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GFG CI21 for Ammonia in refrigeration plants

GFG CI21 for Ammonia in refrigeration plants


The transmitter CI21 has been specially designed for detection of ammonia in refrigeration plants. The detection principle “Charge Carrier Injection” (CI) combines the specificity of electro-chemical sensors with the longevity of chemosorption sensors.


Cross-sensitivities to lubricants, cleaning agents or hydrogen with the false alarms that occur as a result, are largely eliminated. The sensor signal remains stable over a wide temperature range. The transmitter can be operated at temperatures from -35°C to +55°C with a high degree of accuracy.  Ammonia leaks are rapidly detected. In less than 8 seconds an alarm is triggered, no matter if very low gas concentrations of a few ppm (1 ppm = 0.0001Vol%) or high concentrations in the % vol range are released. The transmitter CI21 covers a wide detection concentration and temperature range of operation, which other sensors do not provide.

  • Tech Info

    • Gas: Ammonia, NH3
    • Detection ranges: 30 .. 200 ppm 30 .. 1,000 ppm 50 .. 10,000 ppm
    • Gas supply: Diffusion through stainless steel mesh and PTFE membrane
    • Humidity: 1 .. 99 % r. h., non-condensing
    • Pressure: 800 .. 1200 hPa
    • Ambient temperature: -35°C .. +55°C
    • Response time: t90 less than 8 seconds
    • Casing protection: IP54, splash water proof  
    • Output signal: 0.2 .. 1 mA 4 .. 20 mA
    • Voltage supply: 10 .. 32 V
    • Cable: Shielded cable 3 x 0.75 mm2 for up to 500 m, 3 x 1.5 mm2 for more than 500 m, PG11 - cable gland
    • Weight: 370 g Dimensions: 82 x 77 x 57 mm (WxHxD)
    • Expected sensor life: 2 years for normal operation (independent from NH3 concentration)
  • Downloads

  • Delivery

    We aim to Delivery products with you within 4 weeks of receipt of order. However, in exceptional circumstances delivery may be up to 6 weeks due to manufacturer lead times. Please inform us if you require fast delivery as we will do our utmost to expedite your order.

  • Quantity Orders

    Please contact us directly to discuss quantity purchases and additional discounts.  We will subsequently provide you with a formal quote with the applied discount, which will be valid for 30 days 

  • Hire

    Many of the products you have seen are available for hire, so feel free to contact us if you would prefer to hire this instrument.

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