Pr
o
Minent
®
Page 30
Free Chlorine
Zero Point Calibration
If a ProMinent controller is being used to operate the sensor, zero point calibration is not usually
necessary. Zero point calibration should be carried out, however, if operating the sensor at the
lower measurement threshold or when using the 0.5 ppm variant.
Immerse the sensor in a container of clean, chlorine-free tap water.
Stir with the sensor until the measured variable displayed at the controller has remained stable
for 5 min.
Calibrate the controller to zero in accordance with the operating instructions.
Reinstall the sensor in the in-line probe housing (DGM; DLG) as described in ”Installation”.
Slope
Test
Determine the chlorine content in the sample water using an appropriate measurement system
(e.g. DPD 1).
Set the resulting value at the controller in accordance with the operating instructions.
Repeat calibration after 1 day!
Possible
values
Initial value
Increment
Lower value
Upper value
Remarks
Measured value 0.01 ppm
0 ppm
100 ppm
Error message
Condition
Remarks
Calibration Cl not possible!
Cl slope too low
Calibrate again
Sensor slope too low
(<25 % of norm slope)
Calibration Cl not possible!
Cl slope too high
Calibrate again
Sensor slope too high
(>300 % of norm slope)
DPD value too low!
DPD <2 % of measuring
Calibrate again after adding
DPD > x.xx ppm
range
chorine
Calibration of the Chlorine Sensor
During the calibration, the D1C sets the controller outputs to “0”. Exception: If a base load or
manual controller output was set, these are maintained during the calibration. The standard signal
outputs mA (measured value or correction value) are frozen. The measured value registered during
the start of the calibration is proposed as the DPD value; this value is adjustable (arrow keys!).
Calibration is only possible if the DPD value is
≥
2 % of the measuring range. On successful
completion of calibration, all error checks which refer to the measured value are restarted.
IMPORTANT
The measuring range of the chlorine sensor must correspond to the adjusted measuring
range (factory setting: 0–2 ppm). A change of the measuring range must be done before
calibration!
D1C2-Cl-011-GB
Permanent display 1
Permanent display 2
only with control
(w = setpoint)
ppm
0.45
mea. val.
fd. fwd.:
reg. val.:
0.45 ppm
w:
1.00 ppm
70 %
59 %
Positive values of control variable: Chlorine
Negative values of control variable: Dechlorine
(chlorine
destruction)
D1C2-Cl-012-GB
calibration Cl
calibration Cl
DPD-value:
0.45 ppm
zero p.:
slope:
4.00 mA
6.50 mA/ppm
calibration Cl
zero p.:
slope:
4.00 mA
6.75 mA/ppm
Permanent display 1
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24.02.2009 11:56:04 Uhr
