OAK Environmental Express PH250, Instruction Manual

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Error messages and trouble shooting
39
● Trouble shooting
T
his section describes causes and actions to take for problems that customers frequently ask.
The indicated value fluctuates
< Problem with the electrode >
<
Problem with the instrument
>
< Problem with the sample >
Cause How to solve problem
The electrode is dirty. Clean the electrode.
The electrode is broken. Replace the electrode.
The level of reference electrolyte gel. Replace the electrode.
Cause How to solve problem
There is a motor or other device
causing electrical interference.
Measure at a place where no influence from
induction is given. Ground all AC-powered
equipment.
The electrode is not connected
correctly.
Connect the electrode properly.
Cause How to solve problem
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 stability of electrode is affected
by the sample solution.
It is important to select an electrode that is
appropriate for the sample. Consult your dealer. To
confirm an electrode that is appropriate for the
sample, check the pH electrode selection guide in
our catalogue, or refer to our website.