SENSIT Technologies GAS-TRAC LZ-30, Инструкция по эксплуатации

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SENSOR TECHNOLOGY
G
AS
D
ETECTION
The
GAS•TRAC LZ-30
uses open path TDLAS (tunable diode laser absorption
spectroscopy) technology. The laser generates a specific wavelength of light
that is sent through the gas monitoring area, partially absorbed by any
methane source, and reflected back to the instrument by the reflection surface.
The higher the methane concentration, the larger the absorption will be,
resulting in a higher reading. Using this technology in an open path allows for
the instrument to detect gas remotely, simply by pointing at the target
anywhere from 0.5 to 30 meters away from the operator.
D
ISTANCE
D
ETECTION
There is a separate laser that is used specifically for distance detection. It
sends a laser pulse to the target in a narrow beam and measures the time
taken from when it leaves the instrument to when it returns, from the reflection
surface. Using this time measurement, the distance is determined based on
the speed of light.
Both the distance and gas detection rely on a surface that is reflective enough
to return the signal to the instrument. Most solid surfaces will work. Changes
in reflectivity can cause variance in both the gas and distance measurements.