
30
The pH-meter is to be calibrated at buffer solution temperature of (20±5) °C.
In this case temperatures of the two calibration solutions shall not differ by more
than 0.5
С.
Prior to calibration the reference electrode or combined electrode filling hole
is to be opened.
2.3.3.2 pH-meter calibration procedure
Calibration is undertaken against one of the two buffer solutions exhibiting
1.65 and 9.18 pH values at solution temperature of (25.0 ± 0.2)
С.
1
Clean electrode (electrodes) and temperature sensor in distilled water,
first, (in two vessels in succession) and then in the first buffer solution
against which calibration is to be undertaken which exhibits pH = 1.65 at
solution temperature of (25.0 ± 0.2) °С.
2
Power up the pH-meter. Press the
key. The display shown in
Fig. 2.1 shall come up.
Fig. 2.1
3
Place pH-electrode (electrodes) and temperature sensor in the first fresh
buffer solution. Press the
key. The first buffer solution shall be
identified. The display shown in Fig. 2.2 shall come up.
Fig. 2.2
CAL
◄
RECORD
ENTER
CALIBRATION No 1
6.02 pH
PUT THE PROBE IN
1
st
BUFFER SOLUTION
AND PRESS
ENTER
CALIBRATION No 1
− . − − −
рН
23.1
С
А