1. What is Electric Motor Torque?

Torque is the rotational force produced by an electric motor. It's a crucial parameter that determines the motor's ability to perform work and overcome resistance. The torque of an electric motor depends on its power and rotational speed (RPM).

2. How Does the Calculator Work?

The calculator uses the torque formula:

Where:

• \( Power \) — Motor power in kilowatts (kW)
• \( RPM \) — Rotational speed in revolutions per minute
• \( 9550 \) — Conversion factor combining unit conversions and constants

Explanation: The formula shows that torque is inversely proportional to RPM when power is constant. Higher RPM means lower torque, and vice versa.

3. Importance of Torque Calculation

Details: Knowing a motor's torque is essential for proper motor selection, ensuring it can handle the required mechanical load. It's critical in applications like conveyor systems, pumps, and electric vehicles.

4. Using the Calculator

Tips: Enter motor power in kW and rotational speed in RPM. Both values must be positive numbers (power > 0, RPM > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why is 9550 used in the formula?
A: 9550 combines the conversion factors between kW, Nm, and RPM. It's derived from (60,000)/(2π) where 60,000 converts minutes to seconds and kW to watts, and 2π converts radians to revolutions.

Q2: What's the difference between starting torque and running torque?
A: Starting torque is the torque when the motor begins turning from rest (usually higher), while running torque is during normal operation.

Q3: How does voltage affect motor torque?
A: For AC induction motors, torque is proportional to the square of the voltage. Reduced voltage significantly decreases available torque.

Q4: What is the relationship between torque and efficiency?
A: Motors are typically most efficient at around 75-80% of their rated torque. Both very low and very high torque operation can reduce efficiency.

Q5: Can this formula be used for all motor types?
A: This formula works for most electric motors when operating at steady state. Special cases like servo motors or motors with variable frequency drives may require additional considerations.