Panametrics Aurora H2O, User Manual

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Aurora H2O User’s Manual 11
Chapter 4. Programming Advanced Features
4.4 Set Up the Background Gas
4.4.1 Selecting the Type of Gas
The Aurora H2O TDLAS is normally calibrated to a standard gas mixture that is representative of “typical” natural gas.
The primary components and concentrations of this gas mixture are:
The process background gas is selectable from the
Settings Menu
.
• For normal operation in natural gas service, STD should be selected as the background gas.
• For verification testing in pure methane , select CH4 .
• If verifying in Nitrogen with a known moisture concentration, N
2
should be selected as the background gas.
The Aurora H2O displays the selected Background Gas an indicator in the upper right
corner of the LCD, adjacent to the status message.
Unless otherwise requested, the Aurora H2O is shipped from the factory configured
for Methane operation.
To change the type of background gas, from the Settings Menu select Gas and press
Enter . The following screen appears.
Component Concentration
Methane (CH4) 90.0%
Nitrogen (N
2
) 10.0%