ProMinent DULCOTEST CGE 2-4P-10 ppm, Operating Instructions Manual, Page: 28 / 68

Pr o Minent
® 28
Fault
Sensor cannot
be calibrated –
readings from
measuring
device/
controller
higher than
DPD-1
calibration
Sensor cannot
be calibrated –
readings from
measuring
device/
controller
lower than
DPD-1
calibration
Reading is
”zero”
Reading is
unstable
Action
왘
See chapter 7.1 ”Run-in period”
왘
Replace membrane cap, break in
sensor, calibrate
왘
Examine water for contaminants
and take action
왘
Trace short circuit and eliminate it
왘
Use new DPD chemicals, repeat
calibration
왘
Increase pH value to 5.5-9.5
왘
See chapter 7.1 ”Run-in period”
왘
Remove coating (see chapter 9
”Maintenance”), replace membrane
cap, run in sensor, calibrate
왘
Correct flow (see chapter 15
”Technical data”)
왘
Remove bubbles by tapping and
increase flow if necessary
왘
Eliminate surfactants and replace
membrane cap, break in sensor and
calibrate, use CDP sensor if
necessary
왘
Reduce pH to 5.5-9.5
왘
Pour in fresh electrolyte (see ch. 5
”Assembly”, ch. 7.1 ”Run-in period”
and ch. 7.2 ”Calibration”)
왘
Consult ProMinent
왘
Add chlorine and repeat calibration,
use a suitable sensor
왘
Connect sensor correctly
왘
Run for at least 3 h before calibration
왘
Replace sensor
왘
Remove bubbles by tapping and
increase flow if necessary
왘
Replace membrane cap, break in
sensor, calibrate
왘
Repair the fault
Possible Cause
Run-in period too short
Membrane cap damaged
Contaminants in the water (see
”cross sensitivity” in chapter 15
”Technical data”)
Short circuit in the leads
DPD chemicals too old
pH value < 5.5
Run-in period too short
Coating on membrane cap
Flow of water sample too low
Air bubbles on outer part of
membrane
Surfactants in the water
(membrane is transparent)
pH value > 9.5
No electrolyte in membrane cap
Electrolyte forced into water sample
by gas bubbles
Chlorine content below lower
measuring range limit
Sensor connected to controller
incorrectly
Run-in period too short
Sensor defective
Air bubbles on outer part of
membrane
Membrane damaged
Fault with controller
8 Troubleshooting
Troubleshooting
BA_DT_085_09_07_4spr.p65 13.09.2007, 14:18 Uhr 28