Troubleshooting
8
Fault
Possible cause
The sensor
Run-in period too short
cannot be
Diaphragm cap damaged
calibrated -
meter/
Interference from water
controller
contaminant (see section 15
display value is
"Technical Data", cross-sensitivity)
greater than
DPD-1
Short circuit in signal cable
measurement
DPD chemicals spent
The sensor
Run-in period too short
cannot be
Diaphragm cap deposits
calibrated -
meter/
controller
Sample water flow inadequate
display value is
smaller than
Air bubbles on the outside of the
DPD-1
measurement
diaphragm
Reference electrode spent (shiny
patches showing)
Surfactant in water (diaphragm is
translucent)
No electrolyte in diaphragm cap
Electrolyte is penetrating sample
water via gas bubbles
Interference from water
Measuring
value readout
contaminant (see section 15
is "Zero"
"Technical Data", cross-sensitivity)
ClO
measuring range limit
Sensor incorrectly connected to
controller
Measuring
Air bubbles on the outside of the
value readout
diaphragm
unstable
Diaphragm damaged
Cause lies with the controller
26
Troubleshooting
content below the lower
2
Remedy
See section 7.1 "Run-in Period"
Replace diaphragm cap. Run-in
sensor, calibrate
Identify interfering contaminant and
implement remedy
Identify short circuit and repair
Use new DPD chemicals, repeat
calibration
See section 7.1 "Run-in Period"
Remove deposits (see section 9
"Maintenance"). Replace diaphragm
cap. Run-in sensor, calibrate
Increase sample water flow (see
section 15 "Technical Data")
Tap to remove air bubbles and
increase flow if necessary
Return sensor to ProMinent
Remove surfactant and replace
diaphragm cap. Run-in sensor,
calibrate; use CDP sensor
Add new electrolyte (see sections 5
"Assembly", 7.1 "Run-in Period"
and 7.2 "Calibration")
Discuss with ProMinent
Identify interfering contaminant and
if necessary replace water
Add ClO
and then repeat
2
calibration or use appropriate
sensor
Connect sensor correctly to
controller
Tap to remove air bubbles and
increase flow if neccessary
Replace diaphragm cap. Run-in
sensor, calibrate
Identify cause and remedy
ProMinent
®