horiba LAQUAact-PD110, Instruction Manual

Page: 37 / 117

pH measurement
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pH measurement
You can measure the pH of the sample with a pH electrode.
Use a combination electrode incorporating a glass electrode and a reference electrode
for measurement. A single glass electrode cannot be used with this instrument.
pH can be measured using channel 1 of the instrument.
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Setting the instrument
• Setting temperature compensation (default: ATC)
Automatic temperature compensation function can be used by using a combination
electrode equipped with a temperature sensor or connecting a temperature
compensation electrode. By measuring temperature during calibration of the pH
standard solution and compensating for the change in pH value of the standard solution
due to its temperature changes, you can perform calibration using the value matched to
the standard solution temperature (only when the standard solution setting is NIST and
USA). However, the function does not convert the pH value according to the temperature
characteristics of each sample, and you must record the obtained value together with the
sample temperature value. The variation of pH value accompanying the temperature
change differs depending on the sample.
If you do not use the automatic temperature compensation function, match the
temperature setting of the instrument to the temperature of the standard solution during
calibration and match the sample temperature to the temperature setting of the
instrument in measurement. By doing so, you can obtain the correct measurement value
without being affected by sensitivity variation caused by temperature.
1. Press the key to enter the setting mode.
2. Press the keys to select "TEMP" (temperature setting) and then press the
key.
If the temperature connector (T) is connected, "ATC" (automatic temperature
compensation) appears. If the temperature connector (T) is not connected, "MTC"
(manual temperature compensation) appears.