The Precisive® 5 Hydrocarbon Composition Analyzer is an infrared absorption based on-line monitoring system configured for measurement of alkanes: methane, ethane, propane, butanes and pentanes. It is a real-time optical analyzer capable of accurately separating the hydrocarbon components, which previously could only be performed by Gas Chromatograph (GC) analyzers. Using a unique wavelength-sweeping tunable filter spectrometer, fast update rates down to sub-second intervals are performed for the full C1 through C5 analysis. Sampling is a flow-through type, suitable for a continuous, on-line, unattended operation. This analyzer does not require carrier gas, fuel gases, or on-site calibration gases. The standard system configuration provides measurements of up to 100% methane, 25% of ethane, 25% of propane, 10% of butanes and 5% of pentanes.