1. What is a Voltage Drop Calculator (CEC)?

Definition: This calculator estimates voltage drop in electrical circuits according to Canadian Electrical Code (CEC) standards.

Purpose: It helps electricians and engineers ensure proper voltage levels in electrical installations by calculating expected voltage drop.

2. How Does the Calculator Work?

The calculator uses the CEC voltage drop formula:

Where:

• \( VD \) — Voltage drop (volts)
• \( \rho \) — Resistivity of conductor material (ohm-m)
• \( L \) — Length of conductor (meters)
• \( I \) — Current flowing through conductor (amps)
• \( A \) — Cross-sectional area of conductor (m²)

Explanation: The formula accounts for both the outgoing and return paths (hence the factor of 2) in single-phase systems.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical equipment receives adequate voltage for proper operation and prevents excessive power loss.

4. Using the Calculator

Tips: Enter the conductor resistivity (default 1.72×10⁻⁸ ohm-m for copper), length in meters, current in amps, and conductor cross-sectional area in m². All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is the factor 2 used in the formula?
A: The factor 2 accounts for both the "go" and "return" paths in single-phase circuits (total conductor length is twice the one-way distance).

Q2: What's the typical resistivity for copper conductors?
A: Copper at 20°C has ρ ≈ 1.72×10⁻⁸ ohm-m. For aluminum, use ρ ≈ 2.65×10⁻⁸ ohm-m.

Q3: How does temperature affect the calculation?
A: Resistivity increases with temperature. For precise calculations, adjust ρ based on operating temperature.

Q4: What's the maximum acceptable voltage drop?
A: CEC recommends ≤3% for feeders and ≤5% for branch circuits of the supply voltage.

Q5: How do I convert wire gauge to cross-sectional area?
A: Use standard wire gauge tables. For example, 14 AWG ≈ 2.08 mm² = 2.08×10⁻⁶ m².