3 General principles
3.2 Diagnostic values
PIOX R721
2021-09-01, UMPIOX_F72xV1-3EN
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3.2
Diagnostic values
Amplitude
The amplitude (unit: %) is the ratio of max. values of the signals to the product of LED lightness and exposure time of the
image sensor. At delivery, the amplification with water is normalized to 100 %.
Amplification (gain)
The amplification (unit: dB) is the ratio of max. values of the signals to the product of LED lightness and exposure time of
the image sensor. At delivery, the amplification with water is normalized to 20 dB. 0.01 % of the amplification corresponds
to a image amplification of 100 dB.
Symmetry
Symmetry is the relation of amplitudes of both slit images. At delivery, they are optically adjusted to the same value.
Quality
The quality (unit: %) is an evaluation of the signal shape in comparison to the ideal one.
SNR
The SNR (unit: dB) is the ratio of useful signal and noise signal. A high SNR is ideal.
Combination of diagnostic values
It is possible to realize a combined evaluation of diagnostic values to determine the cause of error in situations with strong
light scattering:
• A contaminated measurement optics and a turbid fluid can lead to a very low amplitude (e.g., < 0.1 %) or to a very high
amplification (> 80 dB).
• A contaminated measurement optics and optical maladjustment lead to a symmetry >>1 or <<1.
• A contaminated measurement optics decreases the quality more than a turbid fluid.
• A turbid fluid decreases the SNR more than a strongly absorbing fluid.
3.3
Sensor values
Sensor humidity
The relative humidity within the sensor electronics is measured with an integrated humidity sensor. The humidity sensor
only measures water vapor but does not measures other vapors. The sensor humidity must not exceed 80 %.
Sensor temperature
The temperature within the sensor electronics is measured with an integrated temperature sensor.
