OHAUS STARTER 2100, Инструкция по эксплуатации

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3.1.2 Performing 1-point calibration
Calibration: pH electrode need to be calibrated with pH standard buffer solution before a proper
pH measurement. Calibration is to display the right pH value when meter receive the mV value
signal from the pH electrode.
Slope: the linear coefficient between mV and pH according to theoretical value (e.g. -
59.16mV/pH @ 25°C which means 100% slope);
Offset: the mV value when pH value is 7.00. (Theoretical value is 0 mV);
When
STARTER 2100
is in pH measurement mode (see 3.2), we can do the pH electrode
calibration; place the pH electrode in a calibration buffer:

Press button- Cal ,
“
Cal
1
” displays on the top right of the screen and is blinking. Measurement
icon appear on the top of the screen, is blinking during calibration.

If the reading is stable, press button- Read to lock the reading and finish 1 point calibration.
The buffer value (e.g. pH 7.00) with the temperature display on the screen, the meter can
recognize the buffer automatically (auto buffer recognition).
The 1-point calibration is finished; now we have 3 choices to do next:

Press button- Read to store the 1-point calibration data and exit, the offset and the slope are
shown on the display for 3 seconds then return to the measurement screen.

Press button- Exit to reject the calibration, return to the measurement screen.

Press button- Cal to do the 2-point calibration.
Note: With the 1-point calibration only the offset is adjusted. If the pH electrode was previously
calibrated with multi-point calibration the previously stored slope will remain. Otherwise
theoretical 100% slope (-59.16 mV / pH @25
°
C) will be used.
3.1.3 Performing 2-point calibration

Perform 1-point calibration as described above.

Rinse the pH electrode with pure water and wipe off water with tissue.

Place the electrode in the next calibration buffer and press button- Cal ,
“
Cal
2
” displays on the
left bottom of the screen and
“
Cal
” is blinking.
and appear on the top of the screen,
is blinking during calibration.

When reading is stable, press button- Read to lock the reading and finish 2-point calibration,
disappear. The buffer pH value (e.g. 7.00 pH ) with the temperature display on the screen.
The 2-point calibration is finished, and then we have 2 choices to do next:

Press button- Read to store the 2-point calibration, the offset and slope are shown on the
display for 3 seconds then return to the measurement screen.

Press button- Exit to reject the calibration, return to the measurement screen.
Note: The use of a temperature electrode (e.g. STTEMP30) or a pH electrode with a built-in
temperature sensor (3-in-1 pH electrode) is recommended. If you use the MTC mode, you should
enter the correct temperature value and keep all buffer and sample solutions at the set
temperature. (See 4.1)