1. What is Pump Motor Power Calculation?

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

2. How Does the Calculator Work?

The calculator uses the pump power equation:

Where:

• \( P \) — Power (W)
• \( \rho \) — Fluid density (kg/m³)
• \( g \) — Gravity (9.81 m/s²)
• \( Q \) — Flow rate (m³/s)
• \( H \) — Head (m)
• \( \eta \) — Pump efficiency (0 to 1)

Explanation: The equation calculates the hydraulic power required to move the fluid and divides it by the pump efficiency to determine the actual motor power needed.

3. Importance of Power Calculation

Details: Accurate power calculation ensures proper pump selection, prevents motor overload, optimizes energy consumption, and helps in sizing electrical components.

4. Using the Calculator

Tips: Enter fluid density in kg/m³ (water is ~1000 kg/m³), flow rate in m³/s, head in meters, and pump efficiency as a decimal (e.g., 0.85 for 85%). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical pump efficiency value?
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 if I need power in horsepower?
A: Divide watts by 746 (1 HP = 746 W).

Q4: Does this account for system losses?
A: No, this calculates pump power only. Additional system losses (piping, valves) require extra power.

Q5: What's the difference between hydraulic and brake power?
A: Hydraulic power is (ρgQH), while brake power (this calculation) includes efficiency (hydraulic power/η).