How to change a 220vac single phase out put to a 220 split phase

Lapeart

I have a inverter with has a 220 single output but my house uses 220 split phase

inetdog

Re: How to change a 220vac single phase out put to a 220 split phase

Lapeart wrote: »

I have a inverter with has a 220 single output but my house uses 220 split phase

You can get a transformer which will do this. The primary will be 240V and the secondary will be 240 with a center tap to provide 120/240 single phase three wire (not counting safety ground). In some cases, if neither side of the inverter output is grounded, you can use an autotransformer to reduce the cost. I believe that Outback, among others, offers such a transformer and it is expensive but very rugged.

BB.

Re: How to change a 220vac single phase out put to a 220 split phase

A couple of things to think about...

Many 220 VAC inverters are 50 Hz, not the North American standard of 60 Hz... What is your inverter's output vs what is your needs?

Inverters should be sized to your loads... Peak Watts, average watts, starting surges, etc. Too large of AC inverter, you may have 20-40+ watts of losses just turning the inverter on.

Your battery bank should also be sized to your loads (and how much charging current/energy you can get per day). Too large or too small of battery bank will cause problems.

Adding a transformer to change from 220 VAC to 110 VAC can waste upwards of 5% of your power usage. And if you have 50 Hz inverter, you have to find a 50 Hz transformer (or derate your 60 Hz transformer).

-Bill

inetdog

Re: How to change a 220vac single phase out put to a 220 split phase

BB. wrote: »

And if you have 50 Hz inverter, you have to find a 50 Hz transformer (or derate your 60 Hz transformer).

If the transformer is limited by core saturation, you will have to reduce the input voltage to use 50 Hz, not just reduce the available power handling capacity.

A 240V 60Hz transformer cannot in general be used with 240V 50Hz. But it can be used with 200V 50Hz.

Cariboocoot

Re: How to change a 220vac single phase out put to a 220 split phase

inetdog wrote: »

If the transformer is limited by core saturation, you will have to reduce the input voltage to use 50 Hz, not just reduce the available power handling capacity.

A 240V 60Hz transformer cannot in general be used with 240V 50Hz. But it can be used with 200V 50Hz.

Of course the 50 Hz Voltage 'standard' is 230 and quite often lower (as per the 220 rating the OP used).

In reality you can indeed use a 240 VAC 60 Hz transformer with 230 VAC 50 Hz. It's not very efficient and the power rating must be lowered as Bill said. You will lose not only the 4-5% the transformer consumes but an additional 12% minimum in power capacity. Most people will never notice this on account of not running near the peak of the transformer's capacity. That helps a lot.

inetdog

Re: How to change a 220vac single phase out put to a 220 split phase

Cariboocoot wrote: »

Of course the 50 Hz Voltage 'standard' is 230 and quite often lower (as per the 220 rating the OP used).

In reality you can indeed use a 240 VAC 60 Hz transformer with 230 VAC 50 Hz. It's not very efficient and the power rating must be lowered as Bill said. You will lose not only the 4-5% the transformer consumes but an additional 12% minimum in power capacity. Most people will never notice this on account of not running near the peak of the transformer's capacity. That helps a lot.

At 50Hz instead of 60Hz, the magnetizing current, and therefore the peak magnetic field, in the transformer core will be 6/5, 120%, of the current the transformer was designed for. The extra magnetizing current will cause greater I²R losses than designed. This will produce higher than normal zero load losses and will reduce the total current capacity and therefore the total load power capability of the transformer. All of this supports your point.

But a separate issue the 20% greater magnetic field can put the transformer at or beyond the saturation flux of the iron core. If this happens, the current can run to six or more times the design current because the inductance of an air coil is much lower than the inductance of an iron cored coil. It is this non-linear and very large current that I am concerned about.
The effect on the core would be the same as running the transformer with 290V 60Hz on the primary instead of 240V 60Hz. Not many transformers are designed that conservatively and I would not risk it without checking with the manufacturer of the transformer in question.

