As already discussed in Ampacity of a Conductor, the ampacity of a conductor depends on temperature. Any change in ambient temperature affects the ampacity of an electrical cable. When this happens, correction factors are applied to get new ratings for such a conductor.
The approximate ampacity correction factors for all cables under different ambient temperature conditions for cables whose insulation is rated 90 degree C are given below:
The approximate ampacity correction factors for all cables under different ambient temperature conditions for cables whose insulation is rated 90 degree C are given below:
| Ambient Temperature | Correction Factors for Cable Insulation Rated At: |
| (°C) | 90°C |
| 10 | 1.26 |
| 20 | 1.18 |
| 30 | 1.10 |
| 40 | 1.00 |
| 50 | 0.90 |