Series 3500/3510 EX

Explosion-Proof Oxygen Transmitter

Unmatched Technology & Value

Precision market leading trace and percent oxygen analyzers and transmitters can protect your process, plant and personnel

Our Alpha Omega Instrument Series 3500/3510™ EX Percent Oxygen Transmitter has a single range of 0-500, 0-1,000, or 0-10,000 ppm available online and looped powered at 14-32 VDC.  It is ideal for hazardous areas.

Series 3500/3510 EX includes

  • Accurate and dependable trace oxygen measurements in a variety of background gases
  • Long-life Ambient Temperature Electrochemical Sensor
  • NEMA 4 enclosure
  • 4-10 mADC output
  • Factory calibration, NIST calibration certificates available upon request

Standard Lead Time: Due to increased demand, current lead time is approx. 5 weeks.


  • Long Life Trace Oxygen Sensor: Provides up to three times the functional life of most “fuel cell” type sensors. Reliability is dramatically increased while maintenance costs are reduced.
  •  Sealed Sensor: Eliminates handling potassium hydroxide (caustic), a hazardous material or having to frequently “recharge” the electrolyte.
  •  CO2 Resistant Sensor: Optional CO2 resistant sensor is designed to operate with sample gases containing up to 100% CO2. Conventional “fuel cell” type sensors using potassium hydroxide (KOH) electrolyte can be poisoned from CO2.
  •  Affordable: Affords savings of up to 30% and more over other manufacturers trace oxygen transmitters.
  •  Wide Measurement Range: Measure from under 1 PPM to as high as 20,000 PPM oxygen.
  •  Factory Calibration: A factory Certificate of Performance Verification and Calibration is included at no additional charge. The product performance is verified in accordance with manufacturing specifications using a National Institute of Standards and Technology (NIST) traceable transfer calibrated standard gas mix.
  •  NEMA 4 Enclosure Greater installation flexibility with a dust and waterproof enclosure.


  • Measurement Ranges: (parts per million) 0-10, 0-50, 0-100, 0-500, 0-1,000, 0-5,000, 0-10,000, and 0-20,000
  • Accuracy¹: ±1% of full scale (± 5% of full scale on ranges ≤ 0-5 ppm)
  • Linearity: ±1% of full scale.
  • Response Time: 90% of full-scale response in less than 10 seconds (typical). The response time for ranges of 0-50 PPM or less depend to a great extent on the design of the sample delivery system including the materials used.
  • Sensor Type: Long-life Ambient Temperature Electrochemical Sensor (Optional CO2 Resistant Sensor Available).
  • Temperature Compensation: Standard.
  • Operating Temperature Range: 40° to 104°F (5° to 40°C) <40° F (<5°C) use heated sensor enclosure >104° F (>40°C) cooling of sample gas/sensor required
  • Warranty: Two years electronics one year sensor.


    • Polycarbonate, rated NEMA 4X (IP66) without optional equipment. (Optional NEMA7 explosion-proof enclosure available)
    • Dimensions: 5.5 in (139.9 mm) height. 8.8 in (223.5 mm) width. 3.4 in (86.4 mm) deep. Note: All dimensions are without optional equipment
    • Gas Connections: 1/4” stainless steel compression fittings.


    A nemesis for many conventional “fuel cell” type trace oxygen sensors are their inability to measure oxygen in gases containing carbon dioxide. Carbon dioxide reacts with potassium hydroxide electrolyte to form carbonic acid and in short time destroys the sensor. Not anymore. We offer an optional CO2 tolerant trace oxygen sensor with proprietary electrolyte. The CO2 tolerant sensor is capable of providing accurate oxygen readings in gases containing up to 100% CO2 without shortening the life of the sensor.


    Need help?  Complete our Oxygen-Application-Questionnaire.


    Need service on your AOI oxygen analyzer?  No problem.   We are ready to assist you with any technical or service-related inquiries.  Just complete our Oxygen Monitor RMA.

    Explosion-Proof Oxygen Transmitter with Long-Life Sensor 

    Process Insights_AOI_35003510 Explosion Proof Transmitter


    • Aerospace/Govt.
    • Bioreactors
    • Bio-Research
    • Bulk Industrial Gases
    • Chamber/Glove Box Manufacturers
    • Chemical
    • Chemical Storage
    • Combustion Control
    • Electrical Transformers
    • Fertilizers
    • Fiber Optic Research
    • Landfill


    Americas +1 713.947.9591
    EMEA +49 69 20436910
    China/APAC +86 400 086 0106

    Our Oxygen Monitors 

    Series 1300™

    Alpha Omega Instruments Oxygen Deficiency Monitor
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    Series 3000™

    Alpha Omega Instruments Trace Oxygen Analyzer 0-1 PPM to 0-10,000 PPM
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    Series 3500/3510™

    Alpha Omega Instruments Trace Oxygen Blind Transmitter 0-10 PPM to 0-20,000 PPM
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    Series 3520™

    Alpha Omega Instruments Portable Battery-Operated Trace Oxygen Analyzer
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    ZRO 2000™

    Alpha Omega Instruments Trace Zirconia Oxygen Analyzer PPM to 100%
    Process Insights_AOI ZRO 2000 oxygen analyzer


    Alpha Omega Instruments Percent Oxygen Analyzer 0-100% and 0-25%
    Process Insights_AOI-OXY-SEN oxygen analyzer

    Series 2000™

    Alpha Omega Instruments Percent Oxygen Analyzer 0-1 to 0-100%
    Process Insights_AOI_Series 2000 oxygen analyzer

    Series 2500/2510™

    Alpha Omega Instruments Percent Oxygen Transmitter 0-2% to 0-100%
    Process Insights_AOI_ Series 2510-Percent-Oxygen-Transmitter

    Series 2520™

    Alpha Omega Instruments Portable Percent Oxygen Analyzer 0-5, 0-10, 0-25, 0-50, and 0-100%
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    Questions? We’re here to help.