4210 Flow Meter
Section 2 Programming
2-7
...where Q equals flow rate; k1 and k2 are constants; H is level
(or head), and P1 and P2 are the powers to which the two H
terms are raised. (Your equation may not have the second term,
in which case you would enter 0 for the second constant, k2.)
Most common primary devices are supported in the flow meter's
software, so generally you will not need this option. But it is
available for those needing to enter their own values, or for those
who have a nonstandard primary device for which an equation
can correlate level and flow.
MANNING Flow Conversion – uses the Manning formula to
calculate flow in open or closed (non pressurized) gravity-flow sit-
uations based on slope, diameter, and roughness of the pipe. The
Manning formula is named for its developer, Robert Manning, a
19th-century Irish civil engineer. There is no primary measuring
device as such. Instead the pipe, with considerations for its slope
and internal roughness, serves as the primary device. The 4210
can calculate flow in round pipes, rectangular, U-shaped, or trap-
ezoidal channels based on this formula.
Data Point Flow Conversion (DATA POINTS) – calculates
flow based on a set of user-entered data points for a flow stream.
Data consist of correlated level and flow measurements for the
stream. Like the Equation method of flow conversion, this flow
conversion is most commonly used where the primary measuring
device is nonstandard, but where tables of level and flow rate
data are available from the device manufacturer. The 4210 has
space for four sets of data with as many as fifty points per set.
The flow meter then calculates flow from these data tables using
a three-point interpolation.
2.4.3 Step 3 - Adjust Level,
Parameters
ADJUST LEVEL, PARAMETERS calibrates the measuring
sensors that provide the flow meter with level and other infor-
mation. In this step you set the level that the flow meter mea-
sures. First you measure, as accurately as possible, the level in
the flow stream. Then you enter this value with the numeric
keys. Accuracy is important. Remember that measured level pro-
vides the basis for calculated flow in the flow meter.
The flow meter also has an input port for measurements other
than level. This is the Parameter Port. Here the meter can sense
such variables in the flow stream as temperature, pH (the acidity
or alkalinity of a solution) and D.O. (dissolved oxygen). You can
have either pH with temperature, D.O. with temperature, or
temperature alone. The port is not dedicated to a particular
sensor, except through programming. For example, you can
change from a pH probe to a D.O. sensor if you change the pro-
gramming. Selection of one parameter will keep the other from
showing up on the menus. Note, however, that it is possible to
measure several different stream conditions (including pH and
D.O.) at the same time with the YSI 600 Sonde.
The YSI 600 Sonde – The YSI 600 Sonde is a multi-purpose,
water quality measurement device. It is intended for use in
research, assessment, and regulatory compliance. The sonde
attaches to the modified RAIN GAUGE connector on the 4210.
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