110v/220v Transformer

[(unknown)]

I had a question a few days ago regarding running 110v from a 220v inverter.  Thanks for all the help that was given.  Does anyone know where I can get a 110V to 220V step up (or step up/down) transformer that is not made for Europe use.  I don't know what the technical term is, but I keep getting transformer info for units that have 220V on one wire, not 110V on 2 wires (U.S. 220V).  Help me if you can.

Jimbo

[ibedonc]

you could use a microwave transfomer and rewire the sec , take it off then put one turn

on then times what you get from that with 220 and that would be the turns you need

should be 150 to 200 turns , mine was 1.2v a turn

[commanda]

Voltage is also known as "potential difference". It's the difference in potential between 2 points. You can't have voltage on one wire; it has to be referred to something.

What I think you're referring to is a transformer with 3 terminals. One marked 220, one marked 110, and a common. So there is 110 volts between common & 110; and 220 volts between common & 220. This is a single winding.

The same thing can also be had with four terminals; in this case the 2 seperate windings are isolated.

HTH.

Amanda

[Electric Ed]

I believe what you need is a transformer that can be configured as illustrated below.

They are readily available as industrial control transformers.

What kva (kilowatt) rating do you need?

(By the way, what we used to call 110/220 volts is now referred to as 120/240 volts.)

EE

[Oso]

I have never seen a transformer (or other device) that will do what you are asking.

That is, to split a single 110 source into two 110 phases with 120 degrees of seperation of the two phases. (Or split a 220 single phase into two 110 phases with 120 degrees of phase seperation.)

Perhaps someone else has, if so, I am interested in hearing about it.

Otherwise, I think you were mislead by someone who did not fully understand what you were asking.

As far as I know, you will have to go back to the idea of two 110 inverters that are piggy backed.

Oso

[ghurd]

Yea.  Anyway.  The USA uses 110, 115 and 120 interchangably.

So about a 1:2 transformer should do.  As long as everything else lines up OK.

[richhagen]

Sounds like your looking for a transformer like the diagram below which I modified from a post on an electical site.  Several manufacturers make them for converting inverter output to power 220/240 volt appliances.  I'm sure a lot of companies make them, I am aware of the Trace T240 which is a 4500 watt version.  I think they sell for $250 and up, other vendors are probably cheaper.  Google for auto transformer or Trace T240 and see if other products come up that may suit your needs.  Hope this helps some, Rich Hagen




(image modified from post by scott35 at electricical contractors.net which was posted on a forum viewable by the public)

[John II]

You also might find a transformer here that would work ?

http://www.surpluscenter.com

Click on the below to go to the transformer page

http://www.surpluscenter.com/sort.asp?UID=2004102118585660&catname=electric&keyword=EPTA

JOHN II

[drdongle]

There are commercial power transformers available for conversion of 120 to 240, 120 to 240, isolating 120 to 120 and 240 to 240 They usually have 4 windings, 2 primary and 2 secondary that can be wired in various combinations to get the desired input and output. Check with electrical suppliers such as Graybar Electric and Granger Supply.

Carpa Vigor

Dr.D

[kell]

These guys have them

http://www.allelectronics.com/cgi-bin/category.cgi?category=790&item=TC-1300&type=store

That is one of the bigger t-formers they have, go to their home page and click on transformers to see all of them.

Check out different suppliers, look for the best price for the power level you need.

[Saw Dust]

In North America our 240V is split phase.  In otherwords 120V referenced neutral on two phases with 180 deg of seperation added together(120v + 120v = 240V)  In most of europe they use 240V single phase.  In otherwords 240V referenced to neutral.  I can not think of two many applications that would not work interchangeably (although it may be a UL type safety concern)

The tongue-in-cheek way of explaining the difference is simple grab the "hot" line in 240V europe...remember how it felt.  Then come to North America and grab one of the "hot" lines in our 240V.  Compare notes and it will all become clear.

[Jerry]

Hi Jimbo

Nice visit today. Sorry bout bein slow to respond here. Didn't get out of the store till 7 tonight. Then had an armature to build for way up N in CAN.

From our conversation today I gathered your inverter is 220 volt. You got it to power your pump but would also like to power some 120v lights also.

The transformer idea is good. Several ?s are. Will the transformer like the modified sine wave or in reality square wave and what will be the total 120v load? The load ? will help you size the transformer. What other 120v loads will the transformer have?

                           JK TAS Jerry

[Nando]

Jimbo:

It is a step-down or step-up transformer, I use them continually.

I have not read what you want to do -- Please detail

You can get them from 100,250, 500 750,1000, 1500 watts and even more.

I used them on DC/AC converters with 120/120/240 capabilities for power equalization of the two 120 out of phase voltages, this way I can have 220 and 120 at the same time.

Regards

Nando

[RC in FL]

Most versatile is an isolation transformer that can be connected 120 or 240 on either side.

They can be used forward or backwards but usually there is a slight winding ratio increase to defined secondary side to make up for slight transformer loss (like 1.0 to 1.03 turns ratio)

Cheapest and smallest is autotransformer.  You get twice the power handling capability for same core size of a true isolation transformer.  Because the winding are connected in series you lose the isolation properties.

Try Allied Electronics distributor.