1. What is Pump Motor Power Calculation?

The pump motor power calculation determines the required power for a pump motor to move a specific fluid flow against a given head, considering the fluid's density and the pump's efficiency. This is essential for proper pump selection and energy efficiency.

2. How Does the Calculator Work?

The calculator uses the pump power formula:

Where:

• \( P \) — Power (kW)
• \( Q \) — Flow rate (m³/h)
• \( H \) — Head (m)
• \( \rho \) — Density (kg/m³)
• \( g \) — Gravity (9.81 m/s²)
• \( \eta \) — Pump efficiency (0-1)

Explanation: The formula calculates the hydraulic power needed to move the fluid, then divides by the pump efficiency to get the required motor power.

3. Importance of Proper Power Calculation

Details: Correct power calculation ensures the pump motor is properly sized - not undersized (which would fail to meet requirements) or oversized (which wastes energy and increases costs).

4. Using the Calculator

Tips: Enter flow rate in m³/h, head in meters, density in kg/m³ (1000 for water), and efficiency as a decimal (typically 0.7-0.9 for centrifugal pumps). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical pump efficiency value?
A: Centrifugal pumps typically range from 0.7-0.9 (70-90%). Positive displacement pumps may be higher (0.85-0.95).

Q2: How does viscosity affect the calculation?
A: Higher viscosity fluids require more power. For very viscous fluids, specialized calculations may be needed.

Q3: Should I add a safety factor?
A: Typically, add 10-20% to the calculated power for safety margin and future needs.

Q4: What if my flow is in L/s instead of m³/h?
A: Convert L/s to m³/h by multiplying by 3.6 (1 L/s = 3.6 m³/h).

Q5: Does this account for motor efficiency?
A: No, this calculates pump shaft power. For electrical input power, divide by motor efficiency (typically 0.9-0.95).