1. What is Panel Load Calculation?

The Circuit Breaker Panel Load Calculation determines the total electrical load on a panel by summing all branch circuit loads and applying a 25% continuous load factor for safety.

2. How Does the Calculator Work?

The calculator uses the panel load formula:

Where:

• \( \sum(Branch\ Loads) \) — Sum of all individual circuit loads in amps
• 1.25 — 25% continuous load safety factor

Explanation: The 25% factor accounts for continuous loads (those expected to last 3+ hours) which generate more heat and require derating.

3. Importance of Panel Load Calculation

Details: Proper panel load calculation ensures electrical systems operate safely within their rated capacities, preventing overheating and potential fire hazards.

4. Using the Calculator

Tips: Enter the total of all branch circuit loads in amps. The value must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: Why use a 25% factor?
A: The 25% margin accounts for continuous loads (NEC requirement) and provides a safety buffer for potential load additions.

Q2: What's considered a continuous load?
A: Any load expected to operate for 3+ hours continuously (lighting, HVAC, refrigeration, etc.).

Q3: How do I measure branch loads?
A: Sum the nameplate ratings or use clamp-on ammeter measurements of each circuit.

Q4: What if my panel load exceeds capacity?
A: Consider redistributing loads, adding a subpanel, or upgrading your main panel with professional assistance.

Q5: Does this apply to subpanels?
A: Yes, the same calculation method applies to main panels and subpanels.