Troubleshooting - ProMinent DULCOTEST CGE 2-mA-10 ppm Operating Instructions Manual

Troubleshooting

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