1. What is Motor Input Power?

Input power (P_in) is the electrical power consumed by a motor to produce the mechanical output power (P_out). The difference between input and output power represents the power lost due to inefficiencies in the motor.

2. How Does the Calculator Work?

The calculator uses the input power formula:

Where:

• \( P_{in} \) — Input power (watts)
• \( P_{out} \) — Output power (watts)
• \( \eta \) — Motor efficiency (decimal between 0 and 1)

Explanation: The formula shows that input power equals output power divided by the motor's efficiency. Higher efficiency means less input power is needed for the same output.

3. Importance of Input Power Calculation

Details: Calculating input power helps in sizing electrical components, estimating energy consumption, and evaluating motor performance. It's essential for energy efficiency assessments and cost calculations.

4. Using the Calculator

Tips: Enter output power in watts and efficiency as a decimal (e.g., 0.85 for 85%). Efficiency must be between 0 and 1 (typically 0.7-0.95 for electric motors).

5. Frequently Asked Questions (FAQ)

Q1: What is typical motor efficiency?
A: Small motors might be 70-85% efficient, while large industrial motors can reach 95% efficiency or higher.

Q2: How does efficiency affect input power?
A: A less efficient motor requires more input power to produce the same output. For example, at 50% efficiency, input power is double the output power.

Q3: Can I use this for different power units?
A: Yes, but all values must use consistent units (e.g., all in watts or all in horsepower).

Q4: Why is my calculated input power higher than output?
A: This is normal - input power is always greater than or equal to output power due to inherent energy losses in the motor.

Q5: How can I improve motor efficiency?
A: Use properly sized motors, maintain them regularly, consider high-efficiency models, and ensure optimal operating conditions.