Horiba Scientific LAQUAact D-72G, Инструкция по эксплуатации

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mV, ORP measurement
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Performing measurement
You can perform measurement in the measurement mode by immersing the electrode in
the sample. Also, you can use the automatic hold function to perform stability judgment
of the measured value.
1. Wash the 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
electrode.
If calibration is performed with the port closed, the
internal solution does not flow and the
measurement value is not stabilized. Make sure to
keep the port open during calibration.
3. Immerse at least 3 cm from the tip of the
electrode in the sample solution.
In order to flow the internal solution into the
sample solution, immerse the liquid junction in the
sample solution surely.
4. While the electrode is immersed in the sample solution, press the key.
Stabilization judgment starts and the HOLD icon blinks. When the value is stabilized,
the HOLD icon changes from the blinking state to the lit state and the display is fixed
to the measured value at the stable time. Press the
key again to release fixing the
measured value.
Note
・
The criteria of stability judgment in the automatic hold measurement are as follows.
Potential variation for 10 seconds is less than 1 mV and temperature variation is less than
2.0°C
・
Note that when measuring the ORP of a sample solution that has extremely low
concentrations of oxidants and reductants (such as tap water, well water, or water treated
with purifying equipment), there may be less responsiveness and repeatability in general.
・ If alkaline water is left, its ORP value changes considerably. Always measure alkaline Ion
water promptly.
key
Stabilized