wtw pH/Cond 3320 - Page 78

What to do if... pH/Cond 3320
78 ba77054e03 03/2018
No stable measured
value
Obviously incorrect
measured values
Cause Remedy
Electrode:
– Junction contaminated – Clean the junction
– Membrane contaminated – Clean membrane
Test sample:
– pH value not stable – Measure with air excluded if
necessary
– Temperature not stable – Temper if necessary
Electrode + test sample:
– Conductivity too low – Use a suitable electrode
– Temperature too high – Use a suitable electrode
– Organic liquids – Use a suitable electrode
Cause Remedy
Electrode:
– Electrode unsuitable – Use a suitable electrode
– Temperature difference between
buffer and test sample too great
– Adjust temperature of buffer or
sample solutions
– Measurement procedure not suit-
able
– Follow special procedure