YEO-KAL 615, Руководство пользователя, Страница: 33 / 48

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To make a solution with 100% saturation, aerate a sample of fresh water for about two
hours. A fish tank air pump and bubbler is ideal for this purpose. When you have the
calibration standards ready, perform the following steps:
1. Before calibrating dissolved oxygen, ensure that the temperature sensor is
reading accurately and, if necessary, perform the temperature calibration
described above. If you have replaced the membrane on the dissolved oxygen
sensor, you must wait for 2 hours after replacing the sensor membrane `before
the calibration can be performed. You should also check that the stirrer is
operating correctly. The paddle should oscillate freely when the instrument is
performing measurements.
2. Select DISSOLVED OXYGEN by pressing the calibration key, use the arrow keys
and select calibrate Inst. Press ENTER and use ARROW keys to select D.O. %
Press ENTER and use arrow keys to select high or low set points Press
ESC
to exit
without changing the instruments calibration.
3. If you wish to continue, immerse the probe in the 0% oxygen solution, a visual
display of the raw data for zero can be seen on LCD display. When the data is
stable press
ENTER , the dissolved oxygen calibration coefficients will then be
automatically updated. You will be asked if you wish to calibrate high set point
ENTER
or
ESC
4. Select Cal high set point and press ENTER Immerse the probe in the aerated
solution, a visual display of the raw data is seen on the LCD display. When the
data is stable press
ENTER , the dissolved oxygen calibration coefficients will
then be automatically updated and the instrument will return to the calibration
menu.
pH Calibration
The pH sensor is calibrated using buffer solutions with a pH of 3 – 9.0 and 6-12. If the
probe is fitted with a refillable ph sensor, it is good practice to refill prior to calibration
(see
pH/ORP Sensor Maintenance) . To calibrate the pH sensor, proceed as follows:
1. Select pH from the calibration key, the message CAL High or Low set point will
appear (ENTER/ESC) will be displayed. Press
ESC to exit without changing the
instruments calibration.
2. If you wish to continue, Select low set point and immerse the probe in a solution
of the desired pH between 3 and 9, Press
ENTER and the raw data will appear
press ENTER when stable press ENTER and then use the numbered keys to enter
the value of the standard used press
ENTER, the pH calibration coefficients will
then be automatically updated.
3. Rinse the probe in distilled water to remove all traces of the low buffer solution.
Immerse the probe in a buffer solution with pH between 6.0 and 12.0, Select Cal