Configure process measurement
Tip
Although configuring the temperature unit to match the temperature units used by your API
reference table is not required, Micro Motion recommends it.
5.
(Optional) If you want to use temperature data from an external temperature sensor:
a.
Set
Temperature Source
to
External
.
b.
Depending on your external setup, do one of the following:
• Set up polling for temperature
• Use digital communications to write temperature data to the sensor at appropriate intervals
• Configure the mA input to receive temperature data from an external measurement device
You can now configure your transmitter to report and handle petroleum measurement process variables
in the same way that it reports and handles other process variables.
5.9.1
Petroleum measurement application
The petroleum measurement application enables Correction for the effect of Temperature on volume of
Liquids (CTL), by calculating and applying a Volume Correction Factor (VCF) to volume measurement.
Internal calculations are performed in compliance with American Petroleum Measurement (API)
standards.
API reference tables are used to control how CTL is calculated. Your selection of
API Table Type
specifies
the type of process fluid that the calculations will assume, and the CTL source data, the reference
temperature, and the density unit that the calculations will use. Depending on your selection of
API Table
Type
, you may or may not need to specify
Reference Temperature
and
Thermal Expansion Coefficient
. See
Table 5-11 for a listing of the API reference tables and related information.
Table 5-11
API reference tables, associated process fluids, and associated calculation values
Table name
Process fluid
CTL source data
Reference
temperature
Density unit
5A
Generalized crude
and JP4
Observed density
and observed
temperature
60 °F (non-
configurable)
Degrees API
Range: 0 to 100
5B
Generalized
products
Observed density
and observed
temperature
60 °F (non-
configurable)
Degrees API
Range: 0 to 85
5D
Lubricating oils
Observed density
and observed
temperature
60 °F (non-
configurable)
Degrees API
Range: −0 to +40
6C
Liquids with a
constant density
base or known
thermal expansion
coefficient
User-supplied
reference density (or
thermal expansion
coefficient)
and observed
temperature
60 °F (non-
configurable)
Degrees API
92
Micro Motion 9739 MVD Transmitters