Mace HydroMace 3000 Product Manual page 34

21.3.4 Edit "Flowrate (Velocity)" channel type
pipe diameter
If the "Velocity channel" source is an I/O card then the "Pipe diameter"
(cross-sectional area if a non-circular pipe) is entered here.
If the "Flowrate" channel is configured for "Conduit using depth" then the
"Pipe diameter" field will not appear.
Siltation depth
This parameter can be used to correct the calculated flow rate if a known
amount of silt is inside the pipe.
The depth of silt will be subtracted from the area calculation in order to
calculate the corrected flow rate.
21.3.4.2 Flowrate: Using Polynomial
When the stream flow is in an open channel (non-circular), the user must
determine the cross-sectional area and relate it to depth via a polynomial
equation. MACE Flo-series instruments can use 5th order polynomial
equations.
Channel name
Decimal places
Measured channels
Flowrate units
Polynomial
coefficients
Siltation depth
58 SeCtion b SoFtware Manual
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Channel name
This is the name given to the channel by the user when setup.
Decimal places
The user can set the number of decimal places (0, 1, 2, 3) using the drop down
list box. These decimal places will be shown in both the data file and the LCD.
Display channel
If this check box is ticked then this channel will be displayed on the HM 3000
LCD.
Log channel
If this check box is ticked then this channel will be logged in the data file.
Measured channels
"Flowrate" is a derived channel type. These fields define from which measured
channels flowrate is being calculated.
Flowrate units
Select the units and the timebase from the drop down list boxes. This sets the
units on the logged value.
polynomial coefficients
Display channel
The polynomial coefficients listed in FloCom
Log channel
equation:
Cross-Sectional Area = A + B*X +C*X2 + D*X3 + E*X4 + F*X5
Where X = depth of stream
The coefficients are listed in order A, B, C, D, E, F.
Polynomial coefficients
dialogue box
RetuRn to toC RetuRn to toC
NOte: this name will also show on the hM 3000 LCD screen if the
Display channel check box is ticked
+
are related to the following
Depth limit
Import parameters
from FloCalc
MaCe HydRoMaCe 3000 Product Manual 59