1. What is 3 Phase Motor Power Calculator?

Definition: This calculator estimates the power consumption of a three-phase electric motor in kilowatts (kW) based on voltage, current, and power factor.

Purpose: It helps electrical engineers, technicians, and maintenance personnel determine motor power requirements and energy consumption.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Power in kilowatts (kW)
• \( V \) — Line-to-line voltage (volts)
• \( I \) — Current (amps)
• \( PF \) — Power factor (0 to 1)
• \( \sqrt{3} \) — Constant for three-phase systems (≈1.732)

Explanation: The formula calculates real power by accounting for both the apparent power (V×I) and the power factor (cosine of phase angle between voltage and current).

3. Importance of Power Calculation

Details: Accurate power calculation helps in sizing electrical components, estimating energy costs, and ensuring proper motor operation.

4. Using the Calculator

Tips: Enter the line-to-line voltage in volts, current in amps, and power factor (default 0.85). All values must be > 0, and PF between 0 and 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 (typically 0.8-0.95 for motors).

Q2: Should I use line or phase voltage?
A: Use line-to-line voltage (typically 208V, 230V, 380V, 400V, 415V, 480V, etc. depending on your system).

Q3: What if I only have phase current?
A: For delta connections, line current = phase current × √3. For wye connections, line current = phase current.

Q4: How accurate is this calculation?
A: It provides theoretical power. Actual power may vary due to efficiency losses, voltage drops, and harmonics.

Q5: Can I calculate horsepower from this result?
A: Yes, 1 HP ≈ 0.746 kW. Multiply kW by 1.341 to get horsepower.