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S101 Diffusion O₂ Sensor

The S101 Diffusion Oxygen Sensor measures Oxygen concentration from 0-100% in a sealed chamber. Oxygen diffuses to the sensor from surrounding atmosphere. This sensor is the core of Qubit Systems' PH1LP Teaching Photosynthesis Package.

S101 Diffusion Oxygen Sensor is a Galvanic Cell (a lead-oxygen battery) consisting of a Lead Anode, an O₂ Cathode, and an Acid Electrolyte. It also incorporates an O₂-permeable Teflon FEP Membrane with a Gold Electrode bonded to its surface. Oxygen Diffusing through this membrane is reduced electrochemically at the gold electrode. The sensor can be fitted inside a sealed chamber for detection of O₂ gas diffusing across the membrane.

A Resistor and a Thermistor (for temperature compensation) are connected between the Anode and the Cathode, so that the battery is always discharged. The output of the instrument is proportional to the current flowing through the Resistor and Thermistor and to the partial pressure of O₂ in contact with the Teflon FEP Membrane. The signal from the Oxygen Sensor is transmitted to the computer via the Data Acquisition Interface and displayed in software as % O₂.

1. Features:
2. Simple One Point Calibration requiring Only Atmospheric Air
3. Output Linear
4. 90% Response in 12 seconds
5. Adjustable Gain
6. Output Range Adjustable from 0-25% = 5V
7. Temperature Compensation
8. Expected Sensor Life is 3 to 5 Years. Replacements are Inexpensive
9. Sensor is fitted with 1/8 inch Nylon NPT Union
10. Oxygen Sensor

1. Applications:
2. Measurements of photosynthesis in a sealed leaf chamber (integral component of the Teaching Photosynthesis Package PH1LP)
3. Monitoring of O2 levels in a closed chamber

1. Specifications:
2. Principle: Acid Electrolyte, Teflon Diffusion Membrane
3. Detection Range: 0-25% O₂ (Linear) Standard (can extend to 0-100%)
4. Resolution: ±50ppm
5. Accuracy: ±0.21% of Full Scale
6. Response Time (90%): 12 Seconds
7. Life Expectancy: 4-5 Years
8. Influence by Other Gases: Ammonia and Ozone
9. Required Sample Volume: Minimum of 2-3mL/min
10. Operating Temperature: 5 to 40°C (Effective Range)
11. Compensation: Built-in Temperature Compensation
12. Pressure Range: 0.5 atm to 1.5 atm
13. Pressure Effect: Output Voltage changes proportionally
14. Shock Resistant: to 2.7G
15. Vibration: Avoid Strong Vibration
16. Weight: 125gm
17. Output: 0-5 Volt Output
18. Power Supply: 5 Volts (Provided by Computer Interface)