Emerson Micro Motion SGM - Page 54

The default value is 1.0. The range is 0.7 to 1.1.
c) Click Apply. No further actions are required.
4. If you set Compressibility Calculations to Enabled, complete the configuration as described in the
following steps.
5. Select the compressibility measurement method that you want to use or that meets site standards.
Important
• Different options are available depending on your primary process variable: specific gravity,
molecular weight, or relative density.
• If you choose AGA NX 19 Mod 3 or SGERG 88, you must set up energy content measurement. If you
choose any other method, energy content measurement is required only if you want the meter to
report calorific value, Wobbe index, or energy flow.
• Each compressibility measurement method has associated process limits. If your process goes
outside the valid range, compressibility will be reported as NaN (Not a Number), and all process
variables that require a calculated compressibility value will also be reported as NaN.
6. Set % CO2 Source to the method you will use to supply % CO2 data, and perform the required setup.
Option Description Setup
Polling The meter polls an external
device for % CO2 data.
a. Set % CO2 Source to Poll for External Value.
b. Set Polling Slot to an available slot.
c. Set Polling Control to Poll as Primary or Poll as Secondary.
d. Set External Device Tag to the HART tag of the % CO2
measurement device.
Digital
communications
A host writes % CO2 data to the
meter at appropriate intervals.
a. Set % CO2 Source to Fixed Value or Digital
Communications.
b. Perform the necessary host programming and
communications setup to write % CO2 data to the meter at
appropriate intervals.
Fixed value The configured fixed value is
used.
a. Set % CO2 Source to Fixed Value or Digital
Communications.
b. Set % CO2 (Fixed) to the desired value, in % by volume.
7. Set % N2 Source to the method you will use to supply % N2 data, and perform the required setup.
Configure process measurement using ProLink III Configuration and Use Manual
March 2021 MMI-20020954
54 Micro Motion Gas Specific Gravity Meters (SGM)