Soviet line voltages

On 10/13/2013 10:13 PM, Holm Tiffe wrote: Wikipedia has an interesting section on the history of various distribution frequencies: http://en.wikipedia.org/wiki/Utility_frequency#History Ineresteing that AEG managed to impose their will on all of Europe eventually--and Westinghouse in North America. I've also run into 25Hz, 60 VAC industrial equipment. While 3-phase power is available and used for US commercial installations, single-phase is used for residential, even though the high-voltage distribution is three-phase. This allows the local utility to "balance" loading, house-by-house. For example, 3-phase distribution goes to a disconnect box where my driveway meets the public road. Within the box, two of the three distribution lines are selected and continue on (as buried 6600V cables) up the driveway to the single-phase transformer sitting on a concrete pad in front of my house. The local utility people tell me that if I wanted 3-phase, I'd have to pay for a third buried line and 3-phase transformer. But 3-phase is already in place should I need it. I used to have a color monitor from Japan whose nameplate rating was 100V, 60Hz. The power plug was compatible with US receptacles. Personally, I like the idea of the old 133Hz line frequency. Less hum, smaller transformers. In our shop at work, the lighting was 220V 25Hz incandescent and was annoying--one "slow" day, I rewired the panel so that the lighting was run from 250VDC (usually used for welding). Much better! --Chuck