The 871DO is a rugged dissolved oxygen sensor used for parts-per-million level measurements in industrial and municipal installations. Common applications include aeration basins, wastewater treatment plants, and aquaculture.
The 871DO sensor is housed in a thermoplastic body comprising PVDF and Noryl sections. It is a rebuildable style sensor with a tough stainless steel reinforced composite membrane bonded to an easily replaceable membrane cap. Membrane caps and replacement electrolyte are the only spare parts, and with regular maintenance the probe can last several years, even in the most difficult applications.
Installation of the 871DO dissolved oxygen sensor is accomplished through the use of built-in 1 inch NPT threads on the sensor body and the selection of an appropriate mounting adaptor. Most waste treatment applications are immersion or submersion style, so typically a standpipe is utilized. Foxboro offers handrail and ball float mounting assemblies to facilitate installation in treatment ponds and aeration basins.
In applications where sulfur containing gases are dissolved in the liquid stream, the 871DO resists poisoning of the reference electrode through the use of an isolated reference design. This design has proved robust in many industries, including pulp and paper.
When used with the 873DO analyzer, the 871DO offers several diagnostic routines, including membrane fouling, membrane breakage, and loss of internal filling solution.
