- Reaction score
- 6,440
Re: 95 mm 4 core cable, 30 m run, in ducting under buildings backed up by 200 amp fus
hence why other de-rate factors may apply, just not for grouping as according to the marvels of calculus those two round objects never actually touch each other, do they? If you divide H / 2 by splitting it across two cables, you can't then magic some of that back over to the other one in a disproportionate way, or create H+h, the maths just doesn't allow it.
and also the temperature gradient of the cable to its surroundings.
So two touching objects, at the same temperature, won't be able to dissipate any energy from the contact area, which will lead to a temperature increase over the rest of the surface area of the objects and arguably a temperature rise in the objects themselves.
hence why other de-rate factors may apply, just not for grouping as according to the marvels of calculus those two round objects never actually touch each other, do they? If you divide H / 2 by splitting it across two cables, you can't then magic some of that back over to the other one in a disproportionate way, or create H+h, the maths just doesn't allow it.