Teledyne 4220 = k1HP1+ k2HP2, 270 D.O. module is no longer available from Teledyne Isco

4220 Flow Meter

Section 2 Programming

An Equation is used when you have a non-standard primary device, or want to use different values from those programmed into the look-up tables of the flow meter. Equation uses the standard flow equation:

Q = k1HP1+ k2HP2

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 cal- culate flow in open or closed (non pressurized) gravity-flow situa- tions 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 4220 Flow Meter can calculate flow in round pipes, rectangular, U-shaped, or trapezoidal 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 con- version 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 4220 Flow Meter 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.

2.3.3Step 3 - Adjust Level, Adjust Level, Parameters calibrates the measuring sensors

Parameters	that provide the flow meter with level and other information. In
	this step you set the level that the flow meter measures. 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 provides
	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 you can sense
	such variables in the flow stream as temperature, pH (the acidity
	or alkalinity of a solution) and D.O. (dissolved oxygen) in the flow
	stream. You can have either pH with temperature, D.O. with
	temperature, or temperature alone.

Note

The 270 D.O. module is no longer available from Teledyne

Isco.

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