1. What is the Electric Motor Torque Formula?

The electric motor torque formula calculates the rotational force produced by an electric motor based on its horsepower and rotational speed. This fundamental engineering equation is essential for motor selection, mechanical design, and performance analysis.

2. How Does the Calculator Work?

The calculator uses the torque formula:

Where:

• \( T \) — Torque (lb-ft)
• \( HP \) — Horsepower (hp)
• \( RPM \) — Rotational speed (rev/min)
• \( 5252 \) — Conversion constant derived from the relationship between horsepower, torque, and rotational speed

Explanation: The constant 5252 comes from the definition of horsepower (1 hp = 550 ft-lb/s) and the conversion from revolutions per minute to radians per second.

3. Importance of Torque Calculation

Details: Accurate torque calculation is crucial for proper motor sizing, ensuring adequate starting and running torque for applications, preventing motor overload, and optimizing energy efficiency in mechanical systems.

4. Using the Calculator

Tips: Enter horsepower in hp and rotational speed in RPM. Both values must be positive numbers greater than zero. The calculator will compute the torque in pound-feet (lb-ft).

5. Frequently Asked Questions (FAQ)

Q1: Why is the constant 5252 used in the formula?
A: The constant 5252 comes from the conversion between horsepower (550 ft-lb/s) and RPM (1 revolution = 2π radians), where 5252 = (550 × 60) ÷ (2π).

Q2: What are typical torque values for electric motors?
A: Torque values vary widely based on motor size and type, ranging from less than 1 lb-ft for small motors to thousands of lb-ft for large industrial motors.

Q3: How does torque relate to motor performance?
A: Torque determines a motor's ability to overcome load resistance. Higher torque means better acceleration and the ability to handle heavier loads.

Q4: Are there different torque measurements?
A: Yes, motors have starting torque, breakdown torque, and full-load torque. This calculator provides the full-load torque at the specified RPM.

Q5: Can this formula be used for all motor types?
A: This formula applies to all rotating machinery where horsepower and RPM are known, including AC/DC motors, engines, and other prime movers.