1. What is 3 Phase Current?

Three-phase current is a common method of electric power transmission used in the UK and worldwide. It consists of three alternating currents of the same frequency but offset in phase by 120 degrees, providing more efficient power distribution than single-phase systems.

2. How Does the Calculator Work?

The calculator uses the 3 phase current equation:

Where:

• \( I \) — Current in Amperes (A)
• \( P \) — Power in Watts (W)
• \( V \) — Line to Line Voltage in Volts (V)
• \( PF \) — Power Factor (0-1)

Explanation: The equation calculates the current drawn by a balanced three-phase load given the power, voltage, and power factor.

3. Importance of Current Calculation

Details: Accurate current calculation is essential for proper sizing of circuit breakers, cables, and other electrical components to ensure safety and prevent equipment damage.

4. Using the Calculator

Tips: Enter power in watts, voltage in volts, and power factor (typically 0.8-0.95 for most industrial loads). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical voltage for UK 3 phase systems?
A: In the UK, common three-phase voltages are 400V (line-to-line) and 230V (line-to-neutral).

Q2: What if my power factor is unknown?
A: For resistive loads (heaters, incandescent lights), use 1.0. For motors, 0.8 is a typical estimate if exact value is unknown.

Q3: Can I use this for single phase calculations?
A: No, this is specifically for three-phase systems. Single phase uses a different formula (I = P / (V × PF)).

Q4: Why is √3 used in the formula?
A: The √3 factor accounts for the phase difference between the three phases in a balanced system.

Q5: How accurate is this calculation?
A: The calculation is mathematically precise for balanced loads. Actual current may vary with unbalanced loads or harmonic distortion.