1. What is AC Power Calculation?

Definition: This calculator computes the real power in watts for AC circuits based on current, voltage, and power factor.

Purpose: It helps electricians, engineers, and homeowners determine the actual power consumption of AC electrical devices.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P \) — Real power (watts)
• \( V \) — Voltage (volts, default 120V)
• \( I \) — Current (amperes)
• \( PF \) — Power factor (dimensionless, 0 to 1)

Explanation: The voltage and current are multiplied together with the power factor to account for phase differences in AC circuits.

3. Importance of Power Calculation

Details: Accurate power calculation ensures proper circuit sizing, energy efficiency, and prevents electrical overloads.

4. Using the Calculator

Tips: Enter the current in amps, voltage (default 120V), and power factor (default 1.0 for resistive loads). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor represents the ratio of real power to apparent power, ranging from 0 to 1. 1.0 indicates perfect efficiency.

Q2: Why is voltage fixed at 120V?
A: 120V is standard for North American residential circuits, but you can change it for other applications.

Q3: What's a typical power factor value?
A: Resistive loads (heaters, incandescent lights) have PF=1.0. Motors may have PF=0.8-0.9. Electronics often have lower PFs.

Q4: How do I measure current?
A: Use a clamp meter or multimeter to measure current in the circuit.

Q5: Does this work for three-phase power?
A: No, this is for single-phase AC. Three-phase requires a different formula.