Cable Sizing & Voltage Drop Calculator

High-precision 3-phase low-voltage (LV) conductor sizing, continuous ampacity verification, and voltage drop simulation engine based on Engr. Didar Mia's computational model.

Tools Hub

Electrical System Parameters

Parameter Input

Nominal System Line Voltage

Operating Voltage Volts (V)

Three-Phase Load Input Mode

Input Power Kilowatt (kW)

Power Factor (cos θ) Lagging

Route Distance & Conductor Runs

Distance Meter (m)

Cables per Phase Parallel Runs

Cable Specification & Insulation Type

Insulation / Cable Type BDS / IEC Standards

Conductor Dimensioning Results

NYY Insulation @ 35°C

Copper (Cu)

NYY

Awaiting Parameters

Recommended Conductor Size

—

Current Carrying Capacity —

Voltage Drop (Volts) —

Voltage Drop (%) —

Receiving End Voltage —

Conductor Area (cmil) —

Awaiting Parameters

Aluminium (Al)

NYY

Awaiting Parameters

Recommended Conductor Size

—

Current Carrying Capacity —

Voltage Drop (Volts) —

Voltage Drop (%) —

Receiving End Voltage —

Conductor Area (cmil) —

Awaiting Parameters

Load Current

—

Design Current

—

Active Power

—

Circuit Length

—

Cu Voltage Drop

—

Al Voltage Drop

—

Voltage Drop vs. Route Distance

IEC 5% Threshold

Ampacity vs. Load Demand

Continuous Amperes

Terminal Receiving Voltage

Source: 415 V

Cross-Sectional Area (cmil)

Conductor Volume

Cu Sized Al Sized

#	Cable Size (RM)	Copper Rating (A)	Aluminium Rating (A)	Area (cmil / CM)	Approx mm²	Max Continuous kW (Cu)	Max Continuous kW (Al)

BESS / Battery Bank Sizing Companion (from Sheet 2)

Energy Storage

Battery Nominal Voltage V

Unit Battery Capacity Ah

Critical Load kW

Required Backup Hours

Depth of Discharge (DOD) Ratio

Inverter / System Efficiency Ratio

Formula: (Load kW × Backup hr × 1000) / (DOD × Eff × V × Ah)

Total Required Storage: 76.8 kWh

Required Batteries

63 Pcs (62.75)

Verified Computational Formulations

IEEE / IEC Reference

1. Three-Phase Load Current

I = (P × 1000) / (√3 × V × cos θ)

Computes continuous line current from active power, system voltage, and power factor.

2. Design Current with Safety Buffer

I_design = I_load + 20 A

As specified in Excel datasheet (cell I14), adds a 20 A continuous buffer to prevent thermal overload.

3. Voltage Drop in Volts (ΔV)

ΔV = (√3 × K × I_design × L_ft) / (cmil × n)

Classic 3-phase conductor drop where K_cu = 12.9, K_al = 21.2, L is distance in feet, and n is parallel runs.

4. Voltage Drop Percentage & Terminal Voltage

V_drop% = (ΔV / V) × 100% | V_rec = V - ΔV

Complies with IEC 60364-5-52 maximum allowable 5.0% threshold for power installations.

IEC 60364-5-52 BDS 675:2020 Standard 35°C Ambient Baseline 5.0% Max Voltage Drop (IEC)