11
Preparing the Meter for pH Calibration
Before starting pH calibration, make sure you are in the correct measurement mode.
When you switch on the meter, the meter starts up in the units last used. For
example, if you shut the meter off in "pH" units, the meter will read "pH" units
when you switch the meter on.
Do not reuse pH calibration solutions after calibration. Contaminants in the solution
can affect the calibration, and eventually the accuracy of the measurements. u
Be sure to remove the protective rubber cap from the pH electrode before
calibration or measurement.
If the electrode has been stored dry, wet the probe in
tap water for 10 minutes before calibrating or taking readings to saturate the pH
electrode surface and minimize drift.
Wash your probe in deionized water after use, and store in electrode storage
solution. If storage solution is not available, use pH 4.0 or 7.0 buffer.
The pH/DO 300 meter is capable of up to 5-point pH calibration at pH 1.68, 4.01, 7.00,
10.01, and 12.45 to ensure accuracy across the entire pH range of the meter . The meter
automatically recognizes and calibrates to these standard buffer values, which makes
pH calibration faster and easier.
To calibrate at 5 points you must select a 5-pt calibration in SETUP mode program P3.2
on page 36. You can select 2, 3, 4 or 5 calibration points for pH calibration.
4.2