How does insulation affect ampacity (amps)?

The higher the temperature rating of an insulation the higher the amp rating. For example, a single conductor 2 AWG with 90°C PVC insulation in free air has an ampacity rating of (approximately) 185 amps. Now take the same conductor and use a 200°C silicone insulation in free air and it will have an ampacity rating of 240 amps.

Higher insulation temperature rating = Higher ampacity rating

Written by Leo Cole