1. What is a Single Phase kWh Meter?

Definition: This calculator measures energy consumption in kilowatt-hours (kWh) for single-phase electrical systems.

Purpose: It helps homeowners, electricians, and engineers calculate electrical energy usage for single-phase appliances and circuits.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( E_{kWh} \) — Energy consumption (kilowatt-hours)
• \( V \) — Voltage (volts)
• \( I \) — Current (amperes)
• \( PF \) — Power factor (unitless, 0 to 1)
• \( t \) — Time (hours)

Explanation: The formula calculates real power consumption by accounting for voltage, current, power factor, and duration of use.

3. Importance of Energy Calculation

Details: Accurate energy measurement helps in electricity billing, energy efficiency assessments, and electrical system design.

4. Using the Calculator

Tips: Enter the voltage (typically 120V or 240V for residential), current (measured or rated), power factor (1.0 for resistive loads), and time in hours. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor (PF) is the ratio of real power to apparent power, ranging from 0 to 1. Resistive loads (like heaters) have PF=1, while inductive loads (like motors) have PF<1.

Q2: How do I find the current value?
A: Use a clamp meter to measure actual current, or check the appliance nameplate for rated current.

Q3: What's the difference between single-phase and three-phase?
A: Single-phase has two wires (live and neutral), while three-phase has three live wires. This calculator is for single-phase only.

Q4: Why divide by 1000?
A: The division converts watt-hours to kilowatt-hours (kWh), the standard unit for electricity billing.

Q5: Can I use this for DC circuits?
A: Yes, but set power factor to 1.0 since DC has no reactive power component.