(The saturation of a transformer is related to the V/f ratio of the applied voltage. Check this out on the Mike Holt Forum if you are not convinced.)

Cariboocoot

Re: How to change a 220vac single phase out put to a 220 split phase

In the real world it works for exactly the reasons I mentioned.

It just isn't great.

inetdog

Re: How to change a 220vac single phase out put to a 220 split phase

Cariboocoot wrote: »

In the real world it works for exactly the reasons I mentioned.

It just isn't great.

All that I am saying is that it may work for all of the transformers that you have tried, but that does not mean it will work for all transformers. And if it does not work, the consequences for the transformer will be catastrophic.

Cariboocoot

Re: How to change a 220vac single phase out put to a 220 split phase

inetdog wrote: »

All that I am saying is that it may work for all of the transformers that you have tried, but that does not mean it will work for all transformers. And if it does not work, the consequences for the transformer will be catastrophic.

Don't buy junk.
Know what you are buying.
Problem solved.

inetdog

Re: How to change a 220vac single phase out put to a 220 split phase

Cariboocoot wrote: »

Don't buy junk.
Know what you are buying.
Problem solved.

Always buy 130V light bulbs, because the line voltage may go above 120V sometimes.
Different problem solved.

Cariboocoot

Re: How to change a 220vac single phase out put to a 220 split phase

inetdog wrote: »

Always buy 130V light bulbs, because the line voltage may go above 120V sometimes.
Different problem solved.

Well I've had a 150 VAC line meter fry from grid Voltage surge so your "130 Volt" bulbs may not always save you. No matter how many problems you think you've got covered, someone always dreams up a new one.

The company I worked for built, among many other things, transformers. Never did one of them get dumped on my desk with the "tell us why this failed" question (that was my job; analyze device failures). They were quite robust and could take enormous amounts of abuse. I would not be at all surprised to find "overseas" autotransformers these days rated as "4kW" which would cook at 3: seems they rated things on a basis of <1 sec application.

So if you have 50 Hz power the best choice is to get a 50 Hz transformer. The second best is to get a good quality 60 Hz unit and understand that you need to derate it 20% and that it will run hotter, shorter, and buzzier.

BB.

Re: How to change a 220vac single phase out put to a 220 split phase

And slow down here a bit... The orginal poster has yet to return.

I was guessing that he may have a 50 Hz 220 VAC inverter (220 VAC native output inverters are not very common in the US)--I do not know.

-Bill

Lapeart

Re: How to change a 220vac single phase out put to a 220 split phase

ok i just our the outback auto transformer. anyone have a wiring diagram to configure this

Lapeart

Re: How to change a 220vac single phase out put to a 220 split phase

the inverter is 220 60hz. it a Canadian box

Cariboocoot

Re: How to change a 220vac single phase out put to a 220 split phase

Lapeart wrote: »

the inverter is 220 60hz. it a Canadian box

In that case we've been discussing the wrong thing. No problem getting split phase 220 VAC from that using a standard autotransformer.

The wiring is simple. Transformer has four connections: L1, L2, N1, and N2. The two Neutrals are connected together (and usually grounded). L1 and L2 go to the inverter output @ 220 Volts. 110 VAC will be available from Neutral and either L1 or L2.

What inverter is this, exactly? The power standard here in Canada is 240 VAC 60 Hz, the same as in the USA. We sent little red trucks out to change everyone's motors back in the 1950's and switch from 220 VAC 50 Hz then. No, seriously; we did.

BTW over the years the 'standard' Voltage in North America has been listed as 220 and 240 (with household Voltage being 110, 115, 117, 120, 125, 127 et cetera) and they are usually interchangeable.

Europe has 'adopted' 230 VAC 50 Hz as standard by broadening the acceptable range of Voltage. I think it's -6%/+10% or a range of 216 to 253. Pretty wide range.

BB.

Re: How to change a 220vac single phase out put to a 220 split phase

Outback has a nice set of manuals/application notes:

http://www.outbackpower.com/outback-products/integration-hardware/item/autotransformer

-Bill