Torque Calculation Formula for Motor

Motor Torque Formula:

\[ T = \frac{P \times 9550}{N} \]

Torque (T):

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1. What is Motor Torque?

Torque is a 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 calculation helps in selecting the right motor for specific applications.

2. How Does the Calculator Work?

The calculator uses the motor torque formula:

\[ T = \frac{P \times 9550}{N} \]

Where:

\( T \) — Torque in Newton-meters (Nm)
\( P \) — Power in kilowatts (kW)
\( N \) — Rotational speed in revolutions per minute (RPM)
9550 — Conversion factor combining unit conversions and constants

Explanation: The formula relates the motor's power output to its rotational speed, showing that torque decreases as speed increases for a given power.

3. Importance of Torque Calculation

Details: Accurate torque calculation is essential for proper motor selection, ensuring the motor can handle the required load without stalling or overheating. It's critical in applications like conveyor systems, pumps, and machine tools.

4. Using the Calculator

Tips: Enter power in kW and speed in RPM. Both values must be positive numbers. The calculator will compute the torque in Nm.

5. Frequently Asked Questions (FAQ)

Q1: Why is 9550 used in the formula?
A: 9550 combines the conversion factors between kW to W, RPM to rad/s, and accounts for the 2π radians in one revolution.

Q2: What's the difference between starting torque and running torque?
A: Starting torque is the torque when the motor begins to rotate, often higher than running torque which is the torque during continuous operation.

Q3: How does voltage affect motor torque?
A: For AC motors, torque is proportional to the square of the voltage. Lower voltage results in significantly reduced torque.

Q4: What is the relationship between torque and horsepower?
A: Horsepower = (Torque × RPM) / 5252 (when torque is in lb-ft). They're related through rotational speed.

Q5: How do I account for efficiency in torque calculations?
A: For more accurate results, use the motor's actual output power (input power × efficiency) rather than rated power.