John G wrote:

Michael A. Terrell explained on 25/05/2013 :
John G wrote:

I am surprised at all the talk about 110/220 in this thread because the
nominal in the USA has been 120/240 for some years now although there
is no guarantee that is what you get.


My line voltage has run 124.5/249 to 127/254 for over 12 years,
except during power outages. I haven't seen anything under 120/240
since the early '60s

Yes higher and not lower is my experience here in AUS but of course 245
or 250 and I am first off a 400KVA transformer for a bigger street
loop than is common off pole pigs in the US.


I prefer the US system. Less people are affected when repairs are
needed. Long drops have a single home stepdown transformer and a lot
of 'Pole pigs' are really pad mounted transformers.

All that 400 KVA feed does in increase the chances of a fire from an
arc, since the interrupt current is higher. Since the typical US home
service around here is 200A @240, your 400 KVA is little more than
double, than four the four homes on one transformer that's quite common
around here, and breakers have to be rated for 10 KA interrupt current.
I/R losses are lower at 7200V than at 240 V. That improves regulation,
and lowers distribution losses.