOLD
function. This makes it possible to memorise the different parameters before exiting the field.
Not using the HOLD recording function before exiting the field would risk introducing into the
memory values outside the field which would introduce errors into the measurements.
USING THE EF2 PROBE
As the EF2 probe is isotropic, it does not require special handling. Its sensitive part measures
the field according to 3 axes without the aerial having to be moved in the 3 planes. As for the
EF1 probe (see above), we recommend using the record function.
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SPECIFICATIONS

ELECTRICAL SPECIFICATIONS

Specified measurement range
MEASUREMENT EXTENT
RESOLUTION
ACCURACY
SAMPLING TIME
DIGITAL MEASUREMENT TIME
ANALOGUE MEASUREMENT TIME
STABILITY
Reference conditions
Distortion magnitudes Reference conditions
Ambient temperature
Relative humidity
Battery voltage
Measurement frequency
Field level
Accuracy of the measurement in the reference conditions : ≤ 0.5 V/m ± 0.5 dB due to the
interchangeability of the sensors.
Measurements are made in a wide field in order to obtain a flat wave, the characteristic
impedance of the ambient field must be equal to 377 ohms.
0.1 V/m to 200 V/m
0.1 V/m
0.5 dB
250 µs
400 ms
100 ms
0.2 dB
Tolerances
20°C ± 2°K
65% ± 5%
9 V ± 0.5 V
150 MHz ± 1%
10 V/m ± 1%
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