Solid state oxygen sensors address ecological Demands

The optically-based, factory-calibrated LuminOx sensors rely on fluorescence quenching by Oxygen. Here, pulsed light is directed onto an oxygen-sensitive fluorescent dye causing it to fluoresce. The rate at which this fluorescence decays is inversely proportional to the amount of oxygen present in the vicinity.

Because the phenomenon does not deplete the fluorescent dye, LuminOx devices can be deployed for far more prolonged periods than are possible using conventional oxygen sensors in this price bracket (which are normally based on electrochemical measurement mechanisms which rely on an electrolyte which is “consumed” over time).

They can remain in service of well over 5 years. Furthermore, LuminOx sensors are completely free from lead, liquid electrolytes and other hazardous materials that are present in electrochemical sensing solutions - which have significant environmental concerns associated with them.

LuminOx devices are suitable for measuring oxygen in terms of either partial pressure (ppO2) or oxygen concentration (vol. %). LuminOx is fully compensated for temperature and barometric pressure. Running from a standard 5V supply, these sensors draw a current of <6mA when acquiring sampling data at a rate of 1sample/s.

Standard sensors operate from 0-25% vol. O2 and a high degree of accuracy is maintained across this range (with better than 2% full scale achieved). They support a working temperature range spanning from -30°C to +60°C, making them considerably more robust than competing devices.

Providing a simple 3.3V TTL output across an RS232 serial interface, they can be connected directly to the system microcontroller with no need for additional signal conditioning electronics. The compact form factor of these sensors means that they can easily be used to replace older generation sensor devices while keeping the same housing format.

“The LuminOx family is significantly more resilient to environmental effects than electrochemical oxygen sensors, with the ability to deal with wider operating temperatures, as well as rapid changes in pressure,” states Paddy Shannon, SST Sensing’s Technical Director.

“As a result they provide the market with a much more stable oxygen sensing solution that combines low cost, minimal power consumption and simple installation with longer life and full RoHS compliance from the outset.”

SST Sensing’s LuminOx optical oxygen sensors have a robust construction in order to survive in challenging environmental conditions. Typical applications types include - portable equipment, breathing apparatus, laboratory equipment, incubation systems, perishable goods transportation, combustion processes, agriculture, inerting and fire prevention.