1. What is Motor Power Calculation for Pumps?

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

2. How Does the Calculator Work?

The calculator uses the motor power formula:

Where:

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

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

3. Importance of Motor Power Calculation

Details: Accurate power calculation ensures proper pump selection, prevents motor overload, optimizes energy consumption, and helps design efficient pumping systems.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What is typical pump efficiency?
A: Centrifugal pumps typically have 70-90% efficiency, while positive displacement pumps can reach 90-95%. Efficiency depends on pump type, size, and operating conditions.

Q2: How does viscosity affect power requirements?
A: Higher viscosity fluids require more power. For viscous fluids, additional calculations may be needed to account for friction losses.

Q3: Should I add a safety factor?
A: Yes, it's common practice to add 10-20% safety margin to the calculated power to account for system variations and future requirements.

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: How does system curve affect power requirements?
A: The operating point where pump curve intersects system curve determines actual flow and head, which affects power consumption.