Swann AMI Oxytrace, Руководство оператора

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AMI Oxytrace QED
Product Description
A-96.250.531 / 300617
9
Faraday
Verification
For AMI Oxytrace QED only.
When a direct current is passed through water by means of two
electrodes, electrolysis of the liquid takes place, according to the
laws of Michael Faraday. Water is converted to molecular oxygen
and hydrogen.
Thus, by controlling the current, a fixed, known amount of oxygen,
which is independent of temperature and pressure, may be gener-
ated. If the sample flow is known, an exact oxygen concentration
increment can be generated at low levels. This increment is used to
verify the flawless operation of the whole system. Thereby the re-
sponse characteristics (incremental change and response time) of
the sensor are taken into account. Sensor failures (loss of electro-
lyte etc.) can be detected very easily as shown in the plot below.
Unusual sensor performance is recognized immediately and gives
also a maintenance indication to the operator/user. The faraday
verification is therefore an excellent QA/QC tool.
0
5
10
15
20
25
30
30
Time [Sec]
defective sensor
operational sensor
Dissolved Oxygen [ppm]
60 90 120 150 180 210 240 270 300 330
35
40