1. What is Generator Sizing?

Generator sizing is the process of determining the appropriate capacity (in kVA) of a generator needed to power all connected electrical loads in a home or facility. Proper sizing ensures reliable operation without overloading the generator.

2. How Does the Calculator Work?

The calculator uses the generator sizing formula:

Where:

• \( \sum Loads \) — Sum of all electrical loads in watts
• \( Power Factor \) — Ratio of real power to apparent power (typically 0.8 for homes)

Explanation: The formula converts the total wattage of all connected devices to kVA (kilovolt-amperes), which is the standard rating for generators.

3. Importance of Proper Generator Sizing

Details: Correct generator sizing prevents damage to both the generator and connected equipment. An undersized generator may fail to start motors or trip circuit breakers, while an oversized generator operates inefficiently.

4. Using the Calculator

Tips:

• Calculate your total load by adding up the wattage of all devices you want to power simultaneously
• For motor loads (AC, refrigerator), use the starting wattage (typically 3x running wattage)
• Typical home power factor is 0.8 unless you know otherwise

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between kW and kVA?
A: kW (kilowatts) is real power, while kVA (kilovolt-amperes) is apparent power. The ratio between them is the power factor (kW/kVA).

Q2: What power factor should I use for my home?
A: Most homes have a power factor between 0.8-0.95. 0.8 is a safe default for calculations.

Q3: Should I add a safety margin to the calculated size?
A: Yes, it's recommended to add 20-25% to the calculated size for future expansion and load variations.

Q4: How do I find the wattage of my appliances?
A: Check nameplates or manuals. Typical values: Refrigerator (600W), AC (1500W), Lights (60W/bulb), TV (200W).

Q5: What about three-phase power?
A: This calculator is for single-phase systems. Three-phase calculations require additional factors.