inoLab pH/ION 735
What to do if...
77
6
What to do if...
6.1
pH and ORP measurement
Error message,
OFL
or UFL
(measuring range
exceeded or undercut)
Error message,
Error
(calibration error)
Cause
Remedy
Electrode:
– Air bubble in front of the
diaphragm
– Remove air bubble
– Air in the diaphragm
– Extract air or
moisten diaphragm
– Gel electrolyte dried out
– Replace electrode
Test sample
– The pH value lies outside the
measuring range
– not possible
Cause
Remedy
Electrode:
– Diaphragm contaminated
– Clean diaphragm
– Membrane contaminated
– Clean membrane
– Moisture in the plug
– Dry plug
– Not enough electrolyte
– Top up electrolyte
– Electrode obsolete
– Replace electrode
– Electrode broken
– Replace electrode
– Socket damp
– Dry socket
Calibration procedure:
– Incorrect solution temperature
(without temperature sensor)
– Set up correct temperature
– Incorrect buffer solutions
– Select buffer solutions
suitable for the calibration
procedure
– Buffer solutions too old
– Use only once.
Note the shelf life
