ProMinent FLE 010 SE Notice D'utilisation page 6

Trouble shooting
Error description
Unstable measuring
signal
The display reading
does not react to
different calibration
solutions
Slope too low/high
Drifting sensor signal
Maintenance
ATTENTION
The sensor must be inspected regularly!
Observe current local guidelines!
Check whether the sensor is damaged or the LaF
Cleaning
ATTENTION
If organic solvents are used to clean the sensor, the polymeric shaft material and the
adhesive of the LaF
Wipe contamination carefully away with help of a lint-free paper towel and rinse thoroughly. Remove any
remaining contamination by polishing the LaF
paste (order no. 559810). Remove the residual polishing paste by carefully rinsing with lukewarm water.
Immerse the sensor over night in tap water with 1 ppm fluoride and calibrate again.
Shutting down
Rinse the sensor after operation with distilled/de-ionized water and dry it carefully by means of a soft fuzz-
free paper towel. Dab the LaF
Waste disposal
ATTENTION
Observe current local guidelines!
Technical Data
Measurable variable:
Application:
Measuring range:
With measuring transducer:
pH range:
1 ppm F - value:
Slope:
Response time T (up):
95
Min. conductivity of tap water:
Operating pressure max.:
Flow:
Working temperature range:
Storage temperature range:
Humidity:
Cause of error
Measuring transducer loose
Defective reference electrode
Wet connection between measuring
transducer and sensor
Ground circuit
Air bubbles below the LaF
Contaminated LaF crystal
3
Sensor is not connected
Defective sensor
Defective cable
Defective measuring transducer
Sensor leaking
Contaminated LaF
3
Wrong calibration solution
Exceeding the allowed pH range
Interfering ingredients
(cf. "Cross-sensitivity" in "Technical
Data")
Defective reference electrode
Leaking sensor
Crystal can be demaged!
3
crystal with help of a soft lint-free paper towel and polishing
3
crystal only cautiously (cf. "Transport and storage"). -
3
fluoride ion activity
tap water
0.05 ppm...saturation (= 2.63x10
0.05...10 ppm (= 2.63x10
5.5...8.5
105 ... 130 mV
56...60 mV/dec at 25 °C
< 30 s (for concentrations > 0.5 ppm)
> 100 µS/cm
7 bar (no pressure bursts)
recommended 20 L/h (10 ... 200 L/h)
1...35 °C
1...50 °C
max. 90 % relative humidity, not dewy
Remedy
Screw the measuring transducer
firmly onto the sensor
Change the reference electrode
Dry the connection
Change the wiring
crystal Depressurize the DLG, twist
3
the sensor
A Prevent bubble formation,
if necessary increase flow
Cleaning of the LaF
(cf. Cleaning)
Connect the sensor
Change the sensor
Change the cable
Change the measuring transducer
Change the sensor
crystal Cleaning of the LaF
(cf. Cleaning)
Use correct calibration solution
Adjust pH of the measuring water
to pH 5 – 9
Avoid interfering substances
Change the reference electrode
Change the sensor
crystal is contaminated or covered with gas bubbles!
3
-6
mol/L ... 5.26x10
crystal
3
crystal
3
-6 mol/L ... saturation)
-4
mol/L)