CCS240/241
Maintenance
Hauser
27
9.2.5
Regenerating the sensor
During measurement, the electrolyte in the sensor is gradually exhausted due to chemical
reactions. The gray-brown silver chloride layer that is applied to the anode at the factory
continues to grow during sensor operation. However, this has no effect on the reaction taking
place at the cathode.
A change in the color of the silver chloride layer indicates an effect on the reaction that is
taking place. Carry out a visual inspection to ensure that the gray-brown color of the anode
has not changed. If the color of the anode has changed, e.g. if it is spotted, white or silvery,
the sensor must be regenerated.
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Send the sensor to the manufacturer for regeneration.
9.2.6
Reconditioning the sensor
Longterm operation of the sensor (> 3 months) in a chlorine-free medium, i.e. with very low
sensor currents, may lead to deactivation of the sensor. This deactivation is a continuous
process that results in a lower slope and longer response times. After long-term operation in a
chlorine-free medium, the sensor can be reconditioned.
The following materials are required for reconditioning:
• Deminieralized water
• Beaker
• Pour approx. 100 ml (3.38 fl.oz) aqueous chlorine dioxide solution
