Vaisala GMP251 Carbon Dioxide Probe
Starting at $717.00

Not in stock. Usually ships in 1-2 weeks [?]

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  • 0 to 20% CO2 measuring range
  • Accuracy ±0.1 to ±0.4 %CO2 (at 25°C and 1013 hPa)
  • Analog (V, mA) and digital (RS485) outputs
  • Long-term stability with CARBOCAP technology
  • -40 to 140°F (-40 60°C) operating temp
  • IP65 classified housing
  • Full temperature and pressure compensations
  • Calibration certificate included

The Vaisala GMP251 Carbon Dioxide Probe is designed for use in demanding applications, like life science incubators, where stable, reliable, and accurate performance is required. The GMP251 is based on Vaisala's unique, second-generation CARBOCAP® technology that enables exceptional stability. A new type of infrared (IR) light source is used instead of the traditional incandescent light bulb, which extends the lifetime of the GMP251.

The GMP251 incorporates an internal temperature sensor for compensation of the CO2 measurement according to ambient temperature. The effects of pressure and background gas can also be compensated for. The measurement range is 0 to 20% CO2 and the sensor performance is optimized at 5% CO2 measurement. The operating temperature range of the probe is wide and the probe housing is classified as IP65. Condensation is prevented as the internal sensor head is heated. The GMP251 is resistant to dust and most chemicals, such as, H2O2 and alcohol-based cleaning agents.

The GMP251 is a compact probe that is easy and fast to install in a number of ways. It's easy to plug in and plug out. The surface of the The intelligent, stand-alone carbon dioxide probe GMP251. probe is smooth, which makes it easy to clean. The probe provides several outputs for the CO2 measurement, analog current and voltage outputs as well as digital RS485 with Modbus protocol.

Vaisala Indigo 200 Series Transmitter
Plug-and-play connection for compatible CO2, vaporized hydrogen peroxide, humidity & temperature probes
Vaisala 242659 Connection Cable
M12/5 N female to USB cable used to connect Indigo probes to a PC for use with Insight software
In Stock
Vaisala ASM211650SP Membrane Filter
PTFE membrane covering a PET plastic grid, 25mm diameter female thread
Vaisala DRW243649SP Porous Sintered PTFE Filter
Ø25 mm female thread, extra protection for GMP251 CO2 Probe
Vaisala Indigo Compatible Probe Cable
Shielded 5-socket M12 female connection to open wire
In Stock
Vaisala ASM211697SP Flow Through Adapter
Inlet and outlet gas ports allow for a controlled gas feed to the GMP251 CO2 sensor
Vaisala Indigo Compatible Right Angle Probe Cable
90° shielded 5-socket M12 female connection to open wire
Vaisala 243257SP Probe Mounting Clips
2 metal clips and screws for mounting GMP251 or GMP252 probes
Vaisala 243261SP Probe Mounting Flange
60mm diameter flange with o-rings, gasket, and 4 screws for mounting GMP251 and GMP252 probes through a wall or surface
Vaisala CBL210472 MI70 Connection Cable
M12/5 N female to M12/4 male connectors for hooking GMP251 and GMP251 CO2 probes to the MI70 handheld indicator
Vaisala CBL210493SP Flat Cable
M12 5-pin, 3.3ft (1m) flat extension cable for temporary connections to GMP251 and GMP252 CO2 probes through a tight space
Vaisala DRW244827SP Calibration Adapter
Allows feeding reference gas to the probe through the adapter’s gas port when calibrating, suitable for tubing with 4mm inner diameter
Vaisala ASM212017SP Spray Shield Adapter
IPX9 rating, protects the GMP251 / GMP252 carbon dioxide probe from pressure water jets
Vaisala DTR250 Radiation Shields
Recommended accessory for GMP251 and GMP252 probes when used for outdoor CO2 measurements