Endress+Hauser Topcal S CPC310, Руководство по эксплуатации

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Commissioning
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7 Commissioning
7.1 Points to note when commissioning digital sensors
pH sensors with Memosens technology save the calibration data. Consequently, the procedure for
commissioning these sensors differs to that for standard electrodes.
Proceed as follows:
1. Install the transmitter and the assembly.
2. Connect the transmitter and the sensor cable.
3. Configure the transmitter for your specific requirements (see "System configuration" section).
4. Connect the sensor, precalibrated at the factory, with Memosens technology and immerse it
into the medium or the buffer.
5. The sensor-specific calibration data saved are automatically transmitted to the transmitter.
6. The measured value is displayed.
Normally, you can accept this value without calibrating the sensor.
Calibration is only necessary in the following instances:
– Where there are strict requirements in terms of accuracy
– When the sensor has been in storage for more than 3 months
7. Check the transmission of the measured value to the process control system or to the switching
unit.
7.2 Points to note when commissioning ISFET sensors
Switch-on behavior
A closed control loop is created once the measuring system is switched on. The measured value
adjusts to the real value during this time (approx. 5 ... 8 minutes). This settling occurs every time
the liquid film between the pH-sensitive semiconductor and the reference lead is interrupted (e.g.
from dry storage or intensive cleaning with compressed air). The settling time in question depends
on how long the interruption lasts.
Sensitivity to light
Like all other semiconductor components, the ISFET chip is sensitive to light (fluctuations in
measured value). However, this only affects the measured value when light falls directly on the
sensor. Therefore, avoid direct sunlight during calibration. Normal ambient light does not affect
measurement.
7.3 Function check
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Warning!
• Make sure there is no danger to the measuring point. Uncontrolled actuated pumps, valves or
similar could lead to damage to instruments.
• Make sure that all the connections have been established correctly.
• Make sure the supply voltage matches the voltage indicated on the nameplate!