1. What is 3-Phase Motor Power Calculation?

The 3-phase motor power calculation determines the real power (kW) consumed by an electric motor based on voltage, current, power factor, and efficiency. This helps in proper motor sizing and energy consumption analysis.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

• \( Voltage \) — Line-to-line voltage (V)
• \( Current \) — Phase current (A)
• \( Power\ Factor \) — Ratio of real power to apparent power (0-1)
• \( Efficiency \) — Motor efficiency (0-1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula accounts for all three phases in the system and converts the result to kilowatts by dividing by 1000.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for proper motor selection, energy efficiency analysis, electrical system design, and cost estimation.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, power factor (typically 0.8-0.95), and motor efficiency (typically 0.85-0.95). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power (kW) to apparent power (kVA), representing how effectively current is converted to useful work.

Q2: How do I find motor efficiency?
A: Efficiency is typically listed on the motor nameplate or in manufacturer specifications. Standard motors range from 85-95% efficient.

Q3: Is this for line or phase voltage?
A: The formula uses line-to-line voltage (phase-to-phase voltage) which is what you'd measure between any two power conductors.

Q4: Can I use this for single-phase motors?
A: No, this calculator is specifically for 3-phase systems. Single-phase motors use a different formula without the √3 factor.

Q5: Why is the result in kW?
A: Kilowatts represent real power, which is what you're billed for and what actually performs work, as opposed to apparent power (kVA).