1. What is the Power Formula?

The power formula (P = V × I × PF) calculates electrical power in watts from voltage, current, and power factor. It's fundamental in electrical engineering for determining power consumption in AC and DC circuits.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( PF \) — Power factor (unitless, 0 to 1)

Explanation: For DC circuits, power factor is 1. For AC circuits, power factor accounts for phase difference between voltage and current.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for circuit design, energy consumption analysis, electrical safety, and proper sizing of components and wiring.

4. Using the Calculator

Tips: Enter voltage in volts, current in amperes, and power factor (1 for DC circuits). All values must be valid (voltage > 0, current > 0, 0 ≤ PF ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing efficiency of power usage in AC systems. It ranges from 0 to 1.

Q2: When is power factor not 1?
A: In AC circuits with inductive or capacitive loads (motors, transformers), where current and voltage waveforms are out of phase.

Q3: How does this differ from apparent power?
A: Apparent power (VA) is V × I, while real power (W) is V × I × PF. This calculator gives real power.

Q4: Can I use this for three-phase systems?
A: For balanced three-phase systems, multiply result by √3 (about 1.732). For unbalanced systems, calculate each phase separately.

Q5: Why is my calculated power lower than expected?
A: This could indicate a low power factor, which means not all current is doing useful work (common with inductive loads).