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Vaisala GMP251 CO2 Probe

The Vaisala CARBOCAP® Carbon Dioxide Probe GMP251 is an intelligent, stand-alone, % CO2-level probe. It is suitable for harsh and humid CO2 measurement environments where stable and accurate CO2 measurements are needed (for low “ppm” level CO2 measurements consider the Vaisala GMP252 CO2 Probe).  The operating temperature range is -40 … +60 °C and the measurement range is 0 … 20% CO2.  For applications in washdown atmospheres, we also have a Spray Shield (model: ASM212017SP) to protect the sensor from water ingress.

GMP252 incorporates an internal temperature sensor for compensation of the CO2 measurement according to ambient temperature. GMP251 is resistant to dust and most chemicals, such as, H2O2 and alcohol-based cleaning agents.

It can also be connected to the Indigo 200 series transmitters for an extended selection of outputs and configuration. There is also a blind relay box for switch outputs without the need for an inidigo transmitter.  The GMP251 replaces the now obsolete GMM221 and GMT221.


Vaisala GMP251 Features

  • Measurement range 0 … 20% CO2
  • Can be used for measurements even up to 30 000 ppm CO₂ with reduced accuracy
  • Intelligent, stand-alone probe with analogue (V, mA) and digital outputs (RS485 with Vaisala protocol or Modbus)
  • Can be connected with the Vaisala Indigo system for local display
  • Superior long-term stability with the 2nd-gen proprietary CARBOCAP® technology
  • Wide operating temperature range -40 … +60 °C
  • IP65 classified housing
  • Full temperature and pressure compensations
  • Integrated temperature measurement for CO₂ compensation purposes
  • Compensations for background gases: O₂, and humidity
  • Sensor head heated to prevent condensation


Vaisala GMP251 and GMP252 CO2 probes, Video


Fluidic are a recognised partner of Vaisala CEN (Industrial division) for Scotland and the North of England.  Our instrumentation engineers are product trained and able to help with instrument selection within the full range of Vaisala Carbon Dioxide, CO2 instrumentation.  Please call either office for more information (Glasgow 0141 641 5920,  Warrington 01925 572401).


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