Cable Rating And Derating Factor

If the load requires 100 Amps, we cannot use the 100A cable. We must select a larger cable. Required Standard Rating = $\frac\textLoad CurrentF_total$ $$\textRequired Rating = \frac1000.517 \approx 193 \text Amps$$

If your real-world environment deviates from these, cable rating and derating factor

Real-world installations rarely match these perfect laboratory conditions. This is where derating becomes necessary. If the load requires 100 Amps, we cannot use the 100A cable

The NEC uses a formula based on conductor temperature rating. This is where derating becomes necessary

We must select a larger base cable. Iterate until $I_actual > 150A$.

If you'd like to calculate a specific load, I can help you determine the corrected cable size: What is your in Amps? What is the ambient temperature ? How many other cables are running alongside it?

We would need to select a cable rated for roughly 195-200 Amps in standard conditions to carry the actual 100 Amp load safely.