Motor Torque Calculator
Calculate torque (Nm) from power and RPM. Formula: T = (P × 60) / (2π × n)
Motor Torque Calculator
Motor torque is one of the most important parameters in electrical machines and drives. It represents the rotational force produced by a motor and determines the motor’s ability to drive mechanical loads such as pumps, conveyors, compressors, and fans. Understanding motor torque is essential for correct motor selection, performance analysis, and mechanical system design.
This Motor Torque Calculator helps you accurately calculate motor torque using power and rotational speed, eliminating manual calculation errors and saving valuable design time.
What Is Motor Torque?
Torque is the rotational force that causes an object to rotate about an axis. In electric motors, torque is produced when current interacts with a magnetic field inside the motor.
Torque is typically measured in:
• Newton-meters (N·m)
• Pound-feet (lb·ft)
Higher torque means greater ability to overcome load resistance and start or accelerate a mechanical system.
Relationship Between Power, Speed, and Torque
Motor torque is directly related to mechanical power and speed. This relationship is fundamental in electrical engineering and mechanical design.
The basic equation is:
T = P / ω
Where:
• T = Torque (N·m)
• P = Mechanical power (W)
• ω = Angular speed (rad/s)
For practical calculations using RPM and kilowatts, the formula becomes:
T (N·m) = (P (kW) × 1000 × 60) / (2π × n (RPM))
This is the formula used in the motor torque calculator.
How to Use the Motor Torque Calculator
1. Enter the motor’s output power in kilowatts (kW)
2. Enter the motor speed in revolutions per minute (RPM)
3. Click Calculate
4. The calculator instantly provides the torque in Newton-meters
This method is widely used for AC motors, DC motors, and industrial drive systems.
Importance of Torque in Motor Selection
Torque plays a key role in:
• Starting heavy loads
• Overcoming friction and inertia
• Maintaining constant speed under load
• Preventing motor stalling
Motors with insufficient torque may fail to start or overheat under load, leading to reduced lifespan and inefficiency.
Applications of Motor Torque Calculation
• Selecting motors for pumps, fans, and compressors
• Conveyor and elevator design
• Industrial automation systems
• Electric vehicle drivetrains
• Mechanical power transmission systems
Common Mistakes in Torque Calculation
• Using electrical input power instead of mechanical output power
• Ignoring efficiency losses
• Mixing RPM and rad/s incorrectly
• Forgetting load variations
Motor torque calculation is a fundamental engineering task that ensures safe, efficient, and reliable motor operation. This Motor Torque Calculator provides a fast and accurate method to determine torque, supporting better motor selection and system design.