1. What is a Generator Size Calculator?

Definition: This calculator estimates the required generator size in kilowatts based on the total electrical load and a safety factor.

Purpose: It helps determine the appropriate generator capacity needed to power all connected electrical devices safely.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Generator size (kilowatts)
• \( P_{load} \) — Total load power (watts)
• \( SF \) — Safety factor (typically 1.25 for generators)

Explanation: The total load in watts is converted to kilowatts (divided by 1000) then multiplied by a safety factor to ensure adequate generator capacity.

3. Importance of Proper Generator Sizing

Details: Correct generator sizing ensures reliable power supply, prevents overload conditions, and extends equipment lifespan.

4. Using the Calculator

Tips: Enter the total load power in watts and safety factor (default 1.25). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why do we need a safety factor?
A: The safety factor accounts for startup surges, future expansion, and ensures the generator isn't constantly running at full capacity.

Q2: What's a typical safety factor?
A: Most applications use 1.25 (25% extra capacity), but critical systems may require 1.5 or higher.

Q3: How do I find the total load power?
A: Sum the wattage of all devices to be powered simultaneously, including their startup surge if applicable.

Q4: Should I include all devices in my home/business?
A: Only include devices that need to run during power outages or that will be connected to the generator.

Q5: Does this account for three-phase power?
A: This calculator provides basic sizing. For three-phase systems, consult an electrician for proper calculations.