Sartorius PT-10 Mode D'emploi page 15

[Standardize]
8. If "Error" is displayed next to the slope symbol, your
electrode is not functioning properly.
The slope must be between 90 and 105%. The portable
meter does not accept or store values displayed with
the "Error" indicator. Press [Enter] to continue.
If no ATC probe is connected during calibration, the
meter uses the nominal buffer values at 25°C.
If an ATC probe is connected, the meter adjusts contin-
ually for temperature. In this case, the pH value of the
buffer at the current temperature is taken into account
when calculating the slope of the electrode.
9. Enter a third standard:
Immerse the electrode in the third buffer solution, stir,
allow to stabilize, and press [Standardize]. Refer to
steps 7 and 8 before continuing.
10.After each buffer is entered, the "Standardizing"
symbol switches off and the "Measuring" or "Stability"
symbol is displayed, indicating that the meter has
returned to the normal measuring mode.
Standardize your meter and electrode using at least two
buffers, with pH values bracketing the expected pH of
your samples.
Note: Stirring shortens the electrode response time.
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