Xylem handylab pH 11 - Manual (Page 16)

Operation handylab pH 11
16 ba75366e04 01/2011
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:
Note
Incorrect calibration of pH electrodes leads to incorrect measured values.
Calibrate regularly before measuring.
Temperature
sensor
You can measure with or without a temperature sensor. If a temperature sen-
sor is connected, it is indicated on the display by TP.
Note
The measuring instrument automatically recognizes the type of the tempera-
ture sensor used. Therefore, you can connect temperature sensors of the
NTC30 or Pt1000 type.
The temperature measurement is absolutely essential for a reproducible pH
measurement. If the measurement is made without a temperature sensor,
proceed as follows:
1 Connect the electrode to the measuring instrument.
2 Adjust the temperature of the buffer solutions or test solutions,
or measure the current temperature, if you measure without a
temperature sensor.
3 In conjunction with the electrode, check or calibrate the mea-
suring instument. How to calibrate is described in section 4.3.
4 Select the measuring mode with .
1 Measure the current temperature of the test sample using a
thermometer.
2 Enter the temperature on the instrument: Set the temperature
value of the test sample using <
▲ > <▼>.