Endress+Hauser Topclean S CPC30, Руководство по эксплуатации

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Topclean S 7 Maintenance
Hauser 121
7.1.2 Inspecting the sensor
Check for air bubbles in the pH electrode:
Air bubbles indicate incorrect installation. Therefore check the installation position:
• Permitted: 15° to 165° to the horizontal.
• Horizontal installation or upside-down installation are not permitted (except when using an
ISFET pH sensor).
Check for reference system reduction:
The inner metal lead of the reference system (Ag/AgCl) of a combination electrode or a separate
reference electrode is usually light-brown and matt. A silver-coloured reference system is reduced
and therefore defective. The cause is a current flowing through the reference element.
Possible causes for the current flow:
• Incorrect operating mode of the measuring instrument (PML pin connected, but operating mode
without solution ground ("without PML") selected. See functional description, field "Select
connection type" on p. 56.
• Shunt in measuring cable (e. g. through humidity) between reference line and grounded screen
or PM line.
• Measuring instrument defective (shunt in reference input or entire input amplifier downstream
of PE).
Removing diaphragm blockages:
Blocked reference system diaphragms can be mechanically cleaned (only sensors with ceramic
diaphragms, does not apply to teflon diaphragms or open ring electrodes):
• Use a small key file.
• Only file in one direction.
7.1.3 Maintenance of digital sensors
To maintain digital sensors with Memosens technology, proceed as follows:
1. If an error occurs or the sensor must be replaced according to the maintenance schedule, take
a new or pre-calibrated sensor from the laboratory. In the laboratory, sensors are calibrated
under optimum ambient conditions which guarantees a higher calibration quality.
2. Remove the soiled sensor and install the new sensor.
3. The sensor-specific data are automatically transmitted to the transmitter. A release code is not
required.
4. Measurement continues.
5. Take the used sensor back to the laboratory. There, you can regenerate it for reuse without
measuring point down time.
– Clean the sensor. Use the cleaning agents indicated above.
– Inspect the sensor for damages.
– If the sensor is not permanently damaged, calibrate it for reuse.
7.2 Manual calibration
When you perform a calibration, consider the operating mode of the pH input. With preselection
"with solution ground" (= connection with PML), the PM lines of the CPM153 must also be
immersed in the calibration solution.
!
Note!
The assembly must be moved into the service position with the service switch, before calibrating.