1. What is the 3-Phase Electric Motor Power Formula?

The 3-phase electric motor power formula calculates the real power consumption of a three-phase motor in kilowatts. This formula is essential for electrical engineers, technicians, and maintenance personnel to determine motor performance and energy consumption.

2. How Does the Calculator Work?

The calculator uses the standard 3-phase power formula:

Where:

• \( \sqrt{3} \) — Mathematical constant (approximately 1.732)
• \( Voltage \) — Line-to-line voltage in volts
• \( Current \) — Line current in amperes
• \( Power Factor \) — Ratio of real power to apparent power (0 to 1)
• \( 1000 \) — Conversion factor from watts to kilowatts

Explanation: This formula calculates the real power (active power) consumed by a 3-phase motor, taking into account the phase relationship between voltage and current through the power factor.

3. Importance of Motor Power Calculation

Details: Accurate power calculation is crucial for motor sizing, energy efficiency analysis, electrical system design, load management, and cost estimation in industrial and commercial applications.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, line current in amperes, and power factor (typically 0.8-0.95 for motors). All values must be positive and power factor must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor and why is it important?
A: Power factor represents the efficiency of power usage. A higher power factor (closer to 1) indicates more efficient power consumption and reduces energy losses.

Q2: What is the typical power factor for electric motors?
A: Most industrial motors operate at power factors between 0.8 and 0.95 when fully loaded. Power factor decreases at partial loads.

Q3: Can this formula be used for single-phase motors?
A: No, this formula is specifically for 3-phase systems. Single-phase motors use a different formula: Power (kW) = Voltage × Current × Power Factor / 1000.

Q4: What is the significance of √3 in the formula?
A: √3 accounts for the phase difference in 3-phase systems. It represents the ratio between line voltage and phase voltage in wye-connected systems.

Q5: How accurate is this calculation for motor sizing?
A: This provides theoretical power consumption. For motor selection, always consider safety factors, starting currents, and specific application requirements.