# Transformer required



## loddy (Feb 12, 2007)

Hi Guys

I am looking for a transformer, 230 volt 50 hertz to 120 volts 60 hertz that can handle about 7 kw. I have searched and searched the web and have found one, but at £1800.00 seems a little steep.
Can anyone help ?

Loddy :wink:


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## cabby (May 14, 2005)

have you tried one of those RV converter dealers, or even look on the RV owners club site for info.

cabby


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## cabby (May 14, 2005)

have a look at these.

http://www.airlinktransformers.com/stepupstepdown-transformers.asp

cabby


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## pippin (Nov 15, 2007)

Remember that if you stuff 50Hz into one side of a transformer you will still get 50Hz out the other side, no matter what the voltages involved may be.

A transformer to handle that load will be massive and very, very heavy and totally unsuited for MH use.

It might help us to know why you want a transformer to handle that amount of power.


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## raynipper (Aug 4, 2008)

loddy said:


> Hi Guys
> 
> I am looking for a transformer, 230 volt 50 hertz to 120 volts 60 hertz that can handle about 7 kw. I have searched and searched the web and have found one, but at £1800.00 seems a little steep.
> Can anyone help ? Loddy :wink:


Hi Loddy.
I have a 240v to 120v. 5.5 kw. transformer I could sell you for £70. But it's here in France.

I bought two about 10 years ago and used one on my imported Eagle. Worked well with no overheating or hum. Quite heavy as I can only just carry it.

Let me know if you are ever heading this way. Will send pics if you want.

Ray.


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## Photag (May 27, 2008)

May have one that size. How quickly do you need it and could you pick up from the Cotswolds. What will you be using it for?


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## loddy (Feb 12, 2007)

The one I have found is 300mm cubed and comes in at 23 kg, I need it to run RV electrics and the important bit is 60hertz. I know people use builders transformers and such like 8O but on a new RV with power management systems I do not,

Loddy 

See www.RV transformers


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## Photag (May 27, 2008)

That link does not work! Regardless, the laws of physics are such that you cannot change 50 herz to 60 herz by a transformer. Still not sure why you would need 60 herz.


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## rayc (Jun 3, 2008)

This is a previous topic which may have some relavence.

http://www.motorhomefacts.com/ftopict-79777-.html

As it has been said a transformer will not convert the frequency but you can get a combined transformer / frequency converter. They are not cheap and for 7000w will be very heavy.


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## loddy (Feb 12, 2007)

I haven't posted a link but if you search rv transformers you will see what I am blabering about, and you can convert 50 to 60 hertz and it does make a difference

Loddy


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## rayc (Jun 3, 2008)

loddy said:


> I haven't posted a link but if you search rv transformers you will see what I am blabering about, and you can convert 50 to 60 hertz and it does make a difference
> 
> Loddy


http://www.rvtransformers.co.uk/index.html

Googling as you suggested found the above link.
It is not a straightforward transformer. It is a Frequency Converter - Voltage Stabilizer - Static Variable Transformer, according to them.

Very sophisticated - and expensive no doubt as it looks a well designed professional bit of kit. Looks like a RV forum is the place to get further info as it is a specialised requirement .


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## gromett (May 9, 2005)

If none of the other peoples transformers are suitable have a word with Louth Transformers. They make them in anything from 1VA up to national grid size.

A transformer as stated cannot change the fequency of the supply you will require additional equipment to do that.

Cheers
Karl


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## pippin (Nov 15, 2007)

The RV tranfsormer website is a bit scaremongering!

I would be asking first of all whether it produces a pure sinewave or a stepped squarewave.

It is just a glorified inverter after all!


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## olley (May 1, 2005)

Hi this was being flogged a year or two back, he reckoned he had one made specially for himself and then decided to sell them. Price was around £1800 I believe. http://www.rvtransformers.co.uk/

It is a voltage converter/phase changer/voltage stabiliser all in one, nice bit of kit but £1800!! He claims that having the wrong Hz will cause multitudes of problems, which is a slight overstament :lol:

The only thing I know which definitely doesn't like the wrong Hz is the yank microwave, they work but they don't like it up-em. The AC is slightly down, lights, heaters etc are unaffected.

Olley

PS if I won the lotto I would buy one as I like my toyzs :lol:


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## Patrick_Phillips (Aug 17, 2006)

pippin said:


> I would be asking first of all whether it produces a pure sinewave or a stepped squarewave.


