Design And Function - ProMinent DULCOTEST CTE 1-mA Mode D'emploi

The chlorine concentration can be optimally controlled in conjunction with
the DULCOMETER
ProMinent metering pumps. Typical applications include the disinfection of
potable, industrial, process and cooling water with chlorine-based disinfec-
tants, particularly in the presence of higher pH values up to 9.5.
The CTE sensor (total chlorine) is used in swimming pools in combination
with the CLE sensor (free chlorine) in order to monitor bound chlorine
(chloramines).
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Sensor design The CTE total chlorine sensor comprises 3 main parts, the top section, the
electrode shaft and the membrane cap (see fig. 1). The membrane cap filled
with electrolyte forms the measurement compartment into which the
electrodes are immersed.
A micro-porous membrane separates the measuring compartment from the
sample medium.
The amplifier electronics are embedded in plastic in the upper part of the
electrode shaft.
The sensor has a passive 4-20 mA two-wire interface. The sensor's power
supply is located in an external controller, e.g. DULCOMETER
Measured
variables Total chlorine: free chlorine (Cl
Function of
sensor The CTE total chlorine sensor is a membrane-capped amperometric two-
electrode sensor. It has a platinum working electrode and a silver halogenide-
coated counter- or reference electrode. The chlorine compounds contained in
the sample water diffuse through the membrane. The constant polarisation
voltage between the two electrodes instigates the electrochemical reaction of
the chlorine compounds on the working electrode. The resulting current is
measured as a primary signal (amperometric measurement principle). It is
proportional within the operating range pf the sensor to the chlorine concen-
tration and this type of sensor is only slightly pH-dependant. The primary
signal is converted by the amplifier electronics of the sensor into a
4-20 mA temperature-corrected output signal which is displayed in the
DULCOMETER
®
ProMinent
®
D1C, chlorine measurement and control device and

Design and function

bound chlorine (chloramines)
organic bound chlorine (e.g. cyanuric acid derivates)
®
D1C, chlorine.
Application / Design and function
(dissolved) HOCl, OCl - )
2
® D1C, chlorine.
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