Thermo Fisher Scientific CyberScan PD 300 - Manual (Page 14)

Instruction Manual PD 300
4.3 pH calibration
Before starting calibration, make sure you are in pH measurement mode.
NOTE
We recommend calibration with at least two calibration standards that bracket (one
above and one below) the expected sample range. One point calibration is possible as
long as the chosen buffer is close to the expected sample value.
When you re-calibrate your meter, old calibration points are replaced on a “point-by-point”
basis. For example:
• if you previously calibrated your meter at pH 4.01, 7.00, and 10.01, and you re-
calibrate at pH 7.00, the meter retains the old calibration data at pH 4.01 and pH
10.01.
Preparing for pH calibration
This meter is capable of up to 5-point pH calibration to ensure accuracy across the entire pH
range of the meter. Select from the following buffer options:
• pH 1.68, 4.01, 7.00, 10.01 and 12.45.
The meter automatically recognises and calibrates to these standard buffer values, which
makes pH calibration faster and easier.
Be sure to remove the protective electrode storage bottle or rubber cap of the electrode
before calibration or measurement. If the electrode has been stored dry, hydrate the
electrode in electrode storage solution or tap water for 10 minutes before calibrating or taking
readings to saturate the pH electrode surface and minimise drift.
Rinse your electrode in deionised water after use, and store in electrode storage solution. If
storage solution is not available, use fresh pH 4.01 or 7.00 buffer solution for short term
storage.
Do not reuse buffer solutions after calibration. Contaminants in the solution can affect the
calibration and eventually the accuracy of the measurements. See Accessories for information
on pH buffer solutions.
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