Long-term-stable sensors monitor oxygen levels

July 06, 2016 // By Graham Prophet
SST Sensing’s Zirconia Miniature series of sensors, in 12mm diameter metal cans, are 5-pin devices that measure oxygen levels in virtually any environment, providing accuracy over a prolonged period.

Response time is as little as 4 seconds and oxygen range is from 0.1% to 100%. They can operate in oxygen pressures from 2 mbar to 3 bar with superior accuracy and linearity. Among the key target application areas for these devices are - combustion control in industrial boilers, ensuring the quality of perishable goods during transportation, controlling industrial composting processes and in both oxygen generating and inerting systems in aircraft.

 

SST’s zirconium dioxide (ZrO 2) based sensors are able to keep generating exact, reliable data across an extensive operational lifespan, even in the most challenging of environments, including high temperatures (up to 400°C), humidity conditions and oxygen pressures. They are not susceptible to depletion over time, thereby reducing the repair and replacement costs involved.

 

While conventional zirconia oxygen sensors on the market rely on sensing cells that utilize either an oxygen ion pump or the Nernst Effect, the sensors produced by SST incorporat both mechanisms in tandem. This has major operational benefits, not only in terms of enabling improved performance but also providing the diagnostics needed to allow any effect on system performance to be promptly identified and addressed. Combining these mechanisms means that the need to include a sealed reference gas or temperature stabilisation can be dispensed with. The resultant oxygen sensing system thus takes up considerably less space and its application versatility is improved. It makes recalibration very simple to carry out.

 

SST Sensing (Coatbridge, Scotland); www.sstsensing.com