Help Texts - ProMinent DULCOMETER diaLog DACb Assembly And Operating Instruction

[Diagnostics]
18.5

Help texts

Content of the help
texts
The DPD value is too
small, DPD value >
MRS + 2 %
The slope is too
shallow, < 20 % of the
MR
The slope is too steep,
> 300 % of the MR
The zero point is too
low, < 3.2 mA
The zero point is too
high, > 5 mA
An unknown calibration
error
In the residual period
parameter set 1 is used
174
Cause
If the calculated reference value (e.g.
DPD1) for calibrating a sensor is less
than 2 % of the measuring range, then
calibration is not possible.
The sensor can no longer detect the
chemicals to be measured
The sensor has been permanently
affected by for example surface-active
substances (surfactants).
The sensor delivers a measured signal
that is less than 3.2 mA. This value is
outside of the specification.
You would like to calibrate the zero
point but the sensor is still detecting the
chemical to be measured
If parameter set 2 is not active, then
parameter set 1 is activated
Remedy
Increase the concentration of
the chemical to be measured
in the process/sample water
and determine the reference
value again (e.g. DPD1) after
the run-in period.
Replace the membrane cap
and replace the electrolyte for
new material
Make sure that none of these
substances are present in the
water. Replace the membrane
cap and replace the electro‐
lyte for new material
Check the raw value in mA in
the Information menu, by
pressing in the main dis‐
play. If the value is < 3.2 mA,
then this is not the correct
sensor signal. Check the
cabling and replace the
sensor with a new sensor.
Rinse the sensor with water
containing no chemicals that
are to be measured before
zero point calibration. The
water with which the zero
point is determined should
also not contain traces of this
chemical. Use mineral water
without carbon dioxide for this
purpose.
Check the control signals/lines
that switch the parameter set
or check the timer settings.