Frequency to RPM Calculator

RPM Formula:

\[ RPM = Frequency \times 60 \div (Poles \div 2) \]

RPM:

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1. What is Frequency to RPM Conversion?

The Frequency to RPM conversion calculates the rotational speed of an AC motor in revolutions per minute (RPM) based on the electrical frequency and number of motor poles. This is essential for understanding motor performance and synchronization.

2. How Does the Calculator Work?

The calculator uses the RPM formula:

\[ RPM = Frequency \times 60 \div (Poles \div 2) \]

Where:

\( Frequency \) — Electrical frequency in Hertz (Hz)
\( Poles \) — Number of magnetic poles in the motor
\( 60 \) — Conversion factor from seconds to minutes
\( Poles \div 2 \) — Number of pole pairs

Explanation: The formula calculates the synchronous speed of an AC motor, where the rotational speed is determined by the frequency of the power supply and the motor's pole configuration.

3. Importance of RPM Calculation

Details: Accurate RPM calculation is crucial for motor selection, system design, speed control applications, and ensuring proper motor operation within specified parameters.

4. Using the Calculator

Tips: Enter frequency in Hz and number of poles (must be even number, minimum 2). Common frequencies are 50Hz or 60Hz depending on regional power standards.

5. Frequently Asked Questions (FAQ)

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

Q2: Why must poles be an even number?
A: Magnetic poles in motors always occur in pairs (north and south), so the total number must be even.

Q3: What are common pole configurations?
A: Common configurations include 2-pole (3600 RPM at 60Hz), 4-pole (1800 RPM at 60Hz), 6-pole (1200 RPM at 60Hz), and 8-pole (900 RPM at 60Hz).

Q4: How does frequency affect motor speed?
A: Motor speed is directly proportional to frequency. Doubling the frequency doubles the speed, assuming constant pole count.

Q5: What is the difference between synchronous and actual RPM?
A: Actual RPM is slightly less than synchronous RPM due to slip, which allows the motor to produce torque. Slip typically ranges from 1-5% for induction motors.