1. What is Brushless Motor RPM?

The RPM (Revolutions Per Minute) of a brushless motor is determined by the input voltage, motor's Kv rating, and gear ratio. This calculation helps in selecting the right motor and gearing for your application.

2. How Does the Calculator Work?

The calculator uses the brushless motor RPM equation:

Where:

• \( Voltage \) — Input voltage to the motor (V)
• \( Kv \) — Motor velocity constant (RPM per volt)
• \( Gear\ Ratio \) — Ratio between motor and output (number)

Explanation: The Kv rating indicates how many RPM the motor will turn per volt with no load. The actual RPM under load will be slightly lower due to inefficiencies.

3. Importance of RPM Calculation

Details: Calculating motor RPM is crucial for designing mechanical systems, selecting proper gearing, and ensuring optimal performance in applications like drones, RC vehicles, and industrial machinery.

4. Using the Calculator

Tips: Enter the battery voltage in volts, motor Kv rating in RPM/V, and gear ratio (enter 1 for direct drive). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is Kv rating in brushless motors?
A: Kv is the motor velocity constant representing RPM per volt with no load. Higher Kv means higher speed but lower torque.

Q2: How does gear ratio affect RPM?
A: Higher gear ratios reduce output RPM while increasing torque. Lower ratios increase RPM but decrease torque.

Q3: Why is my actual RPM lower than calculated?
A: Real-world factors like load, efficiency losses, voltage drop, and temperature affect actual RPM. This calculation shows theoretical maximum.

Q4: Can I use this for brushed motors?
A: While the concept is similar, brushed motors have different characteristics and this calculator is specifically for brushless motors.

Q5: How does battery voltage affect RPM?
A: Higher voltage increases RPM proportionally (assuming same Kv). A 3S LiPo (11.1V) will give higher RPM than 2S (7.4V) with the same motor.