Idiomas disponibles
Idiomas disponibles
7
Instructions for troubleshooting and fault remedy
User qualification: instructed user, see
Fault
Sensor cannot be cali‐
brated and measured value
greater than DPD measure‐
ment
Sensor cannot be cali‐
brated and sensor meas‐
ured value less than DPD
measurement
Instructions for troubleshooting and fault remedy
Ä Chapter 1.3 'Users' qualifications' on page 38
Possible cause
The calibration was carried
out with DPD 1 in the pres‐
ence of organic bromina‐
tion agents such as
BCDMH and a low free bro‐
mine fraction.
Run in period too short
Membrane cap damaged
Troublesome substances in
the water
Short circuit in the meas‐
uring line
Distance between mem‐
brane/electrode is too great
DPD chemicals out of date
pH value < pH 6
Run in period too short
Sample water flow rate too
low
Air bubbles on the outside
of the membrane
Interfering substances in
the sample water (surfac‐
tants, oils, alcohols, corro‐
sion-inhibitors)
Remedy
Calibrate the sensor using
DPD 4
Observe the run in period
Replace membrane cap
Check water for trouble‐
some substances and
remedy this
Identify short circuit and
eliminate the cause
Screw the membrane cap
up to its stop
Use new DPD chemicals,
repeat calibration
Increase pH value (pH 6 ...
9.5)
Observe the run in period
Correct flow rate
Increase the flow within the
permitted range
Contact ProMinent
51
Capítulos
Solución de problemas
