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CL2-A1 Alphasense 20ppm Chlorine Gas Sensor

CL2-A1 Alphasense 20ppm Chlorine Gas Sensor
Regular price $172.00

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The CL2-A1 Alphasense Chlorine Gas Sensor is a 20mm diameter sensor, designed to monitor CL2 concentrations to prevent injury to those working around the gases presence. CL2 sensors are available in a wide range of formats and are suitable for use in both fixed and portable gas detection.

The CL2 range provides OEMs with reliable sensing for use in a number of high volume applications. Strong signal levels combined with low zero current allows resolution to 20ppb and an operating range from +0 to 20ppm. 

Chlorine gas sensors are also commonly used due to their electrolyte leak-free guarantee and reliable long-term detection performance. The leakproof housing is molded with a color coded top for ease of identification.


  • Accurate, Quality EC sensor
  • Low Cross-Sensitivity across multiple gases
  • Easy to use and integrate into portable or fixed gas detectors
  • Used in water, treatment, industrial, wastewater, and many other applications
  • No external power required, low maintenance
  • Proven and trusted design - 90 day warranty


  • Sensitivity: nA/ppm in 10ppm CL2 -350 to -750
  • Response time: t90 (s) from zero to 10ppm CL2 ((33Ω load resistor) <60
  • Zero current: ppm equivalent in zero air < ±0.4
  • Range: ppm limit of performance warranty 20
  • Linearity: ppm error at full scale, linear at zero and 5ppm CL2 ±1.5
  • Overgas limit: maximum ppm for stable response to gas pulse 50
  • Zero drift: ppm equivalent change/year in lab air, monthly test <0.05
  • Sensitivity drift: % change/year in lab air, monthly test < 10
  • Operating life: months until 80% original signal (24 month warranted) > 24
  • Sensitivity@ -20°C % (output@ -20°C/output@ 20°C) @10ppm CL2 65 to 85
  • Sensitivity@ 50°C % (output@ 50°C/output@ 20°c) @10ppm CL2 105 to 125
  • Zero@ -20°C ppm equivalent change from 20°c | <±0.2
  • Zero@ 50°C ppm equivalent change from 20°c | < 0 to -0.8
  • Temperature range °C: -20 to 50
  • Pressure range kPa: 80 to 120
  • Humidity range %RH continuous 15 to 90
  • Storage period months: @ 3 to 20°c (stored in sealed pot) 6
  • Load resistor: olms (recommended) 33
  • Weight grams: < 6
  • H2S sensitivity % measured gas@ 20ppm H2S  < -300
  • H2 sensitivity % measured gas@ 400ppm H2 < 0.1
  • NO2 sensitivity % measured gas@ 10ppm NO2 100
  • NO sensitivity % measured gas@ 50ppm NO < 3
  • SO2 sensitivity % measured gas@ 20ppm SO2 < -8
  • C2H4 sensitivity % measured gas@ 400ppm C2H4 < 0.1


    • 90 Days - See CO2Meter Terms and Conditions

    Tube cap adapters easily convert 20mm standard gas sensors from diffusion to sampling sensors. Molded polymer grips sensor for easy fit and removal while maintaining a good seal.

    Micro-Pump Kit includes all the tools you need to urilize the tube-cap adapters as part of a sampling sensor system.

    Nafion tubing is a highly selective, semi-permeable membrane to water vapor. If gases inside Nafion tubing are wetter than gases surrounding the tubing, drying will occur. If the surrounding gases are wetter, humidification will occur.

    Micro gas sampling pumps provide a constant flow of air across the sensor with a tube cap - perfect for bench-top testing of sensors for closed-loop sampling applications.

    Sensor Pin Sockets - Manufacturers do not recommend soldering to the pins. Pin sockets can be purchased from Andon distributors. Click here to search for your sensor's socket. Select the brand PDF, find your sensor, then search for the Andon part number for your sensor's socket.

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    Customer Reviews

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    "Easy to install, easy to set up, and easy calibration - just what I was looking for."

    - Phillip Farrar
    Water Plant Superintendent

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