Calibrate - ProMinent DULCOTEST BCR Serie Instrucciones De Montaje Y De Servicio

Put the sensor into operation
6.1

Calibrate

CAUTION!
– Following the replacement of a
membrane cap or electrolyte, you
must carry out a gradient calibra‐
tion
– The slope has to be re-calibrated
at regular intervals to ensure per‐
fect operation of the sensor. The
calibration intervals are 1 - 4
weeks, depending on the quality
of the water
– Avoid air bubbles in the sample
water. These could result in incor‐
rect metering. Air bubbles that
adhere to the membrane of the
sensor may result in too low a
reading and thus in over-
metering.
– Please note the applicable
national guidelines for calibration
intervals
Prerequisites
Constant flow rate at the in-line
–
probe housing
Constant temperature of the
–
sample water
Equal temperature of sample
–
water and sensor (wait approx.
15 minutes)
The sensor has been run-in
–
Constant pH value
–
50
Zero point calibration
If the sensor is operated with a ProMinent
control device, then zero point calibration
is not generally necessary. Perform a zero
point calibration if you are working in the
measuring range 0.01 ... 0.5 mg/l or
working in other measuring ranges at the
lower end of the measuring range (< 10
%).
1. Dip the sensor in a bucket of clean
water without disinfectant or oxidant
(e.g. common still mineral water)
2. Stir with the sensor until the meas‐
ured value at the control device is
stable for 5 mins
3. Calibrate the control device to zero
in accordance with its operating
manual
4. Re-install the sensor into the in-line
probe housing (e.g. DGMA; DLG III)
Gradient calibration
1. Immediately determine the disinfec‐
tant content of the sample water
using a suitable measuring kit (e.g.
DPD)
2. Set the value ascertained on the
control device according to its oper‐
ating instructions
ð Repeat the calibration after one
day to ensure that the sensor
has reached its maximum sen‐
sitivity (gradient).