Torque Calculator for Electric Motor

Torque Formula:

\[ Torque (Nm) = \frac{Power (kW) \times 9550}{RPM} \]

Torque:

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1. What is Torque in Electric Motors?

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 output affects how quickly a motor can accelerate a load and how much load it can handle.

2. How Does the Calculator Work?

The calculator uses the torque formula:

\[ Torque (Nm) = \frac{Power (kW) \times 9550}{RPM} \]

Where:

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

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

3. Importance of Torque Calculation

Details: Knowing the torque is essential for selecting the right motor for an application, ensuring proper performance, and preventing motor overload or premature failure.

4. Using the Calculator

Tips: Enter the motor power in kW and the rotational speed in RPM. Both values must be positive numbers. The calculator will compute the torque in Newton-meters (Nm).

5. Frequently Asked Questions (FAQ)

Q1: Why is 9550 used in the formula?
A: 9550 is a conversion factor that combines the conversion from kW to watts (×1000) and from radians/second to RPM (×60/2π).

Q2: What's the difference between starting torque and running torque?
A: Starting torque is the torque when the motor begins rotating from standstill, while running torque is the torque during normal operation.

Q3: How does voltage affect torque?
A: For AC induction 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 is a function of torque and RPM. The formula is: HP = (Torque × RPM) / 5252 (for lb-ft units) or HP = (Torque × RPM) / 7121 (for Nm units).

Q5: How can I increase motor torque?
A: Options include using a gear reducer, selecting a motor with higher torque characteristics, or increasing current (within motor limits).