horiba LAQUAact-DO110, Инструкция по эксплуатации

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Dissolved oxygen measurement
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Performing calibration
Calibration of the DO electrode is required to measure dissolved oxygen accurately.
We recommend performing calibration once a day, before the first measurement.
According to the following procedure, perform calibration accurately.
You can use the saturated oxygen concentration mode (%) or dissolved oxygen
measurement mode (mg/L) for calibration.
Note
To perform accurate calibration, set the air pressure value before calibration ("Setting air
pressure correction (default: 101.3 kPa)" (page 22)).
• Calibrating in the saturated oxygen concentration mode (%)
Note
・
Air calibration must be performed in clean air. If air calibration is performed in a location
subject to dramatic temperature change, exposed to wind and rain, or near a heating
appliance, an error may occur or the value may not be stabilized.
・
Do not hold the DO electrode with hand during calibration. DO electrode may be affected
by temperature, causing an unstable value.
1. Clean the membrane at the tip of the DO
electrode with pure water (or deionized water)
and wipe it with a soft cloth at least 10
minutes before calibration.
Be careful not to break the membrane at the tip
of the electrode.
2. Press the key to enter the saturated
oxygen concentration mode.
3. Hold the DO electrode still in clean air.
4. Press the key to enter the calibration mode.
Stability judgment starts and the sat.ratio icon blinks. When the value is stabilized,
the sat.ratio icon changes from the blinking state to the lit state. When you press the
key or the key, the calibrated value is displayed (the calibrated value differs
depending on the conditions because it is affected by temperature and air pressure).