Starting at $2,904.00

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  • Measurement Range Options: 0 to 1000 ppm, 0 to 2000 ppm, 0 to 3000 ppm, 0 to 4000 ppm, 0 to 5000 ppm, 0 to 2%
  • Accuracy (25°C & 1013 hPa w/ 0.5% accurate gases)
    • 0 to 1000 ppm: ±(3 ppm + 1 % of reading)
    • All other Ranges: ±(5 ppm + 2 % of reading)
  • Repeatability (370 ppm)
    • Without output averaging: ±3 ppm CO2
    • With 30 s output averaging: ±1 ppm CO2

The Vaisala GMP343 carbon dioxide probe is an accurate and rugged probe designed for ecological measurements. Typical applications of the Vaisala GMP343 include CO2 soil respiration, ambient CO2 monitoring, plant growth chambers and OEM applications. Offering low power consumption and heat emission, the Vaisala GMP343 offers a single-beam, dual-wavelength CO2 measurement with no moving parts.

With the ability to output both numerically filtered and raw measurement data, Vaisala GMP343 carbon dioxide probes can also compensate the measurement with an internal temperature measurement and user-set relative humidity, pressure and oxygen values. In combination with an MI70 indicator (optional), the Vaisala GMP343 provides a tool for accurate in-site measurement. The optional MI70 indicator includes a rechargeable battery, AC adapter, MI70Link software with RS-232 cable (PC to MI70) and a 2 meter interface cable (GMP343 to MI70).

Each Vaisala GMP343 carbon dioxide probe is calibrated using ±0.5% accurate gases at 0 ppm, 200 ppm, 370 ppm, 600 ppm, 1000 ppm, 4000 ppm and 2%. Calibration of the GMP343 is also done at temperature points of -30°C, 0°C, 25°C and 50°C. If necessary, the customer can recalibrate the instrument using the multi-point calibration (MPC) feature allowing up to 8 user-defined calibration points.