Connect To The Calibration Gas - Emerson Rosemount 370XA System Reference Manual

System Reference Manual
7P00370-H01
3.7

Connect to the calibration gas

The gas chromatograph requires a high quality, certified calibration
gas to ensure accurate analysis. Although the 370XA is typically set
for an automatic daily calibration run in custody transfer applications,
it can be configured with MON2020 for any time frequency, or set to
manual calibration only.
The calibration gas must contain each component that you want to
measure. To ensure that all of the components in the calibration gas
remain in the gas phase and that the composition remains consistent,
install a calibration bottle heater blanket and use insulated or heat-
traced stainless steel tubing between the calibration gas and the gas
chromatograph.
The following table recommends the ideal component concentrations
for a calibration gas that can be used with most common natural gas
applications. Also provided in the table is the minimum recommended
concentration for each component to ensure an accurate and
repeatable calibration.
Methane
Ethane
Propane
i-Butane
n-Butane
2,2 Dimethyl butane
neo-Pentane
iso-Pentane
n-Pentane
n-Hexane
Nitrogen
Carbon Dioxide
3 - 26
Component
89.57%
5.0%
1.0%
0.3%
0.3%
0.015%
0.1%
0.1%
0.1%
0.015%
2.5%
1.0%
Recommended
Concentration
370XA Gas Chromatograph
APRIL 2014