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 and circuit design.

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 or AC circuits with purely resistive loads, the power factor is 1. For AC circuits with reactive components, the power factor is less than 1.

3. Importance of Power Calculation

Details: Accurate power calculation is crucial for circuit design, electrical safety, energy efficiency, and proper sizing of electrical components.

4. Using the Calculator

Tips: Enter voltage in volts, current in amps, and power factor (1 for DC or resistive AC 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 in AC circuits, representing how effectively current is being converted into useful work.

Q2: When should I use a power factor less than 1?
A: For AC circuits with inductive or capacitive loads (motors, transformers, etc.), use the actual power factor which is typically 0.8-0.95 for most equipment.

Q3: What's the difference between real power and apparent power?
A: Real power (watts) does actual work, while apparent power (VA) is the product of voltage and current. The ratio is the power factor.

Q4: How does this relate to energy consumption?
A: Energy (kWh) is power (kW) multiplied by time (hours). Accurate power calculation helps estimate energy usage.

Q5: Can I use this for three-phase power?
A: For balanced three-phase systems, multiply by √3 (about 1.732). The formula becomes P = √3 × V × I × PF.