3 Phase Motor Torque Calculator

3 Phase Motor Torque Formula:

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

Torque:

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1. What is 3 Phase Motor Torque?

Torque is the rotational force produced by a 3-phase motor. It's a crucial parameter that determines the motor's ability to perform work and overcome mechanical resistance. The torque varies with motor speed (RPM) and input power.

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)
\( RPM \) — Motor speed in revolutions per minute
9550 — Conversion factor combining unit conversions and constants

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 proper motor selection, ensuring it can handle the mechanical load requirements. It's also critical for system design, safety considerations, and energy efficiency.

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 combines the conversion factors from kW to watts (1000), minutes to seconds (60), and radians to revolutions (2π) into one constant for simplification.

Q2: What is the relationship between power, torque, and RPM?
A: Power is proportional to both torque and RPM. For a given power, torque decreases as RPM increases, and vice versa.

Q3: What are typical torque values for industrial motors?
A: Torque varies widely based on motor size and application, from fractions of Nm for small motors to thousands of Nm for large industrial motors.

Q4: How does motor efficiency affect torque?
A: The formula calculates theoretical torque. Actual torque may be lower due to efficiency losses (heat, friction, etc.).

Q5: Can this calculator be used for single-phase motors?
A: The basic torque formula applies, but single-phase motors often have different performance characteristics and lower starting torque.