Quote:
Originally Posted by DavGoodlin
Good point, 120 volts does require more copper and aluminum on the LV lines. I used to think the USA, Japan and the other places with 120 volts, did not have to be as thrifty with raw materials.
I noticed that the pole lines in Europe do not normally follow secondary roads but run direct from substations to villages across field and wood. A large, square pole-mount trans in a nearby field drops to 240 -3 phase WYE and 4 wires run from there in and around the village. In a small village in Germany, it seemed to hop from house to house as if walls were utility ppoles  |
Our 120/240 volt, 3 wire wiring scheme is going to be with us for a lot longer.
The NEC mandated that no voltage higher than 120 volts to ground be present in a residence or small commercial setting, where untrained personnel would have access to the electrical system. Three phase systems would be 120/208Y.
The older electrical schemes, 120/240 delta, 240 and 480 corner grounded delta are NLA, but are supported by the POCO. Good riddence.