Thanks but this topic is about DERATING NOT VOLTAGE DROP.
Though somewhat off topic, less voltage drop means that there's less waste heat lost in the wiring. And thus the wires won't get as hot. So you use heavier conductors in situations where many wires are bunched up together. Each wire contributes less waste heat then they would have if smaller given the same loads. Derating also gives a side benefit of less voltage drop for the customer/user.
[This message has been edited by wa2ise (edited 03-18-2005).]
