ENMET IR-6000 - Manual (Page 4)

IR-6000 Hydrocarbon Sensor/Transmitter ENMET Corporation
2
2.0 Infrared Detection Technology
The IR-6000 Infrared gas detector uses infrared absorption technology for detecting combustible hydrocarbon gases. Gases
absorb infrared light only at certain wavelengths. The concentration of a gas can be measured by the difference of two channels
(wavelengths), a reference and a measurement channel. The
IR-6000 uses a collimated infrared light source that passes through
a waveguide, at the end of the waveguide is a dual channel receiver. The dual channel receiver measures the intensity of two
specific wavelengths, one at an absorption wavelength and another outside of the absorption wavelength. The gas
concentration is determined by a comparison of these two values.
Chart 1: Infrared Absorption Spectrum for Methane
The dual channel receiver is a single wafer, double filtered, dual receiver with an internal optical barrier. The elements are
perfectly matched resulting in overall stability and superior performance throughout the entire temperature range.
Diagram 1: Cutaway view of the IR-6000
Using a dual channel receiver there is no need to use any special lenses or beam splitters to achieve the different measurement
bands.
The IR-6000 utilizes a unique patent pending feature, the AutoAC
 circuit. The AutoAC circuit is an automatic analog
control circuit, which allows the IR-6000 to be calibrated for any combustible hydrocarbon, provided that a calibration quality
level of the gas is available. This eliminates setting dipswitches or changing out sensors for different types of hydrocarbons,
simply zero calibrate the unit with a calibration gas of the specific gas to be detected.
The optics can be easily disassembled for cleaning. This does not require powering the unit down and does not compromise the
units’ explosion proof rating.
There are no consumable components contained in this product.
T
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Wavelength
100%
0%
Absorption
Band
Reference
Band
Dual Channel
Receiver
Infrared Light
Source Waveguide
Window
Window
Waveguide
Collar
Wiring
Connections
Hydrophobic Filter