Thermal Derating

Calculate reduced ampacity for wires routed through high-temperature engine zones.

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Manual Calculation Formula:
Derated Amps = Base Amps * sqrt((Tc - Ta) / (Tc - 20))
Where Tc is the max conductor temp rating (e.g. 125°C for TXL) and Ta is the ambient engine bay temp.

Base Ampacity at 20°C (Amps)

Ambient Temperature (°C)

Wire Insulation Rating (°C)

Derated Ampacity

Warning: Ambient temp exceeds insulation rating!