Hanna HI 5221, Инструкция по эксплуатации

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pH Resolution
Select the desired pH resolution with this option. Choose from
one (X.X), two (X.XX) or three (X.XXX) digits displayed past the
decimals.
To set the pH Resolution:
• Press while in pH Measure mode.
• Press .
• Use or to select the pH Resolution option.
• Press and use or to highlight the
desired option.
• Press to confirm your selection or press to cancel operation.
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• To return to normal
Measure
mode press .
Note : If the reading is out of range, “ ---- ” will be displayed on the LCD.
Outside Cal Range warns the user if the current reading is out
of the calibrated area. The calibrated area is that part of the pH
range in which the calibration point ensures an accurate reading.
If the reading is taken out of the calibration area, the “
Outside
Cal Range ” message will start blinking on the LCD. The
calibrated area is calculated in accordance with the pH resolution
used during the measurement. To avoid triggering this message,
the buffer values have to be well-distributed in the desired
measurement range.
If measurements are taken successively in different samples, it is
recommended to rinse the electrode thoroughly with deionized
water or tap water and then with some of the next sample before
immersing it into the next sample solution.
The pH reading is affected by temperature. In order to measure the pH accurately, the temperature effect
must be compensated. To use the
Automatic Temperature Compensation (ATC) feature, connect and
place the HI 7662-W temperature probe into the sample as close as possible to the electrode and wait for
a few seconds.
If the temperature of the sample is known,
Manual Temperature Compensation (MTC) can be used by
disconnecting the temperature probe.
Notes : • For single channel pH measurements ( HI 5221 ), “ MTC ” or “ ATC ” indicators will be displayed on
the LCD, while for dual channel pH measurements ( HI 5222 ) “ MTC1 ”/” MTC2 ” or “ ATC1 ”/” ATC2 ”
indicators will be displayed (Channel dependent).
• For mV/Rel mV measurements, “ NoProbe ” or “ TEMP ” indicators will be displayed on the LCD
( HI 5221 only), respectively, “ NoProbe 1 ”/“ NoProbe 2 ” or “ TEMP1 ”/” TEMP2 ” indicators
( HI 5222 only) for mV/Rel mV/ISE measurements, depending on the temperature probe status and
channel selected.
• When in MTC mode, the temperature can be modified by pressing for
pH Measure
mode and
for mV / Rel mV Measure mode ( HI 5221 only) if the Reading Mode option is Direct
( HI 5222 only). The temperature value can be adjusted with or from -20.0 °C to
120.0 °C. Press to save the new temperature value or press to return to Measure
mode.
• When in ATC mode for pH, or TEMP for mV/Rel mV, “ ---- ” will be displayed on the LCD if the
measured temperature is under or over temperature range (-20.0 °C to 120.0 °C).