Emerson Micro Motion SGM Series Configuration And Use Manual page 49

•
Procedure
1.
2.
3.
4.
5.
6.
Configuration and Use Manual
You must be prepared to flow all calibration gases through the device, at the
appropriate sample pressure. In a typical application, the sample pressure should be
approximately 25% greater than the control pressure.
Choose Device Tools > Calibration > Gas Calibration.
Set the measurement type for this device.
Option Description
Specific Gravity (SG)
Gas density will be measured as specific gravity, and specific gravity
will be used for calibration.
Molecular Weight (MW) Gas density will be measured as molecular weight, and molecular
weight will be used for calibration.
Relative Density (RD) Gas density will be measured as relative density, and relative density
will be used for calibration.
Set the calibration type (calibration format).
Option Description
2-Point Calibration (2 PT) Appropriate for gases with two main constituents. Requires two cal-
ibration gases.
3-Point Calibration (3 PT) Appropriate for gases with three main constituents. Requires three
calibration gases.
Select the number of the calibration that you want to perform.
The device can store up to four independent calibrations. All calibrations must have
the same calibration type (2-point or 3-point). Each calibration can use different
calibration gases.
Enter data for each calibration gas.
a. Select the calibration gas from the list. If it is not listed, select Other.
b. Enter the specific gravity, molecular weight, or relative density of the calibration
gas.
Tip
Enter the calibration gases in order of density, from lowest to highest. This allows heavier
gases to replace lighter gases.
Set the low-density calibration point.
a. Connect Calibration Gas Low to the pipework.
b. Set the pressure regulator on the calibration gas to the appropriate sample
pressure for your installation.
c. Open the calibration valve (Valve B) and the exit valve (Valve C).
Purging and calibration
41