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5 point calibration, recommended for accurate pH measurements spanning > 6 pH.
Examples:
Measurements expected to take place between pH 3 and pH 11 would require a full 5 point with pH
2, pH 4, pH 7, pH 10 and pH 12 buffers to achieve the most accurate measurements.
A number of experiments conducted sequentially that each have a relatively narrow range of
expected values, but whose values overall are spread over a wide range, for which pH will be taken
without interim calibrations between the experiments will require a 5 point calibration
Experiment 1 values are expected between pH 2 and pH 3
Experiment 2 values are expected between pH 7 and pH 9
Experiment 3 values are expected between pH 9 and pH 12
5.2 Before calibration
To ensure the best possible calibration results, always observe the following guidelines:
Only use the buffer set with which your meter is configured
Only use fresh buffers for a calibration
Make sure your buffer sets are at the same temperature range as your sample to be measured
Before, during and after calibration, always clean and flush your probe. Please see the probe
manual for instructions on how to clean the probe.
Make use of the calibration reminder function to ensure calibrations are made at appropriate
time intervals (see chapter 5.5)
Make use of Sentron twin-neck calibration fluid bottles as they minimize contamination of the
buffer and allow convenient storage and calibration using a single bottle.
When a new probe is attached to a meter, or when a probe has not been used for a while, the probe
may react slow or has low slope readings after calibration. In this case the probe will need to be
“soaked” (revitalized). This will reactivate an inactive probe and ensures it will produces stable
readings.
For more information on revitalization and treatment of the probe, please review the probe
manual.
