SCA is a major factor with larger conductors. So is the Skin effect.
Say, Scott, the way I took the question was hypothetically wiring a house using #10, #8, or even #6 on 20 A circuits.
1. Even if 2/0 were used, I don't see skin effect coming into play. Is skin effect dependent on the current being carried? I thought it was dependent on frequency and conductor resistance and acted to limit current.
2. To me, 2/0 is all skin at 60 Hz.
If an arc fault is a much higher frequency, then that might limit it. Is this actually an issue?
3. The voltage drop will be lessened by using the larger conductors. This makes larger conductors sound advantageous.
4. I would like to hear more about what happens when the circuit is shorted. This makes larger conductors sound disadvantageous. Is there a prohibition or advisory against using ungrounded conductors which are significantly over capacity for the length of the run and the rating of the branch?
5. Is a short circuit on #6 significantly more dangerous than with #12 given that the OPD is a 20 A CB?
6. How about comparing short circuits in 8-2-G (120 V) to that in 10-3-G (240 V)?
These are some cases where I would rather ask you than trust my intuition.
