A derating factor is a multiplier (less than 1) applied to a cable’s rated current-carrying capacity to reduce its maximum allowable load. This ensures the cable operates within safe temperature limits under real-world conditions.
Note: Always check manufacturer tables for exact values. When multiple cables run together, each heats its neighbors. The closer and more cables, the higher the derating.
| | Arrangement | Derating factor | |----------------------|--------------------------------|---------------------| | 1 | Single circuit, free air | 1.00 | | 2–3 | Touching, in air | 0.80–0.85 | | 4–5 | Touching, in air | 0.70–0.75 | | 6–8 | Touching, in air | 0.60–0.65 | | >9 | Touching, in air | 0.50–0.55 |
Derating Factor For Cables |top| May 2026
A derating factor is a multiplier (less than 1) applied to a cable’s rated current-carrying capacity to reduce its maximum allowable load. This ensures the cable operates within safe temperature limits under real-world conditions.
Note: Always check manufacturer tables for exact values. When multiple cables run together, each heats its neighbors. The closer and more cables, the higher the derating. derating factor for cables
| | Arrangement | Derating factor | |----------------------|--------------------------------|---------------------| | 1 | Single circuit, free air | 1.00 | | 2–3 | Touching, in air | 0.80–0.85 | | 4–5 | Touching, in air | 0.70–0.75 | | 6–8 | Touching, in air | 0.60–0.65 | | >9 | Touching, in air | 0.50–0.55 | A derating factor is a multiplier (less than