Emerson Rosemount 2460, Справочное руководство

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85
Reference Manual
00809-0100-2460, Rev DE
Configuration
October 2018
Configuration
Floating roof correction
Upper limit
Above Upper limit the roof is fully floating and full compensation is made for
volume reduction.
Lower limit
Below the Lower limit when the roof rests on its legs no compensation of
volume is made.
Between Upper and Lower limit compensation is made through a weighted
value.
Weight
Volume compensation depends on roof weight and roof position.
Roof correction in TCT
If the roof correction is included in the Tank Capacity Table using a Base
density, a secondary correction will be calculated by the system hub. The
secondary correction will be based on the observed density, base density, and
volume adjustment.
Base density
This is the density at which the tank capacity table was specified. This value
can be found in the tank capacity table (tank certificate).
Volume adjustment
Volume adjustment from the tank capacity table (tank certificate).
LPG
Calculate LPG mass in air
Check this option to calculate as mass in air.
In the default setting, LPG vapor mass and product mass will be calculated as
mass in vacuum.
Molecular mass
Molecular mass of the product is used in calculation of vapor mass.
Compressibility factor The compressiblity factor is used in converting vapor volume to the
corresponding volume at standard temperature and pressure.
Vapor to liquid volume ratio For LPG products Vapor Volume Liquid Ratio (VLVR) is used for converting
vapor volume to liquid volume. This is used in calculations of Net Standard
Volume (NSV).
Item Description (continued)