Emerson 8600 Gas Heater User Manual


 
127
Reference Manual
00809-0100-4860, Rev BC
Appendix C: Electronics verification
January 2013
Electronics verification
For a given input frequency, you may also determine the current output. Use the Example 2 on
page 126 with an input frequency of 300 Hz:
URV= 40000 lb/hr LRV= 0 lb/hr F
in
(Hz) = 300.00
= 9.83 mA
Therefore, an input frequency of 300.00 Hz represents a current
output of 9.83 mA.
Example 3 (English units)
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 Hz represents a current output of 8.36 mA.
Fluid = Natural gas URV = 5833 SCFM
Line size = 3 in. LRV = 0 SCFM
Line pressure = 140 psig C
20
= C
x
/sp. units factor
(from Table C-1 on
page C-125
)
Operating
Temperature
= 50 °F Density () = 0.549 lb/cu-ft
(oper)
Viscosity = 0.01 cp Input
Frequency
= 700 Hz
K-factor
(compensated)
= 10.678 (via Field
Communicator or AMS)
Q = F(Hz) /(K x C
20
) where: C
20
= C
12
/10.71 (Density Ratio)
= 700/{10.797 x (0.124675/10.71)}
= 5569.4 SCFM
I
FHzK C
17
LRV
URV LRV
------------------------------------------------------
16


4+=
I
300 10.678 0.00192760
40000 0
--------------------------------------------------------------------------------------
16



4+=
I
FHzKC
20
 LRV
URV LRV
----------------------------------------------------------------
16




4+=
I
200 10.797 0.0116410
5833 0
----------------------------------------------------------------------------------
16



4+=