1. What is the Breaker Size Calculation?

The breaker size calculation determines the appropriate circuit breaker size needed to protect an electrical circuit based on the load current. The 1.25 multiplier provides a safety margin to prevent nuisance tripping while ensuring protection.

2. How Does the Calculator Work?

The calculator uses the standard formula:

Where:

• \( Load\ Current \) — The continuous current drawn by the electrical load
• \( 1.25 \) — Safety factor (125% of load current)

Explanation: The 1.25 multiplier accounts for continuous loads (those operating for 3+ hours) as required by electrical codes.

3. Importance of Proper Breaker Sizing

Details: Correct breaker sizing is crucial for electrical safety - too small and it will trip unnecessarily, too large and it won't provide proper protection against overloads.

4. Using the Calculator

Tips: Enter the load current in amps. The value must be positive. For motor loads or special applications, additional factors may apply.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 1.25?
A: The 1.25 factor (125%) is required by electrical codes for continuous loads to prevent overheating of conductors.

Q2: What's the difference between breaker size and wire size?
A: Breaker size protects the circuit, while wire size must be adequate for both current and breaker protection.

Q3: When should I use the next standard breaker size?
A: If the calculation results in a non-standard size (e.g., 18.75A), round up to the next standard size (20A in this case).

Q4: Are there exceptions to this rule?
A: Yes, certain loads like motors have different sizing requirements based on their starting current.

Q5: What about multiple loads on one circuit?
A: For multiple loads, calculate the total current first, then apply the 1.25 factor to the total.