Model 4000 Percent Oxygen Sensor

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STABLE, RELIABLE amperometric Oxygen Sensor LONG LIFE, LOW MAINTENANCE rechargeable sensor ROBUST DESIGN RAPID CALIBRATION using ambient air COMPATIBLE WITH 5081-A AND 1055 INSTRUMENTS

APPLICATIONS The Model 4000 sensor is used to monitor percent oxygen concentrations in gaseous streams. The most common use is to monitor oxygen headspace concentration for nitrogen blanketing applications. The sensors are also used in other applications where oxygen levels are controlled and monitored. FEATURES The Model 4000 Series Percent Oxygen sensor is a membrane-covered amperometric sensor. The membrane consists of a gas permeable Teflon®1 membrane stretched tightly over a gold cathode. A silver anode and an electrolyte solution complete the internal circuit. The sensor body is constructed of Ryton®2, which can withstand exposure to hydrocarbons and other corrosive chemicals. Gas permeates through the membrane, and the oxygen in the sample is reduced at the cathode. A voltage is applied across the cathode and anode, generating an electrical current that is directly proportional to the oxygen concentration in the sample. Since the rate of oxygen diffusion through the membrane is temperature dependent, the sensor response must be corrected for permeability caused by temperature. A Pt 100 RTD in the sensor accurately measures temperature, and the analyzer automatically performs the correction. The sensor is easy to maintain. For calibration simply expose the sensor to ambient air and press the air calibration button. The analyzer measures the barometric pressure using an on-board pressure sensor and calculates the equilibrium solubility of atmospheric oxygen at the prevailing temperature and pressure. Replacing the membrane requires no special tools or fixtures. To replenish the electrolyte solution, unscrew the fill plug, add the reagent, and replace the plug.