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Gas properties
Section 6: Meter operation
 Reference, Installation, and Operations Manual
June 2013
3-9000-743 Rev S
6.1.16
Gas properties
Gas property data (composition and heating value) are used by the meter for AGA8 calculations 
(for converting to base or standard volumes and for mass calculation), for energy calculation, 
and for optional AGA10 calculations (sound velocity calculation and comparison). The data are 
also used by JuniorSonic meters when the profile correction factor is to be calculated by the 
meter (rather than fixed or a default value). 
 for GC registers polled by the meter.
The gas property data can either be fixed (specified via data points) or optionally read from a 
Daniel gas chromatograph (GC). Reading the gas property data from a GC requires both the 
Option Board (Port C) and a valid GC feature key (
Fixed gas property data
If the data is fixed, then the heating value and its reference temperature are specified via the 
MeasVolGrossHeatingVal and RefTemperatureHV data points, respectively; the gas 
components are specified via the data points listed in 
 below. Fixed gas property data is 
always assumed to be valid.    
if the gas composition is specified from within Daniel MeterLink, the data points’ unit is mole 
percentage, not mole fraction (as the data point name would imply).