wtw Multi 350i, Operating Manual

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Multi 350i Operation
31
Calibration points Calibration can be performed using one, two or three buffer solutions in
any order (single-point, two-point or three-point calibration). The mea-
suring instrument determines the following values and calculates the
calibration line as follows:
Note
You can display the slope in the units, mV/pH or % (see section 4.3.3).
AutoRead In calibration, the AutoRead function is automatically activated.
The current AutoRead measurement can be terminated at any time
(accepting the current value).
Calibration record When finishing a calibration, the new calibration values are displayed
as an informative message (
i
symbol) first. Then you can decide
whether you want to take over these values of the new calibration or
whether you want to continue measuring with the old calibration data.
After accepting the new calibration values the calibration record is dis-
played.
Determined
values Displayed calibration data
1-point ASY
!
Asymmetry = ASY
!
Slope = Nernst slope
(-59.16 mV/pH at 25 °C)
2-point ASY
SLO
!
Asymmetry = ASY
!
Slope = SLO
3-point ASY
SLO
!
Asymmetry = ASY
!
Slope = SLO
The calibration line is calculated
by linear regression.