LAQUA LAQUA-PC200 Series, Instruction Manual

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Error messages and trouble shooting
70
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 (pH mode)
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.
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.
The electrode is cracked. Replace the electrode.
The internal solution of the
electrode is partially depleted or
contaminated.
Replace the electrode.