Emerson Network Router - Manual (Page 52)

46 ProLink ® II Software for Micro Motion ® Transmitters
Transmitter Configuration, Characterization, and Calibration
5.3.1 Using the Gas Unit Configurator tool
Note: For Model 2400S transmitters, and for Series 1000/2000 and LF-Series transmitters with
firmware version 5.0 and above, the Gas Unit Configurator tool is not available because standard
and normal units are pre-defined in the transmitter.
For many gas applications, standard or normal volume flow rate is used as the quasi mass flow rate.
Standard or normal volume flow rate is calculated as the mass flow rate divided by the density of the
gas at a reference condition.
To configure a mass flow special unit that represents standard or normal volume flow rate, you must
calculate the mass flow conversion factor from the density of the gas at a reference temperature,
pressure, and composition. ProLink II v1.2 and later offers a Gas Unit Configurator tool to calculate
this mass flow conversion factor. The tool will automatically update the mass flow conversion factor
in the
Special Units tab.
Note: Micro Motion recommends that you do not use the meter to measure actual volume flow of a
gas (volumetric flow at line conditions). If you need to measure actual volume flow of a gas, contact
Micro Motion customer support.
To use the Gas Unit Configurator:
1. Choose Tools > Gas Unit Configurator .
2. Select the Time Unit that your special unit will be based on.
3. Select either English Units or SI Units .
4. Click Next .
5. Define the standard density to be used in calculations.
• To use a fixed standard density, click the top radio button, enter a value for standard
density in the
Standard Density box, and click Next .
• To use a calculated standard density, click the second radio button and click Next . Then
enter values for Reference Temperature , Reference Pressure , and Specific Gravity on
the next panel, and click Next .
6. Check the values displayed.
• If they are appropriate for your application, click Finish . The special unit data will be
written to the transmitter.
• If they are not appropriate for your application, click Back as many times as necessary to
return to the relevant panel, correct the problem, then repeat the above steps.
CAUTION
The meter should not be used for measuring the actual volume of gases.
Standard or normal volume is the traditional unit for gas flow. Coriolis meters
measure mass. Mass divided by standard or normal density yields standard or
normal volume units.