Hanna Instruments HI6221 - Page 59

59
CALiBrATiON
Repeat with up to 5 buffers.
A small c icon on display (
C
), next to the custom value, indicates calibration with custom
buffers.
pH Calibration Procedure using Automatic Calibration
With the electrode and temperature sensor connected to the meter:
1. Select the correct buffer group or buffer value for calibration.
2. Select Manual Temperature source if calibration is done without a temperature sensor.
3. Remove the plastic protective cap from the probe and rinse the electrode with purified water.
4. Fill a rinse beaker 2/3 full with the first buffer solution.
5. Swirl the electrode and temperature sensor in the buffer solution.
6. Raise and lower the probe several times. Discard the solution.
7. Fill the calibration beaker 2/3 full with the first buffer solution.
8. Slowly place the electrode and temperature sensor in the selected buffer. Dislodge bubbles that
may adhere to the sensors.
For most applications it is recommended to start with pH 7.01 buffer (or pH 6.86).
Use calibration buffers that bracket the samples pH.
For acidic samples it is recommended to use pH 4.01, 3.00, and/or 1.68 buffers.
For alkaline samples it is recommended to use pH 9.18, 10.01 and/or 12.45 buffers.
9. Tap Clear Calibration to start a fresh calibration and clear all previously used buffers.
If using a new pH electrode it is recommended to tap Clear Calibration to clear all buffers and
start new.
10. Rinse the electrode and temperature sensor in the buffer, place in the rinse beaker then
calibration beaker.
A
Buffer has been recognized. Waiting for reading to stabilize.
B
Check the buffer value and use fresh buffer if:
• The buffer cannot be recognized.