1. What is the Pump Power Formula?

Definition: This calculator determines the horsepower required to pump water based on flow rate, total head, and pump efficiency.

Purpose: It helps engineers and technicians properly size pumps for water systems to ensure adequate performance.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Horsepower required
• \( Q \) — Flow rate (gallons per minute, GPM)
• \( H \) — Total head (feet)
• \( \eta \) — Pump efficiency (0-1)
• 8.34 — Weight of water (lbs/gallon)
• 3960 — Conversion factor (ft-lbs/min to HP)

Explanation: The formula calculates the power needed to move water against gravity and system resistance.

3. Importance of Pump Power Calculation

Details: Proper pump sizing ensures energy efficiency, prevents overloading motors, and delivers required flow rates.

4. Using the Calculator

Tips: Enter flow rate in GPM, total head in feet, and pump efficiency (default 0.85 for 85%). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is total head (H)?
A: Total head is the sum of static head (vertical distance) and friction head (pipe resistance).

Q2: Typical pump efficiency values?
A: Centrifugal pumps typically range 70-85%, while positive displacement pumps can reach 90%.

Q3: How do I find my system's flow rate?
A: Measure with flow meters or calculate based on pipe size and velocity.

Q4: Should I add a safety factor?
A: Yes, consider adding 10-20% to the calculated HP for system variations.

Q5: What about motor efficiency?
A: This calculates hydraulic HP. For brake HP, divide by motor efficiency.