Synchronous Speed Calculator
Compute synchronous speed Ns = 120 × f / P (RPM).
Synchronous Speed Calculator
Synchronous speed is the speed at which the rotating magnetic field of an AC machine revolves. It is a critical parameter in the analysis of induction motors, synchronous motors, and alternators.
The Synchronous Speed Calculator provides a quick and accurate method to calculate synchronous speed using frequency and pole count.
What Is Synchronous Speed?
Synchronous speed is the theoretical speed of the magnetic field in an AC machine. It depends only on:
• Supply frequency
• Number of poles
It does not depend on load or motor type.
Synchronous Speed Formula
Nₛ = (120 × f) / P
Where:
• Nₛ = Synchronous speed (RPM)
• f = Supply frequency (Hz)
• P = Number of poles
How to Use the Synchronous Speed Calculator
1. Enter the supply frequency
2. Enter the number of poles
3. Click Calculate
The calculator returns synchronous speed in RPM.
Relationship with Induction Motors
Induction motors always operate slightly below synchronous speed due to slip. Synchronous motors, however, run exactly at synchronous speed once synchronized.
Practical Importance
Synchronous speed is used in:
• Motor speed classification
• Slip calculation
• Motor selection
• Power system analysis
Synchronous speed is a foundational concept in AC machine theory. This calculator allows quick evaluation and supports accurate electrical machine analysis.