Endress+Hauser Memosens COL37E, Руководство по эксплуатации

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Commissioning Memosens COL37E
10 Hauser
Refer to Operating Instructions BA02002C on the product page ( www.endress.com/cml18 )
for the measurement, calibration and adjustment of the sensor on the Liquiline Mobile
CML18.
Recommended procedure after replacing a spot cap
First calibrate and adjust the sensor at the zero point and then in the presence of oxygen.
5.1.1 Zero point calibration
The zero point is not so important when working with relatively high concentrations of
oxygen. In these types of application, a zero point calibration is required only after the spot
cap has been replaced.
However, once oxygen sensors are used at low concentrations and in the trace range, they
must also be calibrated at the zero point.
Zero point calibrations are demanding as the ambient medium - usually air - already has a
high oxygen content. This oxygen must be excluded for zero point calibration of the sensor.
A calibration with the COY8 zero-point gel can be used for this purpose:
The COY8 oxygen-depleting gel creates an oxygen-free medium for zero point calibration.
Prior to sensor zero point calibration, check the following:
• Is the sensor signal stable?
• Has the adjustment time of 30 min - 40 min for the COY8 zero-point gel elapsed?
• Is the value displayed plausible?
1. If the sensor signal is stable:
Calibrate the zero point.
2. If necessary:
Adjust the sensor by accepting the calibration data.
If the oxygen sensor is calibrated too early, this can result in an incorrect zero point.
Rule of thumb: operate the sensor for at least 30 min in the zero-point gel.
Follow the instructions in the kit documentation enclosed with the COY8 zero-point gel.
5.1.2 Calibration in air with 100% rH
1. Remove the sensor from the medium.
2. Clean the outside of the sensor carefully with a damp cloth.
3. Suspend the sensor just above the surface of the water. Use the calibration bottle
provided for this purpose.
Do not immerse the sensor.
4. Allow a temperature compensation time of approx. 20 minutes for the sensor in the
ambient air. Make sure that the sensor is not exposed to any direct ambient effects
(direct sunlight, drafts) during this time.