1. What is a Wire Size And Length Calculator?

Definition: This calculator determines the appropriate wire gauge (AWG) needed based on voltage drop, length, current, voltage, and a material constant.

Purpose: It helps electricians and engineers select the proper wire size to ensure safe and efficient electrical installations.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{Size} \) — Wire gauge (AWG)
• \( \text{Voltage Drop} \) — Maximum allowable voltage drop (V)
• \( \text{Length} \) — Length of wire run (ft)
• \( \text{Current} \) — Current load (A)
• \( \text{Voltage} \) — Circuit voltage (V)
• \( \text{Constant} \) — Material constant (10.75 for copper)

Explanation: The formula calculates the minimum wire size needed to maintain voltage drop within acceptable limits for a given current over a specified distance.

3. Importance of Proper Wire Sizing

Details: Correct wire sizing prevents excessive voltage drop, reduces heat generation, and ensures electrical safety and efficiency.

4. Using the Calculator

Tips: Enter the maximum allowable voltage drop, wire length, current load, circuit voltage (default 120V), and material constant (default 10.75 for copper). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical acceptable voltage drop?
A: For most circuits, 3% is recommended for branch circuits and 5% for feeder circuits.

Q2: What constant should I use for aluminum wire?
A: Use 17.0 for aluminum conductors instead of the default 10.75 for copper.

Q3: Does this account for temperature variations?
A: No, for high-temperature environments, consult NEC tables or derating factors.

Q4: How do I convert AWG to actual wire diameter?
A: AWG is a logarithmic scale - refer to AWG size charts for diameter in inches or mm.

Q5: Should I round up the calculated wire size?
A: Yes, always round up to the next standard AWG size for safety.