3 Phase Amperes Calculator

3-Phase Current Formula:

\[ Current = \frac{Power}{\sqrt{3} \times Voltage \times Power\ Factor} \]

Current:

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1. What is 3-Phase Current Calculation?

The 3-phase current calculation determines the current (amperes) flowing in a three-phase electrical system given the power, voltage, and power factor. This is essential for proper sizing of electrical components and circuit protection.

2. How Does the Calculator Work?

The calculator uses the 3-phase current formula:

\[ Current = \frac{Power}{\sqrt{3} \times Voltage \times Power\ Factor} \]

Where:

\( Power \) — Total power in watts (W)
\( Voltage \) — Line-to-line voltage in volts (V)
\( Power\ Factor \) — Ratio of real power to apparent power (0 to 1)
\( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The equation calculates the current required to deliver a certain power at a given voltage, accounting for the phase relationship in 3-phase systems and the power factor.

3. Importance of Current Calculation

Details: Accurate current calculation is crucial for selecting proper wire sizes, circuit breakers, overload protection, and ensuring safe operation of electrical equipment.

4. Using the Calculator

Tips: Enter power in watts, voltage in volts, and power factor (between 0 and 1). All values must be positive numbers. The power factor is typically between 0.8 and 1 for most industrial applications.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is between any two phases, while line-to-neutral is between one phase and neutral. The calculator uses line-to-line voltage.

Q2: What if I know kVA instead of watts?
A: For apparent power (kVA), set power factor to 1 in the calculation (kVA × 1000 = watts when PF=1).

Q3: What's a typical power factor value?
A: Motors typically have 0.8-0.9 PF, resistive loads have 1.0 PF, and heavily inductive loads may have lower PF.

Q4: How does this differ from single-phase current calculation?
A: Single-phase uses Power/(Voltage×PF) without the √3 factor. 3-phase is more efficient for power delivery.

Q5: Why is the result important for electrical design?
A: Current determines conductor sizing, protection device ratings, and voltage drop calculations in electrical systems.