Partial oxygen measurement system

Abstract

A partial oxygen pressure measuring system for quantitating the amount of dissolved oxygen in solution of a fluid sample. The system includes a sensor electrode within which a volume of fluid whose oxygen is to be measured is inserted. The sensor has a silver chlorided tube with an insulated nickel wire of reduced diameter passing coaxially and internal thereto. The nickel wire terminates in an end section which is platinum plated to form a polarizing surface. Both the silver chloride tube and wire pass external to the sensor and are electrically coupled to a pair of contact rings which represent cathode and anode junctions respectively. A biasing voltage is placed across the contact rings to form a circuit path through the wire, platinum coated surface, fluid sample and base reference silver chlorided tube in order to determine the current flow which is a measure of the oxygen level in the fluid sample. The system further includes a resistance thermal device in combination with a heater assembly in order to heat the fluid sample to a predetermined temperature and maintain it for a predetermined time interval. Both the voltage application and the heating assembly are initiated simultaneously by the closing of a lid of a portable housing within which the sensor is inserted. After a time interval, subsequent to the housing lid closure, a display of the partial oxygen pressure in the fluid sample is provided.