OHAUS STARTER 300, Инструкция по эксплуатации

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3.1.3 Performing 2-point calibration
• Step 1: Perform the first calibration as described above in "
Performing 1-point calibration ".
• Step 2: Rinse the electrode with pure water.
• Step 3: Place the electrode in the next calibration buffer and press
Cal
The calibration icon and the measurement icon appear on the display. The measurement
icon is blinking during calibration measurement. The meter endpoints according to the preselected
endpoint mode after the signal has stabilized or after pressing
Read .
When the calibration point is finished, the relevant buffer value is displayed and stored; the
measurement icon blinks 3 times and disappears. Then, the endpoint stability and auto endpoint
icons
blink 3 times and freeze on the display and
“
Cal 2
” or “
Cal 3
” stops blinking. If the
calibration was endpointed manually, then only endpoint stability icon blinks 3 times and
freezes on the display.
To finish the calibration and return to the sample measurement, press
Read . The offset value and
the slope are then shown on the display for 3 seconds. To reject the calibration, press Exit before
the meter returns automatically after 3 seconds to the measurement screen.
Note:
The use of a temperature sensor or an electrode with a built-in temperature sensor 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
4.2 )
To ensure the most accurate pH measurement, you should perform a calibration once a day.
3.2 Sample measurement
3.2.1 pH measurement
Place the electrode in the sample and press Read to start the measurement. The measurement
icon appears on the display. The measurement icon is blinking during measurement and the
display shows the pH value of the sample. The automatic endpoint
is the default setting of
the meter. When the signal has stabilized, the sample reading freezes, the measurement icon
blinks 3 times and disappears. Then, the endpoint stability and auto endpoint icons
blink 3
times and freeze on the display.
By pressing and holding
Read , you can switch between the auto and manual endpoint modes. To
manually endpoint a measurement, press Read : the sample reading freezes, the measurement
icon blinks 3 times and disappears. Then, the endpoint stability icon blinks 3 times and
freezes on the display.
Stability criterion for pH and mV measurement
– The signal of the sensor input may not
change by more than 0.1mV in 6 seconds.
3.2.2 mV measurement
To switch to mV mode, press Mode .
To perform a mV measurement, follow the same procedure as for pH measurement.
3.3 Temperature measurement
For better accuracy, we recommend the use of either a built-in or a separate temperature probe. If