Pumps Africa & Tools
VSD Pump Duty Scaler (Affinity Laws) Variable Speed Duty Calculator
Enter duty point(s) at base Hz, scale to new Hz (Q/H/P), efficiency auto-calculated, and print a clean A4 report.
Affinity laws: Q ∝ N, H ∝ N², P ∝ N³ (same impeller Ø). Q units assumed **m³/h**.
Scaling summary
Waiting for inputs…
Original curve (base Hz) Scaled curve (new Hz)
Input duties (Base Hz)
| # | Flow Q (m³/h) | Head H (m) | Power P (kW) | Eff. (%) |
|---|
Output duties (Scaled to New Hz)
| # | Flow Q′ (m³/h) | Head H′ (m) | Power P′ (kW) | Eff.′ (%) |
|---|
“Download PDF” builds a clean A4 report: curve on its own page (black & bold; grey grid), data on other page(s), and no Elementor outlines.
Pumps Africa & Tools — VSD Pump Duty Report
Input duties (Base Hz)
| # | Flow Q (m³/h) | Head H (m) | Power P (kW) | Eff. (%) |
|---|
Output duties (Scaled to New Hz)
| # | Flow Q′ (m³/h) | Head H′ (m) | Power P′ (kW) | Eff.′ (%) |
|---|