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6.8.3. — Electrode slope out of range (< 85% or >105%)
When or shows up:
1)
Make sure there is no damage on the electrode’s glass bulb (if so, an electrode replacement is
necessary). Check if there is air bubble inside the glass bulb. If so, shake the electrode with force
for several seconds to remove the bubble.
2)
Check the quality of buffer solution. Make sure it’s fresh and clean and conforms to the meter’s
buffer series setting.
3)
Set the meter to factory default setting mode (refer to section 6.6.7), then recalibrate it.
If the meter is still not working after the above checkings, it’s time to replace a new pH electrode or contact
6.9
Notes about pH
1)
Never store pH electrode in pure water as it will damage the electrode. Always store the electrode
in 3M KCL soaking solution (AI1107).
2)
If you find any air bubble in the glass bulb of the pH sensor, simply shake the probe with force for
a few times to remove it. The existence of an air bubble in the glass bulb will significantly decrease
the stableness of measurement.
3)
pH electrode is technically a chemical battery. Every pH electrode will eventually die even if you
don’t use it at all. The typical service life of a pH electrode is 1-2 years depending on how you
use and maintain it. We recommend replacing your pH electrode after one year of use to ensure
the best result.
4)
Always keep the meter’s connector clean and dry, otherwise it may lead to an inaccurate
measurement. If contaminated, clean the connector with alcohol prep pads and blow-dry.
7
ORP Measurement:
7.1
Sample Test:
5.1.1. Press to power on, connect the ORP combination 301 Pt-S electrode (See Section 5 for
connection tutorial), the meter will enter ORP measurement mode automatically.
5.1.2. Screw off the storage bottle. Rinse the electrode with pure water. Shake off excess water or blot-
dry with clean tissue or kimwipe. Stir the electrode for a few seconds after it’s dipped into the sample
solution and then hold it still. Wait for the reading to get fully stabilized ( appears and stays). Then
save the measurement by pressing