⚡ Electrical Engineering
Voltage Drop Calculator
Calculate voltage drop, percentage drop, and minimum cable size for electrical circuits.
⚡ Circuit Parameters
Voltage
V
Current
A
🔌 Cable Details
Cable Length
m
Conductor Size
mm²
Conductor Material
Resistivity: Copper = 1.72×10⁻⁸ Ω·m
📊 Installation
Installation Type
Phase configuration
Temperature
°C
Standard: 20°C, derate for higher temps
Drop
0%
Voltage Drop
0 V
of supply voltage
Voltage Drop
0 V
Percentage Drop
0%
Receiving Voltage
0 V
Status
✅ OK
📊 Cable & Circuit Details
| Parameter | Value | Unit |
|---|
How the formula works
VD = (√3 × I × L × ρ × 2) / A | Single Phase: VD = (2 × I × L × ρ) / A
- VD = Voltage Drop (Volts)
- I = Current (Amperes)
- L = Cable Length (meters) — one-way
- ρ = Resistivity (Copper = 1.72×10⁻⁸, Aluminum = 2.82×10⁻⁸ Ω·m)
- A = Conductor Cross-Section Area (m²)
- % Drop = (VD ÷ Voltage) × 100
- Receiving Voltage = Voltage − VD
- For three-phase: √3 factor, single-phase: 2 factor (two-way length)
- Recommended: Drop should be ≤ 5% for general circuits