1. What is Shaft Power?

Shaft power is the actual mechanical power delivered by an electric motor to the pump shaft. It accounts for the motor's efficiency in converting electrical power to mechanical power.

2. How Does the Calculator Work?

The calculator uses the shaft power equation:

Where:

• \( P_{shaft} \) — Shaft power (watts)
• \( P_{motor} \) — Motor input power (watts)
• \( Efficiency \) — Motor efficiency (decimal between 0 and 1)

Explanation: The equation calculates the actual mechanical power available at the pump shaft by accounting for energy losses in the motor.

3. Importance of Shaft Power Calculation

Details: Accurate shaft power calculation is crucial for proper pump selection, system design, and energy efficiency analysis in fluid systems.

4. Using the Calculator

Tips: Enter motor power in watts and efficiency as a decimal (e.g., 0.85 for 85%). Efficiency must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is typical motor efficiency?
A: Standard motors typically have 80-95% efficiency, with higher efficiency in larger motors and premium efficiency models.

Q2: How does this relate to pump hydraulic power?
A: Shaft power is further reduced by pump efficiency to get hydraulic power delivered to the fluid.

Q3: Should I use nameplate or measured motor power?
A: For accurate results, use actual measured motor power if available, otherwise use nameplate rating.

Q4: What are common units for shaft power?
A: While watts are standard, horsepower (1 hp = 745.7 watts) is also commonly used in some industries.

Q5: Does this account for variable speed drives?
A: No, this is for direct motor operation. VFDs may affect both motor power and efficiency.