VWR MD 8000 L, Руководство по эксплуатации

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MD 8000 L What to do if...
ba77218e01 11/2018
85
No stable measured
value
Obviously incorrect
measured values
15.2 Dissolved oxygen
Error message
OFL, UFL
The measured value is outside the measuring range.
Cause Remedy
IDP pH sensor:
– Junction contaminated – Clean junction
– Membrane contaminated – Clean membrane
– pH sensor soiled – Clean the pH sensor
Test sample:
– pH value not stable – Measure with air excluded if neces-
sary
– Temperature not stable – Adjust temperature if necessary
IDP pH test sample:
– Conductivity too low – Use a suitable IDP pH sensor
– Temperature too high – Use a suitable IDP pH sensor
– Organic liquids – Use a suitable IDP pH sensor
Cause Remedy
IDP pH sensor:
– Sensor unsuitable – Use a suitable IDP sensor
– Temperature difference
between buffer and test sample
too great
– Adjust temperature of buffer or sam-
ple solutions
– Measurement procedure not
suitable
– Follow special procedure
More information and instructions on cleaning and exchange of
sensors are given in the documentation of your sensor.