Emerson Process Management 3422 User Manual

June 2013

3-9000-743 Rev S

1.

From the 

, choose the desired settings:

•

AGA8 calculations to be performed:

—

Internally (by meter)

—

Base temperature

—

Base pressure

—

Base absolute pressure

—

Externally

—

Fixed

—

Live 

Gross Method 1

Specific gravity: Relative density; used as input to the AGA8 Gross Methods 1 and 2 calculations

•

Reference temperature - for the specific gravity

•

Reference pressure - for specific gravity

•

CO2 - Mole percentage CO2 in the natural gas mixture

•

Hydrogen - Mole percentage of hydrogen

•

CO - Mole percentage of carbon monoxide

Volumetric gross heating

•

Molar density ref temperature: Reference temperature for the molar density; used as 

input to the AGA8 Gross Method 1 calculation

•

Molar density ref pressure: Reference pressure for the molar density; used as input to the 

AGA8 Gross Method 1 calculation

Gross Method 2

Specific gravity: Relative density; used as input to the AGA8 Gross Methods 1 and 2 calculations

•

Reference temperature - for the specific gravity

•

Reference pressure - for the specific gravity

•

CO2 - Mole percentage CO2 in the natural gas mixture

•

Hydrogen - Mole percentage of hydrogen

•

CO - Mole percentage of carbon monoxide

•

Nitrogen - Mole percentage of nitrogen in the natural gas mixture (AGA8 Gross Method 2 

calculation)

Detail

Enter the amount of each of the 21 gas components as a percentage. 
This option is only available in Mark III meters

•

Gas composition - Select either the Fixed or Live GC.

–

Fixed: Select this option to use the fixed gas composition stored in the meter for all 

calculations for which they are required.

–

Live GC: Select this option to use a gas composition collected by the meter from a 

gas chromatograph for all calculations for which they are required. This option is 
only available for Mark III meters with a valid GCKey

Externally 

•

Select if AGA8 calculations are done externally. The calculated values must then be 

written to the meter using Daniel MeterLink or a flow computer. The following properties 
must be entered. If a flow computer or SCADA system is used to write these values to the 
meter, they do not have to be entered at this time.

–

Flow mass density

–

Flow compressibility

–

Base compressibility

Note: Mark II meters - Externally calculating the AGA8 calculations is only available for DFI boards running version 3.40 or later 
firmware.