What this tool does
Screens both flow and pressure margins so a flow-only head count is not mistaken for a feasible zone.
When to use it
Use after measuring available flow and dynamic pressure at comparable conditions.
Inputs and supported units
Each labelled field explains the quantity it expects. Unit-system changes convert existing numeric entries once and keep calculations on a single SI internal basis. Supported shared units include L/min and GPM, metres and feet, kPa and psi, millimetres and inches, kW and hp, and °C and °F as relevant.
Calculation or decision method
How to interpret the result
Read the primary result with the supporting breakdown and warning. A plausible number is not evidence that every input, operating case or design constraint has been included.
Worked example
100 L/min with 10% reserve and 12 L/min/head yields seven whole heads and 6 L/min unused.
Assumptions
Entered measurements represent the same operating condition. Calculations use unrounded SI values and convert only for display.
Limitations
This is a preliminary planning screen, not a design approval, irrigation audit, pump curve analysis or distribution-uniformity test.
Sources
- USDA NRCS — Irrigation Guide, Chapter 6
- Hunter Industries — Irrigation Technical Manual
- Rain Bird — Irrigation Design Manual