Endress+Hauser OUSAF44, Руководство по эксплуатации

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OUSAF44 Commissioning
Hauser 21
2. While the D-tryptophan is dissolving, add deionized water until the beaker contains an
approximate volume of 450 ml.
3. Continue stirring at 30 °C (86 °F) until the tryptophan is completely dissolved.
4. Dilute the solution to 1000 ml in a volumetric flask.
 You now have a parent solution of D-tryptophan with a concentration of 1000 mg/l
(ppm).
5. Create a series of calibration solutions from the parent solution by diluting, and
determine the absorbance of the solutions at the sensor wavelength using a laboratory
spectrometer.
 Use these value pairs (concentration and absorbance values) in the transmitter for
the data sets for application calibration.
Instead of potassium dichromate or D-tryptophan you can also use your process medium
for calibrating/adjusting and for application calibration. Here, also produce a series of
dilutions of known concentration and determine the absorbance in the laboratory.
7.2.2 Easycal
Easycal enables you to perform a calibration/an adjustment which is traceable to NIST
without any liquid standards.
Detector with Easycal: function
1 2
3 4
A0033709
 9 Filter in "out" position
1 NIST-traceable filter (high)
2 Locking screw
A0033708
 10 Filter in "in" position
3 Positioning pin
4 Lens assembly
Every Easycal device has two traceable filters - one filter with a nominal 0.5 AU and another
filter with 1 AU (absorbance unit) - which are placed individually or together in the device
measuring path. These filter(s) are scanned with traceable testing equipment and the actual
absorbance at individual wavelengths is determined.