Emerson Micro Motion SGM Series - Page 117

Options for HART variables (continued)Table 10-7:
Process variable
Primary Varia-
ble (PV)
Secondary
Variable (SV)
Third Variable
(TV)
Fourth Varia-
ble (QV )
Net Mass Flow Rate ✓ ✓ ✓ ✓
Net Volume Flow Rate ✓ ✓ ✓ ✓
Gas measurement
Base Density (Gas) ✓ ✓ ✓ ✓
Specific Gravity (Gas) ✓ ✓ ✓ ✓
Relative Density (Gas) ✓ ✓ ✓ ✓
Molecular Weight (Gas) ✓ ✓ ✓ ✓
Compressibility ✓ ✓
%CO
2
✓ ✓ ✓ ✓
%H
2
✓ ✓ ✓ ✓
%N
2
✓ ✓ ✓ ✓
%CO ✓ ✓ ✓ ✓
Energy measurement
Calorific Value ✓ ✓ ✓ ✓
Wobbe Index ✓ ✓ ✓ ✓
Energy Flow ✓ ✓ ✓ ✓
Interaction of HART variables and transmitter outputs
The HART variables are automatically reported through specific transmitter outputs. They
may also be reported through HART burst mode, if enabled on your transmitter.
Restriction
One some devices, the PV and the primary mA output are fixed to a specific process variable and
cannot be changed.
HART variables and transmitter outputsTable 10-8:
HART variable Reported via Comments
Primary Variable (PV) Primary mA output If one assignment is changed, the other is changed auto-
matically, and vice versa.
Secondary Variable (SV) Secondary mA output, if
present on your transmitter
If you have a secondary mA output: If one assignment is
changed, the other is changed automatically.
If you do not have a secondary mA output: The SV must be
configured directly, and the value of the SV is available on-
ly via digital communications.
Tertiary Variable (TV) Not associated with an out-
put
The TV must be configured directly, and the value of the
TV is available only via digital communications.
Integrate the meter with the control system
Configuration and Use Manual 109