1. What is the DC Motor Power Formula?

The DC Motor Power Formula (P = V × I) calculates the electrical power input to a DC motor, where P is power in watts, V is voltage in volts, and I is current in amps. This represents the electrical energy consumed by the motor per second.

2. How Does the Calculator Work?

The calculator uses the DC power equation:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( I \) — Current in amperes (A)

Explanation: The formula shows that power is directly proportional to both voltage and current. Doubling either voltage or current will double the power.

3. Importance of Power Calculation

Details: Calculating motor power is essential for selecting appropriate power supplies, determining energy consumption, sizing circuit components, and evaluating motor efficiency.

4. Using the Calculator

Tips: Enter voltage in volts and current in amps. Both values must be positive numbers. The calculator will compute the electrical power in watts.

5. Frequently Asked Questions (FAQ)

Q1: Is this the input or output power of the motor?
A: This calculates the electrical input power. Mechanical output power would be less due to efficiency losses.

Q2: How does this relate to motor torque?
A: Mechanical power (output) relates to torque and RPM: P = τ × ω, where τ is torque and ω is angular velocity.

Q3: Can I use this for AC motors?
A: For AC motors, you need to consider power factor: P = V × I × PF for single-phase, or P = √3 × V × I × PF for three-phase.

Q4: What's typical power range for small DC motors?
A: Small hobby motors might be 5-100W, while larger industrial DC motors can be several kilowatts.

Q5: How does voltage affect motor speed?
A: In DC motors, speed is roughly proportional to voltage (minus voltage drops), while torque is proportional to current.