Ozone concentration in water: Sensors

Appropriate sensor is fundamental to any measurement setup. Variety of different types and variants are available, depending on the measured quantities, sensor dimensions, as well as usage workflow, environment, and installation method. The vast majority of sensors listed below are just components of a larger measurement setup, and can therefore be satisfactorily used only with a compatible analyzer. Sensors for in-technology measurements should be installed inside our probes, ensuring their fixing and protection, and these connect to a terminal block. Variants for laboratory and portable usage are terminated with the appropriate connector. Sensors generally have the shortest lifetime of the entire setup, due to direct contact with the measured medium.

Ozone sensor CSZT43


The CSZT43 is amperometric membrane-based sensor designed to measure ozone concentration (and also temperature) in water, primarily for the purpose of continuous technology control.

The sensor is based on a pair of electrodes immersed in an electrolyte, separated from the measured environment by a membrane permeable to ozone (but also to other gases, such as O2, Cl2). Ozone is reduced at the cathode, resulting in the generation of an electric current proportional to the partial pressure of ozone. The sensor consume ozone, which is taken from the measured environment, and thus all factors influencing the rate of diffusion to the cathode surface take effect. The output current also depends on temperature, which INSA analyzers compensate based on readings from the sensor's built-in thermometer.

TypeSuitable forDimensions
CSZT43PS-RInstallation with SPO41, SPO41K, SPO42, SPO41MEK, PB42V, PB43V, PE G3/4KØ14.5 x 57 mm
CSZT43PL-RInstallation with SPR42, SPR41ME, PE G3/4L, SVK42Ø14.5 x 113 mm
PrincipleAmperometric membrane-based sensor
Measurement range0.01 - 5.0 mg/l
Operating temperature1 - 40 °C
Zero signal fluctuationtyp. ±0.01 mg/l
Flow of the samplemin. 20 cm/s
Materials in contact with mediumPolyethylene terephthalate, PTFE, silicone, stainless steel