dissolved ozone sensor

Dissolved O3 Sensor

  • Fast response (<4.5 seconds), dissolved O3 microsensor
  • Direct measurements of dissolved O3 for waste water monitoring and scientific research
  • Extremely stable signal for accurate and reliable measurements
  • Portable meter or online, continuous monitoring options

The amperometric O3 micro-sensor has been developed for the in-situ determination of ozone containing aqueous solutions.

Therefore the sensor is suitable for direct measurements in coloured, turbid and solid containing solutions. Compared with all the other commercially available ozone sensors this amperometric ozone micro-sensor contains a redox catalyst and works with a very low analyte consumption, that streaming of the sensor membrane or stirring of the analyte is not necessary. And, an additional stirrer is not necessary for stationary measurements.

The second advantage of the micro-sensor compared to other ozone sensors is the very fast response time of the AMT ozone micro-sensor with T90% below 4.5 seconds compared with a minimum of approximately 80 to 120 seconds in the case of the conventional sensors.

The third advantage of the new microsensor is based on the micro-sensor technology itself. The signal stability of amperometric ozone micro-sensors is essential better. And the high local signal resolution allows some new applications, as for instance the profiling in μm-steps. Besides, measurements in soft sediments or muds became also practicable.


related products


laboratory and portable sensor

Dissolved Ozone Sensor

This sensor has been developed for laboratory and simple field use and must be used in combination with the MS08 Handheld Portable Meter.

The sensor consists of a titanium housing, a waterproof connection with the cable (IP 68), an exchangeable sensor head and a removable protection cage (on your own risk – no guarantee in the case of mechanical destruction).

This sensor could be equipped both with the ozone sensor head and with a galvanic oxygen sensor head.

Other concentration ranges can be delivered on request. The exchange of the sensor head is very easy by pull off and push on.


shallow water sensor for continuous monitoring

Online Dissolved O3 Sensor

The shallow water sensor has been developed for use in combination with so called CTD-probe systems up to depths of 100 meters and for applications with up to 10 bar pressure.

Every shallow water sensor is equipped with a special underwater connector, type wet con BH-4-MP.

Further characteristics are the integrated electronic device, the titanium housing and the exchangeable sensor head. This sensor could be equipped both with the ozone sensor head and with a galvanic oxygen sensor head. Other concentration ranges can be delivered on request. The exchange of the sensor head is very easy by pull off and push on.


the working principle of the O3 microsensor

Because of the partial pressure of gaseous ozone dissolved in the sample, the analyte is separated by permeation through the membrane. The membrane is only pervious for gases, so that liquids, ions and solids are not able to reach the inner electrolyte of the sensor.

The sensor contains inside an electrolyte with a redox catalyst (= redox mediator) and 3 electrodes. The electrode materials have been choosen and prepared very carefully to realize ideal electrochemical conditions.

At the electrodes a special polarization voltage is adjusted to realize a well-defined concentration ratio of the oxidized and of the reduced form of the redox catalyst. The time for the polarization, realized by means of the sensors integrated electronic device is approximately 5-10 minutes. If the ozone now passes the membrane, it reacts first chemically with the redox catalyst to form a reaction product followed by the electrochemically reduction of the reaction product at the working electrode. Caused by the polarization voltage the system is now endeavoured to adjust the former concentration ratio. This causes a current similar to the dissolved ozone amount of the sample. Besides, the current flow in the amperometric sensor leads to a rapid decrease of the analyte inside the sensor resulting in very fast response times also, if a rapid change from high to very low concentration levels is necessary.

All electrochemically working sensors have to be combined with a temperature measurement and the amperometric ozone sensor too. When ordering a multisensor measuring system for laboratory use or a complete submersible probe system, the temperature measurement and the temperature correction of the sensor signal is already included.

If measurements in a flow through system are required, special temperature sensors for the integration in AMT flow through cells are offered. When measuring in opened vessels or beakers in the laboratory, the customers has to realize the temperature measurement themselves.

If a calibrated sensor is ordered, the temperature correction is very easy by means of a factor or for more accurate measurements by means of a mathematical formula, delivered with the sensor.


feature specification
Measurement Principle Amperometric Clark-type Sensor
Measurement Range 0.2 mg/L to 10 mg/L O3 (linear range) others on request
Accuracy <2%
Resolution > 2 μg/l
Response Time (T90%) 4.5 to 9 seconds
Maximum Measurement Depth 100 m or 10 bar
Operating Temperature -2 °C to 30 °C
Signal Interference H2O2 when > 2% vol. No interference with oxygen or chlorine
Sensor Lifetime 5 to 10 months
Housing Titanium
Polarization Approx. 10 minutes
Power Supply 9 to 30 VDC
Output Linear: 0 to 3 VDC
Connector SUBCONN BH-4-MP
Physical Dimensions Diameter: 24 mm; Length: 235 mm