110V ac

The Corcom power inlet/fuze/emi filter things we buy used to be marked

100-120-220-240, with a little selector thing that switches transformer taps. One day they started arriving labeled 100-120-230-240, even though nothing else had changed. Given the way the transformer taps have to work, this isn't right.

I guess some bureaucrat in Brussels decided that 220=230.

John

Urban Legend:

Except for the states (Oregon included) where you calculate the board-feet of a log coming out of a state forest using area = 3/4 * diameter^2, i.e. pi = 3. This is _not_ done because of religious conviction, but to make the 'rithmatic easy.

This was related to me by a fellow who made log scaling computers. He was off testing one (complete with pi = 3 software) in Roseburg when a truck pulls up to the log scaling station. The old guy running the place glances at the load and names a figure in board feet. Kevin thinks "lazy old crank" to himself and goes off to measure logs. 10 minutes later his computer agrees with the old guy to within 5%.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Hey, cool:

Think maybe I should get back to work?

John

You might find it amusing that in Hollywood, some video/audio houses use 120 center tapped for the equipment. It seems all those Corcom filters with 1000 pF caps from neutral and hot to ground can throw in some significant imbalances into the neutral causing hum all over the place. The 1 big transformer is easier than opening hundreds of units to rework/replace those line filters. Of course the down side is requiring dual breakers (common actuator) and twice the wiring. GG

We spec'd it to operate at 240+-10%, 50/60 Hz, which calculates to

264. If only people would read specs!

Here we have residential 120-0-120 power. In my old house, a 100+ year-old Victorian, we had an intermittent open neutral (that's the 0v line in the middle) out on the pole outside. That caused interesting effects, as about half the 120-volt devices in the house were then operating in series with the other half, off 240 volts.

John

Are there any 'standards' - de facto or actual - that define what is meant by a 110V (mains) supply in the UK and throughout Europe in the same way that the pan-European household mains supply is defined?

Thanks in anticipation.

I don't think anywhere in Europe uses 110V for mains, it is all a nominal

230V (By international agreement (actually by eurofudge)). The only place I see 110V over here is on building sites where it is usually 55-0-55 with an earthed centre tap. Note that as neither side of this supply is earthed, you need to fuse both lines if splitting a high current '110v' supply down for smaller loads. Rather like what is required when running 230V (or 208V...) appliances in the 'states.

There is a standard for the transformers used to produce this on building sites but I cannot remember the number.

HTH.

Regards, Dan.

"John Larkin" schreef in bericht news: snipped-for-privacy@4ax.com...

FAIK that's correct although it was not one bureaucrat but a bunch of them. Mains voltage should be brought to 230V all over Europe. The UK did so already by increasing tolerances. The voltage itself did not change. In other countries the voltage is increased over time and most equipment is rated for 220/230V thes days.

petrus bitbyter

Hello John,

We had our fair share as well. Remember the old law from, I believe, the state of Indiana that declared that the value of Pi is 4? At least they didn't repeal Ohm's law or declare it unconstitutional.

Regards, Joerg

There isn't any 110V ac in Europe out of a wall socket.

Construction sites use safety isolation transformers for power tools that are

110V centre tapped to ground ( 55-0-55 ) for elimination of shock hazard reasons but that's quite specialist and not relevant to the nomal mains supply.

Graham

Yes

Yes

It beats being electrocuted.

Also less likelihood of pilfering tools to 'take home' ! :-)

The market is way big enough to support the standard.

Graham

They actually decided that 220V +/- 6% and 240V ( UK ) +/- 6% was covered by

230V +/- 10 % !

Some of the wealthier ( better infrastructure ) mainland European countries have actually now really changed from 220V to 230V.

In the UK we're still 240V and the light loading of the supply caused by the elimination of manufacturing industry often means that the real voltage at the socket can regularly reach 250V ! 243V is more common most places though.

This means getting the right incandescent bulb ( Europe wide ) that doesn't burn out or give a dim light quite fun. 220 -230 and 240 V versions are on sale according to locality.

Oh - you ought to bear this in mind for your toroidal transformer. It shouldn't saturate at 50Hz and 253V.

Graham

For a variety of reason - all mainly associated with leakage currents - quite a few really pro recording studios run their ac supply centre tapped. Old guitar amps are supposedly one of the worst offenders aside from currents resulting from line filters.

Graham

Well, since the US uses 110 (or 120 or 117) maybe they can also sell such tools in the US market. Maybe that is why so many high-end US power tools have removeable cords?

--Mac

110V supply is common in industrial plant in the UK. As it's over 50V, the normal IEE Wiring Regulations apply, and you can use any of the earthing schemes covered therein as appropriate. Don't forget that the current is twice normal, so size conductors accordingly.

I've always assumed the reason was to stop the workforce walking off with the company's power tools.

Paul Burke

I read in sci.electronics.design that Tim Wescott wrote (in ) about '110V ac', on Tue, 8 Feb 2005:

Not only building sites. Open-air markets as well.

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I read in sci.electronics.design that John Larkin wrote (in ) about '110V ac', on Tue, 8 Feb 2005:

Not quite; they played games with the tolerances:

220 V: -6% + 10%, i.e. 207 to 242 V 230 V: +/- 10% (now: there was an earlier fudge) i.e. 207 V to 253 V 240 V: -10% +6%, i.e. 216 to 254 V

So most 220 V and 240 V supplies are within the 230 V tolerance range.

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

[snip] [snip]

The typical arrangement in my neighborhood is one transformer per two houses, and everything is underground so as to not sully the view.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

I read in sci.electronics.design that Tim Wescott wrote (in ) about '110V ac', on Tue, 8 Feb 2005:

It allows for wastage.

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk