pHotoFlex
®
pH
Operation
19
ba75977e03
10/2017
Obviously incorrect
measured values
pH value / ORP voltage
Measuring range
exceeded or undercut
Measured value display
----
(calibration error)
Cause
Remedy
– Measurement disturbed by
external light
– Close the external light cover.
– Cell not correctly inserted
– Insert the cell so that it is
positioned on the bottom of
the cell shaft.
– Cell contaminated
– Clean the cell
– Cell shaft contaminated
– Clean the cell shaft
– Dilution set incorrectly
– Set the dilution
– Selected program unsuitable
– Select other program
– Zero measurement incorrect
– Perform zero measurement
– Blank value incorrect
– Remeasure the blank value
Cause
Remedy
Electrode:
– Air bubble in front of the
junction
– Remove air bubble
– Air in the junction
– Extract air or
moisten junction
– Gel electrolyte dried out
– Replace electrode
Test sample:
– The pH value lies outside the
measuring range
– not possible
Cause
Remedy
Electrode:
– Junction contaminated
– Clean junction
– Membrane contaminated
– Clean membrane
– Moisture in the plug
– Dry plug
