wtw pHotoFlex, Operating Manual

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Operation pHotoFlex / pHotoFlex Turb
56 ba75491e05 04/2009
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 meter
determines the following values and calculates the calibration line as
follows:
Note
You can display the slope in the unit, mV/pH or % (see section 4.6.4).
AutoRead The calibration procedure automatically activates the AutoRead func-
tion.
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.
Displaying and down-
loading calibration data
to interface
You can view the data of the last calibration on the display. Subse-
quently, you can download the displayed calibration data to the inter-
face, e. g. to a printer or PC, with the <PRT> key.
The calibration record of the last calibration can be found under the
Configuration / pH & ORP / Calibration / Calibration record menu item.
Determined val-
ues Displayed calibration data
1-point Asy
z
Asymmetry = Asy
z
Slope = Nernst slope
(-59.16 mV/pH at 25 °C)
2-point Asy
Slp.
z
Asymmetry = Asy
z
Slope = Slp.
3-point Asy
Slp.
z
Asymmetry = Asy
z
Slope = Slp.
The calibration line is calculated
by linear regression.