1. What is a Portable 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 homeowners and professionals determine the appropriate generator capacity for backup power needs.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Generator size needed (kilowatts)
• \( \Sigma P_{load} \) — Total electrical load (watts)
• \( SF \) — Safety factor (typically 1.2 for residential use)

Explanation: The total load in watts is converted to kilowatts (divided by 1000) then multiplied by a safety factor to account for startup surges and future needs.

3. Importance of Proper Generator Sizing

Details: Correct generator sizing ensures reliable power during outages, prevents overload damage, and maximizes fuel efficiency.

4. Using the Calculator

Tips: Enter the total wattage of all appliances you want to power simultaneously and a safety factor (default 1.2). 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 (especially for motors) and provides capacity for future additions.

Q2: What's a typical safety factor?
A: For residential use, 1.2 is common. For commercial/industrial with large motors, 1.5-2.0 may be needed.

Q3: How do I find my total load?
A: Add up the wattage of all appliances you want to run simultaneously. Check appliance nameplates or manuals.

Q4: Should I include all my home's circuits?
A: No, only include essential circuits you need during an outage. Prioritize refrigerators, lights, etc.

Q5: Does this account for starting watts?
A: The safety factor helps, but for large motors (AC units, pumps), you may need to add their starting watts separately.