horiba LAQUAact-PD110, Instruction Manual

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Troubleshooting
92
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The measured value is out of the measurement range
When the measured value is below the display range, "Ur" appears. When the measured
value is over the display range, "Or" appears.
• How to check for instrument defect
Short the metal part of the outer tube to the center pin of the electrode
connector of the corresponding channel of the instrument. If "Ur" or
"Or" appears in this condition, consult your dealer.
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Repeatability of the measured value is poor
Cause How to solve problem
Sample is out of the
measurement range.
Use a sample within the measurement range.
Electrode is not immersed
enough to cover liquid junction.
The electrode must be immersed up to the liquid junction.
As a guide, immerse to at least 3 cm from the tip of the
electrode.
The electrode cable is broken. Replace the electrode.
Calibration is not performed or
performed incorrectly.
Perform calibration correctly.
Instrument defect Check as explained below.
Cause How to solve problem
Effect of the sample solution
Repeatability becomes poor when the pH of the sample
changes over time.
The electrode is dirty.
Clean the electrode. (Electrode cleaning solution 220 or
250 is recommended.)
The electrode is cracked. Replace the electrode.
The internal solution of the
electrode runs out or
contaminated.
Replace the internal solution with new one.
The level of internal solution in
reference electrode is low. Replenish the internal solution of the reference electrode
until it is higher than the level of the sample.