⚡ CircuitSecrets
Busbar Current Capacity Calculator
Professional busbar sizing for Copper, Aluminium, Iron, GI & Silver — with temperature derating, voltage drop, resistance & weight estimation
Copper
Aluminium
GI / Iron
Temperature Derating
Voltage Drop
Weight Estimate
Busbar Sizing
Input Parameters
Material Selection
All
Copper
Aluminium
Iron
GI
Silver
Cross-Section Dimensions
Temperature & Derating
Advanced Options
Sizing Result
Calculation Results
W: 50 mmT: 10 mmA: 500 mm²
Copper Busbar
—
Amperes (derated)
► Formulas & Method
Busbar Capacity Method
Base Capacity: I = J × A (A/mm² × mm²)
Derating Factor: k = √((T_max − T_amb)/(T_max − 40))
Derated Current: I_d = I_base × k
Resistance: R = ρ × L / A (Ω)
Voltage Drop: V = I × R (V)
Weight: W = A × L × density (kg)
J: Cu 1.5 · Al 0.8 · Fe 0.6 · GI 0.5 · Ag 2.0 A/mm²
⚠ Note: Values based on standard current density ratings. Actual capacity depends on mounting, enclosure, ventilation & skin effect. Consult IEC 61439 for panel applications.
