1. What is Cable Ampacity?

Ampacity is the maximum current a conductor can carry continuously under the conditions of use without exceeding its temperature rating. It depends on wire size, material, and ambient temperature.

2. How Does the Calculator Work?

The calculator uses the ampacity formula:

Where:

• \( Size \) — Wire gauge in AWG
• \( Type \) — Conductor material (copper or aluminum)
• \( Temperature \) — Ambient temperature in °C

Explanation: The calculation accounts for the resistance characteristics of different materials and temperature derating factors.

3. Importance of Ampacity Calculation

Details: Proper ampacity calculation is crucial for electrical safety, preventing overheating, and ensuring code compliance in electrical installations.

4. Using the Calculator

Tips: Enter wire size in AWG, select conductor material, and ambient temperature. All values must be valid (size > 0, temperature > 0).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between copper and aluminum ampacity?
A: Copper generally has higher ampacity than aluminum for the same size due to better conductivity.

Q2: How does temperature affect ampacity?
A: Higher temperatures reduce allowable ampacity due to increased resistance and heat dissipation challenges.

Q3: What are standard ampacity tables based on?
A: NEC tables are based on specific installation conditions (e.g., 30°C ambient, 3 current-carrying conductors).

Q4: When should I derate ampacity?
A: Derating is needed for high ambient temperatures, multiple conductors in a raceway, or other special conditions.

Q5: Is this calculator suitable for all installations?
A: For critical applications, always consult the latest NEC tables and consider all installation factors.