Troubleshooting - ProMinent DULCOTEST CDR 1-mA-2 ppm Betriebsanleitung

Troubleshooting

7 Troubleshooting
User qualification: instructed user, see
Fault
Sensor cannot be cali‐
brated – display on
measuring device/
controller greater than
DPD-1 measurement.
Sensor cannot be cali‐
brated – display on
measuring device/
controller lower than
DPD-1 measurement.
Measured value display
is 0.
54
Ä Chapter 1.2 „Users' qualifications" on page 41
Possible cause
Run in period too short.
Diaphragm cap damaged.
Troublesome substances in
the water.
Short circuit in the measuring
line.
DPD chemicals out of date.
Run in period too short.
Deposits on the diaphragm
cap.
Sample water flow rate too
low.
Reference electrode worn out
(showing shiny points).
Air bubbles on the outside of
the diaphragm.
No electrolyte in diaphragm
cap.
Electrolyte pushed out by gas
bubbles in the sample water.
Troublesome substances in
the water.
Remedy
See "Run in period".
Replace diaphragm cap, allow sensor
to run in, calibrate it.
Check water for troublesome sub‐
stances and remedy this.
Identify short circuit and eliminate the
cause.
Use new DPD chemicals, repeat cali‐
bration.
See "Run in period".
Remove the deposits - see "Mainte‐
nance"; replace diaphragm cap; allow
sensor to run in, calibrate it.
Correct flow rate.
Return sensor.
Remove air bubbles by tapping them
and increase flow rate if necessary.
Fill with new electrolyte.
Contact ProMinent.
Check water for troublesome sub‐
stances and remedy this.