Rosemount 8800D Series User Manual

Reference Manual
00809-0100-4004, Rev BA
August 2010
Rosemount 8800D
3-10
Density Ratio
Configure the Density Ratio in one of two ways:
1. Enter Density Ratio to convert from actual flow rate to standard flow
rate.
2. Enter the process and base conditions. (The Rosemount 8800D
electronics will then calculate the density ratio for you).
NOTE
Be careful to calculate and enter the correct conversion factor. Standard flow
is calculated with the conversion factor you enter. Any error in the factor
entered will result in an error in the standard flow measurement. If pressure
and temperature changes over time, use actual volumetric flow units. The
Rosemount 8800D does not compensate for changing temperature and
pressure.
NOTE
Changing the base process conditions will modify the density ratio. Likewise
a change to the density ratio will lead to a change in the base process
pressure (Pf).
Density Ratio
Density Ratio is used to convert actual volumetric flow to standard volumetric
flow rates based on the following equations:
Calculate Density Ratio
Calculate Density Ratio will calculate the density ratio (shown above) based
on user entered process and base conditions.
Operating Conditions
T
f
= absolute temperature at actual (flowing) conditions in degrees Rankine or
Kelvin. (The transmitter will convert from degrees Fahrenheit or degrees
Celsius to degrees Rankine or Kelvin respectively.)
P
f
= absolute pressure at actual (flowing) conditions psia or KPa absolute.
(The transmitter will convert from psi, bar, kg/sqcm, kpa, or mpa to psi or kpa
for calculation. Note that pressure values must be absolute.)
Z
f
= compressibility at actual (flowing) conditions (dimensionless)
Field Comm. 1, 3, 2, 4, 1
Field Comm. 1, 3, 2, 4, 1, 1
Field Comm. 1, 3, 2, 4, 1, 2
Field Comm. 1, 3, 2, 4, 1, 2, 1
DensityRatio
density at actual (flowing) conditions
density at s dard (base)tan conditions
--------------------------------------------------------------------------------------------------------=
DensityRatio
T
b
xP
f
xZ
b
T
f
xP
b
xZ
f
---------------------------=

Rosemount 8800D Series Specifications

General

Type	Vortex Flow Meter
Measurement Principle	Vortex Shedding
Operating Temperature	-40 to 185°F (-40 to 85°C)
Storage Temperature	-40 to 185°F (-40 to 85°C)
Communication Protocols	FOUNDATION Fieldbus
Material	316 stainless steel
Fluid Type	Liquid, Gas, Steam
Line Size	1/2 to 8 inches (15 to 200 mm)
Approvals	ATEX, IECEx, CSA, FM
Output Signal	4-20 mA
Process Connection	Flanged, Wafer, Threaded
Electrical Connection	M20
Protection Rating	IP66
Mounting Style	Wafer, Flanged