wtw pH 1970i, Руководство по эксплуатации

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Operation pH 1970i
16 ba75690e01 01/2007
4.2 Measuring
4.2.1 General information
You can measure the following variables:
z
pH value
z
ORP voltage
Preparatory activities Perform the following preparatory activities when you want to measure:
Warning
When connecting an earthed PC/printer, measurements cannot be per-
formed in earthed media as incorrect values would result. The RS232
interface is not galvanically isolated.
Note
Incorrect calibration of pH electrodes leads to incorrect measured val-
ues. Calibrate regularly before measuring.
Measuring the
temperature
For reproducible pH measurements, it is essential to measure the tem-
perature of the test sample.
You have the following possibilities of measuring the temperature:
z
The temperature sensor integrated in the electrode measures the
temperature automatically (example: TetraCon 325).
z
Automatic temperature measurement by the external temperature
sensor (accessory) NTC30 or Pt1000. This method is required
when using electrodes without integrated temperature sensor. Con-
nection of the temperature sensor, see section 1.3 S
OCKET FIELD
.
z
Manual measurement and input of the temperature.
1 Connect the pH sensor (pH depth armature or pH electrode) to
the measuring instrument (see section 1.3 S
OCKET FIELD
).
2 Adjust the temperature of the buffer solutions or test solutions,
or measure the current temperature, if you measure without a
temperature sensor.
3 Calibrate or check the measuring instrument with the pH sen-
sor. How to calibrate is described in section 4.3.
4 Select the measuring mode with <M> .