Sample Measurements; Temperature Compensation - Mettler Toledo SevenGo Duo pro SG68 Instrucciones De Manejo

4 Press End to accept the calibration and return to sample measurement.
The calibration result is shown on the display.
5 Press Exit to reject the calibration.
Performing a two-point calibration
The second point of a DO calibration is done with a zero oxygen solution.
1 Follow steps a - c for the first calibration point as described above.
2 Rinse the sensor with deionized water.
3 Place the electrode in the zero oxygen solution and press CAL.
Cal 2 appears on the display.
The meter endpoints according to the preselected endpoint mode, automatically after the signal has
stabilized or after pressing READ. The relevant buffer/standard value is shown on the display.
4 Press End to accept the calibration and return to sample measurement.
The calibration result is shown on the display.
5 Press Exit to reject the calibration.
Note
Zero-point calibrations are frequently a source of error. Due to the very low zero current of METTLER TOLEDO
sensors, a zero-point calibration is unnecessary even for measurement at low oxygen concentrations.

4.9 Sample measurements

Place the sensor in the sample and press READ to start a measurement.
The display shows the readings of the sample in either the single channel or dual channel mode.
Note: to switch between the single and dual channel measurement screen, press and hold MODE for 3
seconds.
The endpoint format blinks, indicating a measurement is in progress.
As soon as the measurement is stable according to the selected stability criterion, the Stability icon
appears.
Note
If the "automatic endpoint" format is selected, the measurement stops automatically as soon as the
Stability icon appears.
If the "manual endpoint" format is selected, press READ to manually stop the measurement.
If the "timed endpoint" format is selected, the measurement stops after the preset time.

4.10 Temperature compensation

We recommend the use of either a built-in or a separate temperature probe. If a temperature probe is used, ATC
and the sample temperature are displayed. If no temperature sensor is used, MTC is displayed and the sample
temperature should be entered manually. The meter accepts only an NTC 30 kΩ (pH) and an NTC 22 kΩ (DO)
temperature sensor.
The meter calculates the temperature-adjusted electrode slope using this temperature and shows the
temperature-compensated pH/ion value in the measurement display.
SevenGo Duo pro™ Operating the pH/ORP/Ion/DO meter SG68​ ​ 15