Interesting discussion going on here. Most of Europe is standardised to 230 / 400 Volts.
I know of some older cities in The Netherlands where still some 127 / 220 Volts ( 120 ° phase shift) networks was in place ( Dordrecht, Leiden, Amsterdam ) about 20 years ago, I have worked on them because i done a rewire by a family member.
The 127 Volts is rarely used but 130 Volts lightbulbs there seem to last forever.
The power points were ran at 220 V Ø to Ø, and the lighting at 127 V between phase and neutral.

These systems were gradually phased out to 220 / 380 and now 230 / 400 Volts at 50 Hz.

O.T. In remote parts of Italy there are 150 - 160 / 275 Volts networks in place. Occasionally there are old lightbulbs and kWh meters for sale on Ebay Italy.
Then I own one of the Italian distrubution networks books where these systems are described in detail.

But for above thread. Get a 240 / 110 Volts transformer (safest). or buy a charger with the required low voltage output to charge your batteries ( Jaycars)

He sais he lives in Adelaide where the mains voltage is at least 240 V and may even be 250 V.

edited for typo's

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Umm you get 415V from two phase over here.

And I thought it was 120 degrees for two phase ?

 

Wait a minute.
330W to charge a little battery? No way, man!
The 3A is probably the OUTPUT of the lttle 110V charger, not its input.

The voltage output of the charger times 3A and then double it would be the power required from a small auto-transformer for it.

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As 360 degree rotation is a single phase (a sinusoid), if you wanted a second balanced phase than it would be 180 degrees apart from the first - if it was only 90 degrees apart it would be a very unbalanced system.

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It's understandable how to came to that assumption but it's incorrect.

A split phase system

http://en.wikipedia.org/wiki/Split_phase

A two phase system
There's no fancy picture here but I'll offer two simple quotes:
"Two-phase electrical power was an early 20th century polyphase alternating current electric power distribution system. Two circuits, or "phases", were used, with voltages 90 electrical degrees apart in time."
---snip----
"Three-wire, 120/240 volt single phase power used in the USA and Canada is sometimes incorrectly called "two-phase". The proper term is split phase or 3-wire single-phase."
http://en.wikipedia.org/wiki/Two_phase

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I see what you mean, you're telling us about a system used in 1895! - does this have any relevence in the 21st century?.

As for the American system being incorrectly called 'two phase', I would have thought it's a better, more sensible, name for it - and makes more sense than reserving the name for a long obselete system?. I'm presuming they don't still use that antiquated system for driving motors anywhere?.

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I don't know.

The term split phase makes perfect sense to me - it's a single phase split by a centre tapped transformer.

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By two phase, I ment if you take a three phase supply and connect across two of the phases. It is unbalanced but you have about 415V. I've always known that as two phase anyway, it's used in some factories.

 

That should really upset the electricity board!

Presumably it's been specifically installed for that use, with a solid neutral?, which you wouldn't normally have.

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I've seen them used in dairy farms where full three phase with neutral is available. The three phase is used through a star-delta timer to drive the main milk separator while the two phase motors are used in small(ish) pumps.

I guess it's to reduce the cost of the motor. I've never really asked why, I was just helping my dad build the controllers.

Looking at a graph of a three phase sine wave, two phase should give a peek voltage of about 75% of the full peek voltage.

 

That, is (as you say) two phases of a three phase supply.

Normally you use a three phase plug but only use two of the pin and as Nigel says, the electricity company won't happy if you draw huge loads from one or two phases, there again it's just as likely that someone else is drawing just as much power from other phases to roughly ballance it out.

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Peak has an 'a' in it

Peek is entirely different, although you might 'peek' at a milk maid.

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English language was never my strong point.

 

The two phase system (90º) is used in some (AC) servo motors: One phase is allways "on" while the other one varies its voltage from "full foward" thru cero to "full reverse".

Of course, to obtain the "foward" (0º) and the "reverse" (180º) voltages they use a split phase transformer - even a variable one ("Variac") to regulate the voltage (and phase).

The 90º phase can be obtained (from a three phase system) with some exotic connections: for example if you take one phase (0º - 180º) between two of the 3 phases, between the third phase and the neutral you have 90º.

Of course, it's only a means to drive the motor. a two phase motor (90º) is a polyphase motor (like a 3 phase one).

With an split phase supply (180º) you have to use a single phase motor. A single phase (induction) motor needs some auxiliar starting system (2nd winding, capacitor, shadow pole, etc)

Power distribution is allways a three phase system. (with or without a "star centre" neutral) or, for short distances and small loads, a single phase system (or may be split phase).

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The system Hero999 describes is also used a lot in rural New Zealand.

From the 3 phase line a 2 phase transformer with secondairies of 2 x 230 Volts or 2 x 240 Volts is used with the windings in parallel.

With the windings in series 460 or 480 Volts can be taken off for a 1 Ø motor with an extrernal capacitor to create the phaseshift.

In the second case the neutral will be on the link between the secondairies to keep the phase to neutral; voltages below 250 Volts.

This set up is also used on the SWER systems which have only a 1 phase line fed from an isolating TX at a voltage of 6.6 or 11 kV.

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Electricity, Electric clocks, Meters and Trains are great.