56
CALiBrATiON
11.1. pH CALIBRATION
Calibration Guidelines
• Set up a routine service schedule where measurement integrity is validated.
• Do not handle the sensing surfaces of the sensors.
• Avoid rough handling and abrasive environments that can scratch the reactive surfaces of the
sensors.
• For best technique, use a rinse beaker and a separate calibration beaker for each buffer.
Discard buffers after use.
• Do not return the used buffers to the bottles of “fresh” buffer.
• For measurements across a temperature gradient (when water temperature is drastically different
from the buffers), allow the electrodes to reach thermal equilibrium before conducting calibrations
or making measurements.
• During calibration the temperature probe should be in the calibration buffer.
pH Calibration Type
There are three options available with buffer selection from 8 predefined standards and 5 user-defined
custom values:
Automatic
• Instrument automatically selects from Buffers in Use group.
Semiautomatic
• Instrument automatically selects from all available standard and custom buffers.
The user can manually select between buffers that are close in value when the angle bracket turns blue.
Manual
• Manual buffer input from all available standard and custom values.
Automatic Calibration
With this option selected, the HI6221 automatically selects the closest buffer to the pH value being
measured from all active buffers selected as Buffers in Use.
Selecting Buffers in Use, Standard or Custom (navigation guidelines)
To move buffers from the Available Standard Buffers or Available Custom Buffers trays to the Buffers
in Use trays:
1. From Measurement screen, tap Measurement Menu icon ( ).
2. Select pH Reading Parameter, and tap Calibration tab next.
To Next Page
Loading...
