1. What is the Power Equation?

The power equation (P = V × I) calculates electrical power in watts from voltage and current. It's fundamental for understanding electric motor performance and energy consumption.

2. How Does the Calculator Work?

The calculator uses the power equation:

Where:

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

Explanation: The equation shows that power is directly proportional to both voltage and current in an electrical circuit.

3. Importance of Power Calculation

Details: Accurate power calculation is crucial for selecting proper motor sizes, determining energy efficiency, and ensuring electrical system safety.

4. Using the Calculator

Tips: Enter voltage in volts and current in amps. Both values must be positive numbers for valid calculations.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between input and output power?
A: Input power is what the motor draws from the source (calculated here), while output power is the mechanical power delivered, which is less due to efficiency losses.

Q2: How does power factor affect this calculation?
A: For AC motors, the actual power is P = V × I × PF (power factor). This calculator gives apparent power for DC circuits or when PF is 1.

Q3: What are typical voltage and current ranges for motors?
A: Small motors might use 12V at a few amps, while industrial motors can use 400V+ at hundreds of amps.

Q4: How can I measure voltage and current?
A: Use a multimeter - voltage is measured across terminals, current is measured in series with the circuit.

Q5: What about three-phase motors?
A: Three-phase power calculation is more complex: P = √3 × V × I × PF for balanced systems.