1. What is Motor RPM?

RPM (Revolutions Per Minute) is a measure of how many complete rotations a motor makes in one minute. It's a crucial parameter for motor selection and application in various industries.

2. How Does the Calculator Work?

The calculator uses the RPM formula:

Where:

• \( Frequency \) — AC power supply frequency in Hertz (Hz)
• \( Poles \) — Number of magnetic poles in the motor (always an even number)
• 120 — Constant factor (60 seconds × 2 for alternating current)

Explanation: The synchronous speed of an AC motor depends on the frequency of the power supply and the number of poles in the motor winding.

3. Importance of RPM Calculation

Details: Knowing a motor's RPM is essential for proper equipment selection, ensuring compatibility with driven machinery, and achieving desired operational speeds.

4. Using the Calculator

Tips: Enter the power supply frequency in Hz and the number of poles in the motor. The number of poles must be an even number (2, 4, 6, etc.).

5. Frequently Asked Questions (FAQ)

Q1: What is synchronous speed?
A: Synchronous speed is the theoretical speed at which the motor's magnetic field rotates. Actual speed is slightly less due to slip.

Q2: Why must poles be even numbers?
A: AC motors require pairs of north and south poles, so the number of poles is always even (2, 4, 6, etc.).

Q3: What's the difference between RPM and synchronous speed?
A: Synchronous speed is theoretical, while actual RPM is slightly lower due to slip in induction motors.

Q4: How does voltage affect RPM?
A: Voltage doesn't directly affect synchronous RPM, but insufficient voltage may prevent the motor from reaching its rated speed.

Q5: Can this be used for DC motors?
A: No, DC motor speed depends on voltage and load, not on poles and frequency.