What to do if...
inoLab pH/ION 735
78
No stable measured
value
Obviously incorrect
measured values
Sensor symbol flashes
Cause
Remedy
pH electrode:
– Diaphragm contaminated
– Clean diaphragm
– Membrane contaminated
– Clean membrane
Test sample
– pH value not stable
– Measure with air excluded if
necessary
– Temperature not stable
– Adjust temperature if
necessary
Ele test sample:
– Conductivity too low
– Use suitable electrode
– Temperature too high
– Use suitable electrode
– Organic liquids
– Use suitable electrode
Cause
Remedy
pH electrode:
– Not connected
– Connect electrode
– Cable broken
– Replace electrode
– pH electrode unsuitable
– Use suitable electrode
– Temperature difference
between buffer and test
sample too high
– Adjust temperature of buffer
or sample solutions
– Measurement procedure not
suitable
– Follow special procedure
Cause
Remedy
– Calibration interval expired
– Recalibrate the measuring
system
