toller wrote:

120 plus or minus 5%.

There are many stories about where the other values come from; I haven't
heard one that sounds credible.

FWIW, here's a pointer to an "INTERIM OPINION ON EMERGENCY VOLTAGE
REDUCTION MEASURE" that
was up before the California state PUC with regards to lowering the
nominal line voltage to
117VAC during times of electrical energy shortage.

http://www.utilityregulation.com/con.../02CA13831.pdf

Makes sense that with a lower voltage the demand for power decreases.
However, this only
follows for resistive devices. Constant power loads (like motor-driven
equipment) would demand
greater current and cause increased conductor loss as well as increasing
risk of failure to
the equipment.

Dunno if they ever implemented this; at my house the voltage gyrates
quite a bit throughout the
day anyway so it's hard to tell what the "nominal" is.

later,
L