1. What is Pump Motor Power Calculation?

The pump motor power calculation determines the required power for a pump to move a fluid at a specified flow rate against a given head, accounting for the fluid's density and the pump's efficiency.

2. How Does the Calculator Work?

The calculator uses the pump power equation:

Where:

• \( P \) — Motor power (watts)
• \( Q \) — Flow rate (m³/s)
• \( \rho \) — Fluid density (kg/m³)
• \( g \) — Gravitational acceleration (9.8 m/s²)
• \( h \) — Head (meters)
• Efficiency — Pump efficiency (decimal 0-1)

Explanation: The equation calculates the power required to move a fluid against gravity and system resistance, adjusted for pump efficiency.

3. Importance of Motor Power Calculation

Details: Proper motor sizing ensures efficient pump operation, prevents underpowering (which can cause failure) and overpowering (which wastes energy and increases costs).

4. Using the Calculator

Tips: Enter flow rate in m³/s, density in kg/m³, head in meters, and efficiency as a decimal (e.g., 0.85 for 85%). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is typical pump efficiency?
A: Centrifugal pumps typically range from 40-85% efficiency, with higher efficiency in larger, well-designed pumps.

Q2: How do I convert flow rate from L/s to m³/s?
A: Divide L/s by 1000 (1 m³/s = 1000 L/s).

Q3: What density should I use for water?
A: Pure water at 4°C is 1000 kg/m³. For other temperatures, adjust accordingly (about 998 kg/m³ at 20°C).

Q4: Should I add a safety factor?
A: Yes, it's common to add 10-20% to the calculated power to account for system losses and future demands.

Q5: How does viscosity affect the calculation?
A: High viscosity fluids require more power and may reduce pump efficiency. Special calculations are needed for non-Newtonian fluids.