bv/GAS 7500/7000 Caracteristiques

	GAS ANALYSERS
Bibliography LI-820 LI-840 LI-7000 Information Contacts Gas Analysers	The LI-7500 Open Path CO₂/H₂0 Analyser
	The unique design of the new LI-7500 Open Path CO₂/H₂O Analyser will give scientists an alternative to the closed path analyser when power is a major design consideration as it will eliminate to need for a pump. When mounted above a canopy the open path design allows air to naturally flow unimpeded through the analyser which is mounted along side a sonic anemometer. An open path analyser not only eliminates the need for a pump but also eliminates the need to compensate for delays from the time the air is sampled at the end of the tube to the time it s pumped into the analyser to determine the CO₂ concentration. The LI-7500 was designed primarily for flux applications. For this reason, specifications and features were optimised for this application. Some of these include : high speed electronics for bandwidths of 5, 10 or 20 Hz, high precision, low noise, aerodynamic profile, easy mounting, etc. Upon request, LICOR can certify operation of the LI-7500 to -40°C. The normal temperature operating range is -25 to +50°C. If your are concerned by very low temperature operating for LI-7500, please contact us.
	The LI-7000 Closed Path CO₂/H₂0 Analyser
	Although the LI-7500 was designed for flux measurements, it is not necessarily the analyser of choice for all flux applications. The new LI-7000 was also designed for flux measurements and is better suited for some applications. The LI-7000 has a 5 to 10 times better noise specifications than the LI-7500 making it better suited to measuring small fast eddies such as is encountered over shorter and smoother canopies. The electronics in the LI-7000 are as fast as the LI-7500. Better accuracy than the LI-7500. The LI-7000 can be auto-calibrated during measurements. The LI-7500 cannot be auto-calibrated as it requires the physical placing of a shroud in the optical path. The optical path can be removed for cleaning and reassembled without the need for factory calibration.
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