Emerson 8800A, Product Manual

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Rosemount Model 8800C Vortex Flowmeter
3-10
User Defined Unit
User Defined Unit is a format variable that provides a record of the
flow units to which you are converting. The LCD on the Model 8800C
will display the actual units you define. The HART communicator will
simply display “SPCL.” There are four characters available to store the
new units designation.
Conversion Number
Conversion Number is used to relate base units to special units. For
a straight conversion of volume units from one to another, the
conversion number is the number of base units in the new unit.
For example, if you are converting from gallons to barrels and there are
31 gallons in a barrel, the conversion factor is 31. The conversion
equation is as follows (where barrels is the new volume unit):
1 barrel=31 gallons
NOTE
If reviewing parameters, the number is shown as the conversion factor
from base units to special units (i.e., 1/31).
Range Values
Range Values enables you to maximize resolution of analog output.
The meter is most accurate when operated within the expected flow
ranges for your application. Setting the range to the limits of expected
readings will maximize flowmeter performance.
The range of expected readings is defined by the Lower Range Value
(LRV) and Upper Range Value (URV). Set the LRV and URV within the
limits of flowmeter operation as defined by the line size and process
material for your application. Values set outside that range will not be
accepted.
Select each variable and enter the appropriate value. The new range is
defined by these values.
Process Temperature
Process Temperature is needed for the electronics to compensate for
thermal expansion of the flowmeter as the process temperature differs
from the reference temperature. Process temperature is the
temperature of the liquid or gas in the line during flowmeter operation.
NOTE
The temperature may also be changed under Calculate Density Ratio.
HART Comm. 1, 3, 3, 5, 3
HART Comm. 1, 3, 3, 5, 4
HART Comm. 1, 3, 4
HART Comm. 1, 3, 5