1. What is a Secondary Wire Size Calculator?

Definition: This calculator determines the minimum cross-sectional area of a wire needed to safely carry a given electrical current.

Purpose: It helps electricians and engineers select properly sized wires to prevent overheating and ensure electrical safety.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( A \) — Wire cross-sectional area (m²)
• \( I \) — Current (amps)
• \(\text{ampacity}\) — Current carrying capacity per unit area (A/m²)

Explanation: The current is divided by the ampacity rating to determine the minimum wire size needed to safely carry that current.

3. Importance of Proper Wire Sizing

Details: Correct wire sizing prevents overheating, voltage drop, and potential fire hazards while ensuring efficient power transmission.

4. Using the Calculator

Tips: Enter the current in amps and the ampacity rating (default 1000 A/m² for copper). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is ampacity?
A: Ampacity is the maximum current a conductor can carry before exceeding its temperature rating.

Q2: What's a typical ampacity value?
A: For copper wire, ampacity is typically around 1000 A/m², but varies with insulation type and ambient temperature.

Q3: How do I convert this result to AWG or mm²?
A: Use a wire gauge chart to find the nearest standard size that meets or exceeds your calculated area.

Q4: Does this account for voltage drop?
A: No, this calculates minimum size for ampacity only. Longer runs may require larger wires to limit voltage drop.

Q5: What safety factors should I consider?
A: Always consult electrical codes and consider derating factors for temperature, bundling, and continuous loads.