Table of Contents
Advertisement
● Performing calibration
Calibration is necessary to measure pH accurately.
We recommend performing calibration once a day, before the first measurement.
According to the following procedure, perform calibration accurately.
Note
・ Perform two-point calibration using pH 7 and pH 4 when you know that the sample is
acidic; pH 7 and pH 10 when you know that the sample is alkaline.
・Perform three-point calibration using pH 4, pH 7, and pH 10 when the sample is unknown.
・ You can confirm the current calibration data in the setting mode and delete the calibration
data in the setting mode. (Refer to "Displaying the latest calibration and inspection data"
(page 70), "Deleting calibration data" (page 75).)
• pH standard solution setting is USA or NIST
This section describes the procedure for two-point calibration of USA standard, pH 4 and
7, as an example of general calibration.
1. Clean the pH electrode with pure water (or
deionized water) and wipe it with filter paper
or tissue paper.
2. Open the internal solution filler port of the pH
electrode.
If calibration is performed with the port closed,
the internal solution does not flow and the
measurement value is not stable. Make sure to
keep the port open during calibration.
3. Perform the 1st point calibration. Immerse at
least 3 cm from the tip of the pH electrode in
the pH 7 standard solution.
In order for the internal solution to flow into the
standard solution, make sure to immerse the
liquid junction in the standard solution surely.
4. Press the
mode.
Stability judgment automatically starts and the pH icon blinks until the measured
value stabilizes. When the measured value stabilizes, the pH icon changes from the
blinking state to the lit state.
Tip
The standard solution type for the calibration is shown on the upper right screen.
key to enter the calibration
pH measurement
27
Advertisement
Table of Contents
