CCS120
Operation
Hauser
13
5
Operation
5.1
Sensor design
a0006354
Fig. 7: Sensor design
5.2
Measuring principle
The amperometric sensor is based on the conversion of the measuring variable chlorine in
electrical current. Two electrodes covered by an electrolyte are in contact to the medium via a
membrane. It has a platinum working electrode and a silver halogenide coated counter or
reference electrode. The chlorine compounds contained in the medium 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
to the chlorine concentration within the sensor’s operating range and only slightly pH dependant
for this type of sensor. The primary signal is converted by the amplifier electronics of the sensor
into a 0 ... 5 µA output signal which is displayed by the transmitter.
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4
1
Membrane cap
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Thread NPT 3/4"
2
Sensor shaft
4
TOP68 plug