C'mon, Pippi, get with the program. We call it modified sinewave nowadays - much sexier sound to it. Still the same shaped waveform though :evil:

Shouldn't we be mentioning that the OP should be looking for an inverter not a transformer? 

Patrick


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## olley (May 1, 2005)

Patrick_Phillips said:


> Shouldn't we be mentioning that the OP should be looking for an inverter not a transformer?
> 
> Patrick


NO an inverter unless its huge won't run my two AC units together, my 1800watt inverter won't even run one. So its a cheap tranny, and you can reverse feed it to get 230v from the genny. Can't do that with an inverter.

Olley


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## Patrick_Phillips (Aug 17, 2006)

olley said:


> NO an inverter unless its huge won't run my two AC units together, my 1800watt inverter won't even run one. So its a cheap tranny, and you can reverse feed it to get 230v from the genny. Can't do that with an inverter.
> Olley


Not clear about what you are trying to do, really, but if you want to go from 230v 50Hz to 115v 60 Hz then the device you need is an inverter and you can get these rated at 7kw for about £600 new.
True, you cant get 230v 50 Hz by feeding it with 115v 60 Hz but that would need another inverter.

The point I was trying to make is that if you search for a transformer you will not be offered anything that converts the cycles. Search for an inverter and you will.

Regards
Patrick


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## loddy (Feb 12, 2007)

loddy said:


> The one I have found is 300mm cubed and comes in at 23 kg, I need it to run RV electrics and the important bit is 60hertz. I know people use builders transformers and such like 8O but on a new RV with power management systems I do not,
> 
> Loddy
> 
> See www.RV transformers


What i am trying to do is in a previous post

Loddy


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## olley (May 1, 2005)

Patrick_Phillips said:


> The point I was trying to make is that if you search for a transformer you will not be offered anything that converts the cycles. Search for an inverter and you will.
> 
> Regards
> Patrick


Hi Patrick, I think Loddy's going over the top, but its his money. 99% of all Rv's converted to UK spec. if done properly use a proper tranny. You could as you say use two inverters, but that's an expensive and imho complicated solution to a problem which doesn't really exist. ie Hz.

Loddy your power management system is 110v not 230v, to get it to manage your 230v as well you will need to convert all your power to 110v and then convert it back to 230v utilising a 110v feed which is after the PM.

I have looked at doing this myself, but can't see any real benefit, as it involves me fitting another tranny.

Olley


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## loddy (Feb 12, 2007)

Olley
Take one RV ( all power is 110 volt) bring it to the UK , install one device to convert UK power to USA power keeping all the power requirement at 110 volt,
to me that is simpler than installing a 230 volt ring main and devices to split 230 and 120 and make all the compressors, washing machine and microwave struggle with the wrong hertz

Simple or am I being thick (think not) don't forget we are dealing with USA 230volt 50 amp (2 lives 1 neutral )

Loddy


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## olley (May 1, 2005)

Hi Loddy some RV's do stick to the 110v and not bother with a 230v ring, but I bet that effects the resale value, as most people want 230v somewhere in the RV, and not just a little plug in converter for phones etc.

Your right about the yanks using 230v x 50amp, but you won't get that here, the max you will get on any euro campsite is 16amps, so around 32amps at 110v, so any tranny/converter much over 3300watts is a waste of money.

As for your appliances struggling, bit of an overstatement I feel, I have never noticed any difference running the AC on EHU or the genny, both kept the interior nice and cool abroad. Don't have a W/M but the only problem there could be the modified sine wave I believe.

Just my thoughts, its a nice bit of kit their flogging, and I do like my toyzs, but is it necessary? looking at the amount of RV's running around this country now with few problems, I doubt it. 

But then again half the toyz's I bought for mine weren't necessary. :lol: 

Olley


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## raynipper (Aug 4, 2008)

Beware Loddy.
The American 240 volt is centre tapped neutral. i.e. 110v higher and the other 110v lower than neutral.

I have converted several US RVs to 240 and as you say it's very possible to just bung in a transformer to feed all the 110v appliances and add some 240v outlets off the primary.

But when you have a generator is when it gets very complicated with switch over relays.

Often there are two or even three legs of 110v outlets. Sometimes you can just lift one or even two of these legs feeding the 110v outlets, change those outlets to UK 13a. and reconnect them again to the 240v primary of the trans.

The only things to be affected by the different frequency will be clocks, the microwave and air con but you should not notice it. Sometimes the 'converter/charger' might hum a little.

Ray.


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