1. What is AC Power Calculation?

Definition: This calculator computes the real power (in watts) in an AC circuit based on voltage, current, and power factor.

Purpose: It helps electricians, engineers, and technicians determine the actual power consumption of AC equipment like motors and air conditioners.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_w \) — Real power (watts)
• \( V \) — Voltage (volts)
• \( I \) — Current (amps)
• \( PF \) — Power factor (unitless, between 0 and 1)

Explanation: The formula calculates the actual power being used in the circuit, accounting for the phase difference between voltage and current.

3. Importance of AC Power Calculation

Details: Accurate power calculation ensures proper equipment sizing, energy efficiency, and electrical system safety.

4. Using the Calculator

Tips: Enter the voltage in volts, current in amps, and power factor (default 0.8). All values must be > 0, with 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 how effectively current is being converted into useful work.

Q2: What's a typical power factor value?
A: For motors, it's typically 0.8-0.9; for air conditioners, 0.7-0.9. Pure resistive loads have PF=1.

Q3: Why is my calculated power less than voltage × current?
A: Because real power is only part of the total apparent power (VA) in AC systems when PF < 1.

Q4: How do I measure current and voltage?
A: Use a multimeter - measure voltage across the load and current in series with the load.

Q5: Does this work for three-phase systems?
A: No, this is for single-phase. Three-phase requires multiplying by √3 (1.732).