1. What is the Wattage Formula?

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

2. How Does the Calculator Work?

The calculator uses the Wattage 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 efficiency 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, typically 0.8-0.95 for AC). All values must be valid (positive numbers, PF between 0-1).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between real power and apparent power?
A: Real power (P, in watts) is the actual power consumed. Apparent power (S, in VA) is V×I. The ratio P/S is the power factor.

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

Q3: How can I improve power factor?
A: By adding capacitors (for inductive loads) or inductors (for capacitive loads) to bring current waveform in phase with voltage.

Q4: What's a typical power factor for household appliances?
A: Resistive loads (heaters, incandescent lights) have PF=1. Motors typically 0.8-0.9. Electronics with power supplies often 0.6-0.7.

Q5: Why is low power factor a problem?
A: It increases current for the same real power, requiring larger conductors and causing greater energy losses in distribution systems.