kWh Formula 3 Phase

3-Phase Energy Formula:

\[ E_{kWh} = \frac{V \times I \times PF \times \sqrt{3} \times t}{1000} \]

Voltage (V):

volts

Current (I):

amps

Power Factor (PF):

Time (t):

hours

Energy (E_kWh): kWh

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1. What is 3-Phase Energy Calculation?

Definition: This calculator computes the energy consumption in kilowatt-hours (kWh) for a three-phase electrical system.

Purpose: It helps electricians, engineers, and facility managers estimate energy usage in three-phase power systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ E_{kWh} = \frac{V \times I \times PF \times \sqrt{3} \times t}{1000} \]

Where:

\( E_{kWh} \) — Energy in kilowatt-hours
\( V \) — Line voltage (volts)
\( I \) — Current (amps)
\( PF \) — Power factor (0 to 1)
\( t \) — Time (hours)
\( \sqrt{3} \) — Constant for three-phase systems (≈1.732)

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

3. Importance of 3-Phase Energy Calculation

Details: Accurate energy calculation helps in power monitoring, billing, energy efficiency analysis, and electrical system design.

4. Using the Calculator

Tips: Enter the line voltage (V), current (I), power factor (default 0.9), and operating time in hours. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor and why is it important?
A: Power factor (0-1) represents efficiency of power usage. Lower PF means more apparent power is needed for the same real power.

Q2: How does this differ from single-phase calculation?
A: Single-phase uses V×I×PF×t/1000. Three-phase adds the √3 factor to account for the three phases.

Q3: What's a typical power factor value?
A: Motors typically have PF of 0.8-0.9. Resistive loads have PF=1. The default 0.9 is common for industrial loads.

Q4: Should I use line-to-line or line-to-neutral voltage?
A: Use line-to-line voltage (the higher value) for this calculation.

Q5: How accurate is this calculation?
A: It provides theoretical values. Actual consumption may vary due to voltage fluctuations, harmonics, and other factors.