Rosemount 3491 - Page 62

Reference Manual
00809-0100-4841, Rev. AA
May 2007
Rosemount 3490 Series
4-30
Table 4-8. Pre-programmed
flow calculation factors (flumes)
NOTE:
When a flume is selected from this list, the 3490 Series Control Unit also
populates parameters P401 and P401 (4-20mA output), P530 (Totaliser
factor), and P531 (Totaliser units of m
3
or galx100).
Standard flow calculations of form Q=k x h
Pwr
When P113=“Flume***”, the flow calculation is of the standard flow law form
of Q=k x h
Pwr
. This option is applicable when the flow structure does not
match one of the pre-programmed standard structures.
Enter your pwr, k and mul factors into parameter P115. Then, use P200 to
select the display units. Finally, use P116 to get the correctly scaled MCU PV
for the chosen display units.
Profile (P113)
(1)
(1) After selecting a flat or parabolic flume using P113, parameter P115 (Pwr, k, and mul factors) and
parameter P116 are populated for measuring flow in metric units of cubic metres per hour (m
3
/hour).
For flow measurement in alternative units (with automatic scaling of MCU PV), use the Duty Wizard.
(Menu: SETUP / [CONTROL UNIT /] DUTY(Mode) / Duty Wizard)
The choice of units offered depends on whether the transmitter is measuring in metric or imperial units.
k (P115) Pwr (P115) Mul (P115) P116
Flume Flat 1 0.1347877 1.5 0.01 3600.0
Flume Flat 2 0.1782664 1.5 0.01 3600.0
Flume Flat 3 0.3134177 1.5 0.01 3600.0
Flume Flat 4 0.5417157 1.5 0.01 3600.0
Flume Flat 5 0.8111058 1.5 0.01 3600.0
Flume Flat I 0.1322 1.5 0.01 3600.0
Flume Flat II 0.1777 1.5 0.01 3600.0
Flume Flat III 0.21758 1.5 0.01 3600.0
Flume Flat III bis
0.32835
1.5 0.01 3600.0
Flume Flat III ter 0.272 1.5 0.01 3600.0
Flume Flat IV 0.3521726 1.5 0.01 3600.0
Flume Flat V 0.442932 1.5 0.01 3600.0
Flume Flat V bis 0.4005 1.5 0.01 3600.0
Flume Flat VI 0.4990569 1.5 0.01 3600.0
Flume Flat VII 0.6237 1.5 0.01 3600.0
Flume Flat VIII 0.88116 1.5 0.01 3600.0
Flume Flt VIII bis 0.798 1.5 0.01 3600.0
Flume Flat IX 1.065186 1.5 0.01 3600.0
Flume Flat IX bis 0.8148 1.5 0.01 3600.0
Flume Flat X 1.3222761 1.5 0.01 3600.0
Flume Flat X bis 1.609 1.5 0.01 3600.0
Flume Flat X ter 1.064884 1.5 0.01 3600.0
Flume Flat XI 1.65099 1.5 0.01 3600.0
Flume Para 1 0.39885 2.3 0.01 3600.0
Flume Para 2 0.44187 2.3 0.01 3600.0
Flume Para 3 0.46362 2.2 0.01 3600.0
Flume Para 4 0.54419 2.2 0.01 3600.0
Flume Para 5 0.61851 2.1 0.01 3600.0
Flume Para 6 0.71726 2.1 0.01 3600.0
Flume Para 7 0.77152 2.1 0.01 3600.0
Flume*** (User) (User) (User) 3600.0