OPTIONAL PROGRAMMING SCREENS
SPECIAL H/Q CURVE PROGRAMMING
The Model 2100 has stored in memory the standard
power functions for most of the common open channel
primary flow devices. These power functions, and the
corresponding primary devices, are found on Page 3-5.
An option selection is available for the user to program
16 points of any head versus flow curve. The following
will describe this procedure. After selecting OPTION, the
ELEMENT FUNCTION screen will appear.
ELEMENT FUNCTION
OPTION
Use the UP or DOWN arrow keys and select the
desired OPTION power function and then press the
ENTER key. The following screen will appear:
OPTIONAL H CURVE
POINT 0 = FFFF
This screen begins with the first point of the Height (H)
portion of the H/Q curve. The input data is required to be in
hexadecimal form. Point 0 is the first point and should be the
first low end point of the curve. The zero height point need
not be input because this is already assumed. Each of the 16
points will represent a percent of the maximum height of the
fluid at the maximum capacity of the primary device.
The hexadecimal value FFFF (65535 decimal) represents
100% of the maximum height. It will be necessary to
determine the decimal value of the desired percent of the
maximum height for each point. Pages 3-10 and 3-11
explain the procedure for converting hexadecimal to decimal
and decimal to hexadecimal. The following is an example of
a 16 point curve with the percent of maximum height to the
corresponding decimal and hexadecimal values.
Point Height %Max Decimal
Hexadecimal
0
0.48"
2
1311
051F
1
0.72"
3
1966
07AE
2
1.20"
5
3277
OCCD
3
1.68"
7
4587
11EB
4
2.16"
9
5898
170A
5
2.88"
12
7864
1EB8
6
3.60"
15
9830
2666
7
4.32"
18
11796
2E14
8
5.04"
21
13762
35C2
9
6.00"
25
16384
4000
A
7.20"
30
19660
4CCC
B
8.40"
35
22937
5999
C
10.80"
45
29491
7333
D
16.08"
67
43908
AB84
E
19.92"
83 54394
D47A
F
24.00"
100
65535
FFFF
Use the RIGHT arrow key to move the cursor under
each digit and use the UP or DOWN arrow keys to
change to the desired value. After all four digits have
been properly set, press the ENTER key. Do this for each
point. After point F, the following screen will appear:
OPTIONAL Q CURVE
POINT 0 = FFFF
This screen is to input the flow (Q) that corresponds to
the same data point for the height just programmed. Use
the same procedure as with the height points only divide
the flow rate at each point (height in primary device) by
the maximum capacity of the primary device (flow at
maximum headrise). Multiply this times 65536 and then
convert to hexadecimal. For example:
If the maximum capacity of the primary device is 3000
GPM (at 24") and the flow at 0.48" (Point 0 from height
curve example) is 20 GPM, then:
20/3000 = .006667 x 65535 = 436.9 = 1B5 Hex
therefore Point 0 = -01B5. Use this procedure for each
flow point.
Use the RIGHT arrow key to move the cursor under each
digit and use the UP or DOWN arrow keys to change to the
desired value. After all four digits have been properly set,
press the ENTER key. Do this for each point. After point F,
the TOTALIZER FUNCTION screen will appear. Return to
Page 3-5 to complete the programming procedure.
To verify the H/Q curve just programmed, go to the
FLOW SIMULATION screen in the Status Mode and
simulate the flow level and check the flow indicated.
Refer to Pages 3-2 and 3-3 for instructions.
A factory H/Q table will be provided by customer
request for special curves.
This completes the procedure for programming an
optional H/Q curve in the Model 2100.
OPTIONAL FLOW RATE UNITS
When the standard flow units are not selected and the
special flow units are programmed with the OPTION
selection, the totalizer must be programmed by a totalizer
word. The following screen will appear after the
ELEMENT FUNCTION screen if an optional flow unit is
programmed in the meter.
TOTALIZER UNIT
UNIT INITIALS=AAA
3-8