Sensor cuts cost of dissolved oxygen measurement

Problems associated with traditional dissolved oxygen sensing systems can now be eliminated using ABB’s new optical dissolved oxygen sensing system, according to the firm.


Consistent, reliable and accurate, it can help operators to realise significant savings through reduced energy consumption and maintenance.
Comprised of the ADS430 sensor and multi-channel transmitter, the system provides the highest levels of stability and accuracy for dissolved oxygen measurement. The ADS430 optical dissolved oxygen sensor uses Rugged Dissolved Oxygen (RDO®)* optical technology for measuring dissolved oxygen in the most demanding process environments. The RDO technology, which has been approved by the US Environmental Protection Agency (EPA), uses the dynamic luminescence quenching technique. Comprised of a sensor and multi-channel transmitter, it works on the frequency domain method and provides the highest levels of stability and accuracy for dissolved oxygen measurement.
The patented signal processing within the sensor enables it to respond to changes in process conditions up to five times faster than other optical systems, allowing maximum process savings through improved control.
The robust design of the sensor enables it to withstand the problems that can affect conventional membrane-based sensors, such as abrasion, fouling or poisoning. Constructed from inert, non-corrosive materials, it is suitable for use in high salinity environments. The sensor lumiphore is not affected by photobleaching or stray light. The sensor itself is also immune to the effects of sulfides, sulfates, hydrogen sulfide, carbon dioxide, ammonia, pH, chloride and other interferences that can affect membrane-based sensors.
The use of the dynamic luminescence quenching principle means that the sensor is not susceptible to drift, removing the need for frequent maintenance.
A key benefit of the system is its simplicity. ABB’s EZLink plug and play technology automatically connects the transmitter and sensor, with no need for wiring or complicated configuration.
Set-up is straightforward, with a user friendly HMI and clear menus making it easy to set parameters and view diagnostic information.
Available in two or four channel versions, the Aztec AWT440 universal transmitter can be connected to up to four ABB digital sensors, enabling monitoring at multiple points without purchasing and installing separate transmitters. This simplicity also extends to the sensor itself, which features a smart sensing cap with automatic setup. The SmartCap comes pre-loaded with factory calibration coefficients, serial number, lifetime indication, and manufacture date which are automatically uploaded to the sensor, eliminating the time normally required for set-up.