Emerson Rosemount 3490 Series, Справочное руководство

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Setting P116 (or P126) to the maximum volume of the vessel
Parameter P116 (or P126) must be programmed with the volume of the contents in a full
vessel in the units chosen (P200, P201, P202, or P203, as applicable to the transmitter
input channel). The level measurement value, which is now in the range 0.0 to 1.0, is
multiplied by the P116 (or P126) value to get the volume of the contents. The resulting
volume is then passed to the optional low volume cut-off action.
Note
Rosemount 3491/3493:
P116 is in the menu
SETUP
→
[CONTROLLER]
→
INPUT CHANNEL
→
Ch1 Post Scale .
P20x parameters are in the menu SETUP
→
[CONTROLLER]
→
DISPLAY .
Note
Rosemount 3492:
P116
is in this menu
SETUP
→
[CONTROLLER]
→
PV CALCULATION
→
CHANNEL 1
→
Ch1
Post Scale .
P126 is in this menu SETUP
→
[CONTROLLER]
→
PV CALCULATION
→
CHANNEL 2
→
Ch2
Post Scale
.
P20x parameters are in the menu SETUP
→
[CONTROLLER]
→
DISPLAY .
Set-up flow calculations for non-linear/non-uniform open
channel profiles (advanced users)
The Rosemount 3490 Series Control Unit can use level measurements to calculate flow in
open channels, which can then be totalized. The control unit has a library of popular non-
linear profiles for flow:
• Flume 3/2
• V-Notch 5/2
• Manning formula
Figure 4-17 shows a typical open channel flow structure.
Reference Manual Getting started
00809-0100-4841 January 2021
Emerson.com/Rosemount 75