1. What is a Voltage Drop Calculator for Aluminium Cable?

Definition: This calculator estimates the voltage drop in an aluminium cable based on its length, current load, and cross-sectional area.

Purpose: It helps electrical engineers and technicians ensure proper voltage levels in electrical installations using aluminium cables.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( VD \) — Voltage drop (volts)
• \( \rho_{al} \) — Resistivity of aluminium (2.82×10⁻⁸ ohm-m)
• \( L \) — Cable length (meters)
• \( I \) — Current (amps)
• \( A \) — Cross-sectional area (m²)

Explanation: The factor of 2 accounts for the return path in single-phase systems. The formula calculates the voltage loss due to cable resistance.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical devices receive adequate voltage, prevents power loss, and maintains system efficiency.

4. Using the Calculator

Tips: Enter the cable length in meters, current in amps, and cross-sectional area in square meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is aluminium resistivity important?
A: Aluminium has higher resistivity than copper (2.82×10⁻⁸ vs 1.68×10⁻⁸ ohm-m), making voltage drop calculations crucial for aluminium cables.

Q2: What's a typical acceptable voltage drop?
A: Most standards recommend ≤3% voltage drop for power circuits and ≤5% for lighting circuits from source to load.

Q3: Does this work for three-phase systems?
A: For balanced three-phase systems, replace the factor 2 with √3 (approximately 1.732).

Q4: How do I find the cross-sectional area?
A: Check cable specifications or measure diameter and use \( A = \pi r^2 \) for round cables.

Q5: What affects aluminium resistivity?
A: Temperature and purity affect resistivity. The calculator uses standard 20°C pure aluminium value.