3 Phase Motor Power Calculator

3 Phase Motor Power Formula:

\[ P = \sqrt{3} \times V \times I \times PF \times Eff \]

Voltage (V):

Current (I):

Power Factor (PF):

(0-1)

Efficiency (Eff):

(0-1)

Power Output (P):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is 3 Phase Motor Power Calculation?

The 3 phase motor power calculation determines the real power output of a three-phase electric motor. It accounts for voltage, current, power factor, and efficiency to provide an accurate measurement of the motor's actual power consumption and output.

2. How Does the Calculator Work?

The calculator uses the 3 phase power formula:

\[ P = \sqrt{3} \times V \times I \times PF \times Eff \]

Where:

\( P \) — Power output in watts (W)
\( V \) — Line-to-line voltage in volts (V)
\( I \) — Current in amperes (A)
\( PF \) — Power factor (unitless, 0 to 1)
\( Eff \) — Motor efficiency (unitless, 0 to 1)
\( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula calculates real power by accounting for both the apparent power (V×I) and the power factor (which represents phase difference between voltage and current), then adjusts for motor efficiency.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for proper motor sizing, energy efficiency assessment, electrical system design, and cost estimation. It helps prevent overloading and ensures optimal performance.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, power factor (typically 0.8-0.95 for motors), and efficiency (typically 0.85-0.95 for modern motors). All values must be positive numbers within their valid ranges.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between real power and apparent power?
A: Real power (W) is the actual power consumed, while apparent power (VA) is the product of voltage and current. The ratio is the power factor.

Q2: Why is power factor important?
A: Lower power factor means more current is needed for the same real power, increasing losses and requiring larger conductors.

Q3: What are typical efficiency values for motors?
A: Standard motors: 85-90%, High-efficiency motors: 90-95%, Premium efficiency motors: 95-97%.

Q4: Should I use line-to-line or line-to-neutral voltage?
A: Always use line-to-line voltage for 3-phase power calculations.

Q5: How does this differ from single-phase power calculation?
A: Single-phase uses P = V×I×PF×Eff without the √3 factor, and uses line-to-neutral voltage.