Wire Size and Length Calculator

Wire Size Equation:

\[ \text{Wire Size (mm²)} = \frac{\text{Current (A)} \times \text{Length (m)}}{\text{Voltage Drop (V)}} \]

Wire Size (approx):

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1. What is the Wire Size Calculation?

The wire size calculation determines the appropriate cross-sectional area of a wire needed to carry a specific current over a certain distance while maintaining acceptable voltage drop.

2. How Does the Calculator Work?

The calculator uses the wire size equation:

\[ \text{Wire Size (mm²)} = \frac{\text{Current (A)} \times \text{Length (m)}}{\text{Voltage Drop (V)}} \]

Where:

\( Current \) — Electrical current in Amperes (A)
\( Length \) — Wire length in meters (m)
\( Voltage Drop \) — Acceptable voltage drop in Volts (V)

Explanation: The equation calculates the minimum wire size needed to maintain the specified voltage drop for the given current and wire length.

3. Importance of Proper Wire Sizing

Details: Correct wire sizing is crucial for electrical safety, preventing overheating, ensuring proper voltage at load, and complying with electrical codes.

4. Using the Calculator

Tips: Enter current in Amperes, length in meters, and acceptable voltage drop in Volts. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is an acceptable voltage drop?
A: Typically 3% for branch circuits and 5% for feeder circuits, but check local electrical codes for specific requirements.

Q2: Does this account for temperature and insulation type?
A: This is a basic calculation. For precise sizing, consult wire ampacity tables considering insulation type and ambient temperature.

Q3: What about three-phase systems?
A: This calculator is for DC or single-phase AC. Three-phase calculations require different formulas.

Q4: How do I convert AWG to mm²?
A: Common conversions: 14 AWG = 2.08 mm², 12 AWG = 3.31 mm², 10 AWG = 5.26 mm², etc. Use an AWG to mm² conversion chart.

Q5: Should I round up the calculated size?
A: Yes, always round up to the next standard wire size for safety and to account for real-world conditions.