Standard Addition With Blank Value Correction (Bw Add) - wtw inoLab Level 3 Operating Manual

7.4.7 Standard addition with blank value correction
(Bw Add)
In the "Standard addition with blank value correction"
procedure, a known amount of standard solution is added to
the sample in two steps.
The ion concentration in the linear range of the electrode
characteristic curve is increased with the first addition.
The second addition is equivalent to the standard addition.
The ion concentration in the sample is calculated from the
change in potential.
1 Select the measuring method (see section 7.4.1).
2 Prepare two standard calibration solutions.
3 Perform a two-point calibration according to the user
guidance.
4 As soon as a stable value for the second standard
calibration solution is reached, the
display indicator
the electrode is displayed after the two-point
calibration. The probe symbol shows the electrode
evaluation after the two-point calibration.
h
stops flashing. The slope (mV) of
Ion concentration
131