1. What is a Conduit Size Calculator by Wires?

Definition: This calculator determines the minimum conduit diameter needed based on the total cross-sectional area of wires and the maximum fill percentage allowed.

Purpose: It helps electricians and engineers properly size conduits to meet electrical code requirements and ensure safe wire installation.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( D \) — Conduit diameter (meters)
• \( \sum A \) — Sum of all wire cross-sectional areas (square meters)
• \( F \) — Fill percentage (as decimal, e.g., 40% = 0.40)
• \( \pi \) — Pi constant (~3.1416)

Explanation: The formula calculates the minimum conduit diameter that can accommodate the total wire area while respecting the maximum fill percentage.

3. Importance of Proper Conduit Sizing

Details: Correct conduit sizing prevents overheating, allows for heat dissipation, makes pulling wires easier, and complies with electrical codes.

4. Using the Calculator

Tips: Enter the sum of all wire cross-sectional areas in m² and the maximum fill percentage (default 40%). All values must be > 0 and fill percentage ≤ 100.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical fill percentage?
A: Electrical codes typically specify 40% fill for 3 or more wires, 53% for 2 wires, and 60% for 1 wire.

Q2: How do I find wire cross-sectional areas?
A: For round wires: \( A = \pi \times r^2 \). For multiple wires, sum all individual areas.

Q3: Should I round up the conduit size?
A: Yes, always round up to the next available standard conduit size for practical installation.

Q4: Does this account for wire insulation?
A: Yes, the wire area should include the insulation - use the outer diameter for calculations.

Q5: Can I use this for non-circular conduits?
A: This calculator is for circular conduits. For other shapes, different formulas apply.