1. What is a Three Phase Watts Calculator?

Definition: This calculator computes the real power (in watts) in a three-phase electrical system based on voltage, current, and power factor.

Purpose: It helps electricians, engineers, and technicians determine the actual power consumption in three-phase AC circuits.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_w \) — Real power (watts)
• \( V \) — Line-to-line voltage (volts)
• \( I \) — Current (amps)
• \( PF \) — Power factor (unitless, between 0 and 1)
• \( \sqrt{3} \) — Constant for three-phase systems (≈1.732)

Explanation: The formula accounts for all three phases in the system and the phase relationship between voltage and current.

3. Importance of Three Phase Power Calculation

Details: Accurate power calculation is essential for proper circuit design, equipment sizing, energy efficiency analysis, and electrical safety.

4. Using the Calculator

Tips: Enter the line-to-line 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's the difference between line-to-line and line-to-neutral voltage?
A: In three-phase systems, line-to-line voltage is √3 times the line-to-neutral voltage. This calculator uses line-to-line voltage.

Q2: What is power factor and why does it matter?
A: Power factor represents the ratio of real power to apparent power. It accounts for phase differences between voltage and current.

Q3: What's a typical power factor value?
A: For motors, 0.8-0.9 is common. Resistive loads have PF=1, while inductive loads have lower PF.

Q4: Can I use this for single-phase calculations?
A: No, for single-phase use P = V × I × PF (without the √3 factor).

Q5: How does this relate to kVA and kW?
A: kW is real power (this calculation), kVA is apparent power (V × I × √3). kW = kVA × PF.