On Dec 27, 2:29*pm, terry wrote:
On Dec 27, 10:37*am, (Doug Miller) wrote:





In article , wrote:
On Sun, 27 Dec 2009 03:24:59 GMT, (Doug Miller)
wrote:

In article ,
wrote:
On Sun, 27 Dec 2009 00:40:52 GMT, (Doug Miller)
wrote:

BTW -- it hasn't been 220/110 in the United States for a loooooong time.
It's
been 240/120 for at least the last 25 or 30 years.

Actually you are wrong too. It is by definition 115/230 and in reality
USUALLY from 115 to 117 per side.

Guess again.

http://en.wikipedia.org/wiki/Mains_p...ound_the_world

lists both Canada and the U.S. as 120/240.
Well, I monitor the voltage on my home office power as well as at a
customer site and it is very consistent at 115-117 volts at both
sites. Has been for years. *This is in urban Waterloo Ontario and
Kitchener Ontario.

And what comes into your house must there be the standard. :-)

Also virtually every motor or electrical device sold in North America
for residential use is rated at 115 or 230 volts.

Not true.

A quick random sample of half a dozen of my portable power tools and kitchen
appliances shows five marked "120V" and one marked "120V only". In fact, the
only thing I could find in the house that's marked for 115 is an electric
clock that to my certain knowledge is _at least_ forty years old.

In industrial and large multi unit residential applications with 3
phase power it is 120/208. Virtually everywhere else in Ontario, at
least, it is 115/230 single phase.

And therefore it's the same everywhere?- Hide quoted text -

- Show quoted text -

What are the USA and Canadian limits for voltage variation from a
nominal of say 117 volts?

For exam[ple:
Using 117v as a base;
Minus 5% *= 111.15 (say 112v RMS)
Plus *10% *= 128.70 (say 129v RMS)

And as mentioned in some installations the higher voltage can be
either 230/115 volt (Usually domestically) or 208/115 *(most likely
commercially and/or from 3 phase supply).

We have electric baseboard heaters that came, marked; 1200 watts at
230 volts, *970 watts at 208 volts. (The V squared divided by R = W
thing)- Hide quoted text -

- Show quoted text -

BTW. Further to this discussion about higher mains supply voltages and
permissible limits for variations these days; the topic has come up
often in another news group that deals with vintage radio restoration
etc.
The more consistently higher voltages these days can have an impact on
older radios that were operated back when on, say 115 volts or less.
But which today often face 120 or higher.
Again (for simplicity) doing the V squared business, the difference
between say 113 volts and say 120 volts is almost a 13% increase (plus
one sixth!) in power and therefore additional heat within an old
radio.
The radio restorers therefore use their expertise and various means to
either further protect (extra fuses etc) and/or to reduce voltage to
protect the older equipment components.