Slip of Induction Motor Calculator

Compute synchronous speed and slip (%) from supply frequency, pole count and rotor speed.


Slip of Induction Motor

Slip is a defining characteristic of induction motors and plays a crucial role in their operation. Unlike synchronous motors, induction motors must operate at a speed slightly lower than the synchronous speed to produce torque. This difference in speed is known as slip. The Slip of Induction Motor Calculator helps determine motor slip using supply frequency, number of poles, and rotor speed.


What Is Slip in an Induction Motor?

Slip is the relative difference between the synchronous speed of the rotating magnetic field and the actual rotor speed.
It is expressed as a:
• Decimal
• Percentage
Slip is necessary for inducing rotor current and generating electromagnetic torque.


Slip Formula

Slip is calculated using:

s = (Nₛ − Nᵣ) / Nₛ
Where:
• Nₛ = Synchronous speed (RPM)
• Nᵣ = Rotor speed (RPM)

Slip percentage:
Slip (%) = s × 100


Synchronous Speed Formula

Synchronous speed depends on supply frequency and number of poles:
Nₛ = (120 × f) / P
Where:
• f = Supply frequency (Hz)
• P = Number of poles


How to Use the Slip Calculator

1. Enter supply frequency
2. Enter number of motor poles
3. Enter measured rotor speed
4. Click Calculate
The calculator outputs synchronous speed and slip percentage.


Importance of Slip in Motor Performance

Slip affects:
• Torque production
• Rotor current
• Efficiency
• Heat generation
High slip leads to increased losses and reduced efficiency, while very low slip limits torque.

Applications of Slip Calculation

• Motor performance analysis
• Fault diagnosis
• Speed control systems
• Industrial motor testing

Slip is fundamental to induction motor operation. This calculator simplifies slip determination and supports accurate motor analysis and troubleshooting.



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