Teledyne’s LGA-4000Z series leverages the latest in Tunable Diode Laser Absorption Spectroscopy (TDLAS) to achieve an ultra-fast gas measurement in-line without resorting to extraction and sample conditioning. By tuning the laser to a specific absorption wavelength, based on the gas of interest, the attenuation of the light through a sample cell and the detector can be correlated to the concentration of each gas, per Beer-Lambert Law. The laser provides a narrow absorption band which minimizes the effect of interfering compounds in the process.
The System
The LGA-4000Z consists of a transmitter, receiver and connection box. The transmitter drives the tunable diode to emit a laser of a certain wavelength to pass through the environment being measured until it reaches the receiver. The receiver then performs a photo-electrical conversion, signal processing and spectrum data analysis to obtain the measuring result. The connection box, containing the I/O Interface, makes the connection of the power cable and the signal cable convenient.
Wavelength Modulation Spectroscopy (WMS)
WMS is a method used to significantly increase the sensitivity by reducing the low-frequency noise. The laser light’s intensity is modulated at a high frequency to create a periodic signal to the detector. The signal is then encoded and measured at a high frequency, eliminating the effect of low frequency noise.
Certifications
ATEX and IECEx Zone 1 IIC T6
Path Length
Typically 2-65 feet (0.6-20 meters), application-dependent
Repeatability
± 1% FS
Linearity
± 1% FS
Response
Typically < 1 second (application-dependent)
Utility Gases
Air or Nitrogen for purge (application-dependent), 30-115 psig (0.3-0.8 MPa)
Outputs
Analog: 2 x 4-20 mA (isolated), 750 ohm max load
Discrete: 2 x relay contact, Form-C type, rated 1A @ 24 VDC
Communications: RS-485 / RS-232
Inputs
2 x 4-20 mA (for pressure and temperature compensation)
Power
24 VDC 10 W
Temperature
-4° to 140°F (-20° to 60°C)
