Emerson 8800C - Page 156

Rosemount Model 8800C Vortex Flowmeter
E-8
Example 3 (English units)
Fluid = Natural gas URV = 5833 SCFM
Line size = 3 in. LRV= 0 SCFM
Line press. = 140 psig C
20
= C
x
/sp. units factor (from Table D-4 on
page D-5)
Temp op. = 50 °F
'HQVLW\ r  OEF X IWRSH U
Viscosity = 0.01 cp
K-factor(compensated) = 10.797 (via HART communicator or AMS)
= 700/{10.797  (0.124675/10.71)}
= 5569.4 SCFM
Therefore, an input frequency of 700.00 Hz represents a flow rate of
5569.4 SCFM in this application.
For a given input frequency, you may also determine the current
output. Use the above example with an input frequency of 200 Hz.
URV= 5833 SCFM LRV= 0 SCFM F
in
(Hz) = 200.00
= 8.36 mA
Therefore, an input frequency of 200.00 represents a current
output of 8.36 mA.
I
FHz
() KC
20
() LRV–
URV LRV–
----------------------------------------------------------------
16
()
ÍÝ
ÌÜ
ÌÜ
ËÛ
4+=
200 10.797 0.011641 () 0– 
5833 0–
------------------------------------------------------------------------------
16
()
ÍÝ
ËÛ
4+