wtw Oxi 197i, Руководство по эксплуатации

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What to do if... Oxi 197i
50
Error message
E7 E7 E7 E7
AR flashes
continuously
Measured value too low
Measured value too
high
Display
to
to to
to
Sensor symbol flashes
Cause Remedy
Membrane damaged
– Membrane damaged – Regenerate sensor
– Membrane head not screwed
on tight enough
– Screw membrane head tight
Cause Remedy
No stable measured value
– Membrane contaminated – Clean membrane
Cause Remedy
– Insufficient
flow
– Provide flow to the sensor
Cause Remedy
– High amount of dissolved
substances
– Correct solubility function
using the salinity equivalent
– Air bubbles bump on the
membrane with high velocity
– Avoid direct flow to the
membrane
– The carbon dioxide pressure is
too high (> 1 bar)
– Measuring not possible
Cause Remedy
– Time-out of the interface – Check the instrument
connected
Cause Remedy
– Calibration interval expired – Recalibrate the measuring
system