Convert Hertz to RPM Calculator

RPM Formula:

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

Motor RPM:

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1. What is Hertz to RPM Conversion?

The conversion from Hertz (Hz) to RPM (Revolutions Per Minute) calculates the rotational speed of an AC motor based on its electrical frequency and number of magnetic poles. This is essential for motor control and industrial applications.

2. How Does the Calculator Work?

The calculator uses the RPM formula:

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

Where:

\( Hz \) — Electrical frequency in hertz
\( Poles \) — 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 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, speed control applications, industrial machinery design, and ensuring proper operation of motor-driven equipment.

4. Using the Calculator

Tips: Enter frequency in Hz and number of poles. Common frequencies are 50 Hz or 60 Hz depending on regional power standards. Pole counts are typically even numbers (2, 4, 6, 8, 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 motor speed is slightly less due to slip.

Q2: Why divide poles by 2 in the formula?
A: Because each complete magnetic cycle requires two poles (north and south), so we use pole pairs in the calculation.

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

Q4: Does this work for all motor types?
A: This formula calculates synchronous speed for AC induction and synchronous motors. DC motors and variable frequency drives have different speed characteristics.

Q5: What is motor slip?
A: Slip is the difference between synchronous speed and actual rotor speed, typically 1-5% for induction motors under load.