Step-down transformer question...

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Sorry if this is in an inappropriate forum, but there isn't really an electronics forum :S

Anyway:

What happens if you use a piece of US equipment with a Step-Down Transformer (220-110v) that is above the max wattage rating of the transformer?

I ask because I have a Poweramp from the USA and it is rated 500w but don't have a transformer of 500w or greater - I have one that is less... what would happen if I used it? Would there just be not enough power getting to the Poweramp? Or worse... ?

Many thanks overclockers!
 
Docaroo said:
Sorry if this is in an inappropriate forum, but there isn't really an electronics forum :S

Anyway:

What happens if you use a piece of US equipment with a Step-Down Transformer (220-110v) that is above the max wattage rating of the transformer?

I ask because I have a Poweramp from the USA and it is rated 500w but don't have a transformer of 500w or greater - I have one that is less... what would happen if I used it? Would there just be not enough power getting to the Poweramp? Or worse... ?

Many thanks overclockers!


At best it will work fine.

At worst it will explode/catch fire, killing you, your family, your pets, your neighbours, and end all life on earth as we know it.
 
The simplest/neatest solution may be to replace the transformer in the amplifier to a UK primary one. That is providing it will be staying here and you think your able to do it. Possible the transformer has twin primaries as it is, in which case re-wiring the primaries from parallel to series will make it suitable for UK use. You could get a repair shop to do it i'm sure if you don't fancy messing with mains wiring :)
 
Hey DrEm... ok here's more details:

It is a Peavey Classic 50/50 Tube Stereo Preamp - each side runs at 50w tube power - the power rating is 110v, 60hrz, 500w...

It will be in the UK permanently, so any extra help/advice changing transformers is much obliged!! Where do I start hehe? Where can I get a UK transformer for the Poweramp internals??

Thanks guys! - PS I found my old transformer, its 400w but really old and I wouldn't trust it anyway haha!
 
Ah, it's a tube amp. I assumed it would be a transistor one. Its not impossible to do nonetheless, but they arn't something I know much about. You might try over on this forum;

http://www.electro-tech-online.com/

But you'd have to explain in some detail unless someone happens to know about that specific model. Sorry, I hoped it was just a toroidal one where a replacement can be quite straightforward.
 
You're going to need a step-down transformer that can handle the wattage. A tube amp will use the 110VAC direct for the heating elements in the tubes.

You might also get some funny low-pitch humming out of it due to 50Hz/60Hz differences.

One way you could do it is to get a US uninteruptable power supply (battery backup) that does both 220V and 110V outputs. They normally plug into 220 to begin with and then you'd have your 110V at the correct frequency and voltage all in one.

Mind you, they can get a little pricey, especially with shipping.
 
Here is the first listing I could find. The top two do what I was talking about with the 220V (230 in this case) input and 110V output. But at just shy of $800 plus shipping, as I said they ain't cheap!! :eek:

But this way you know what you're looking for actually exists and have a part number for those "Hey, I'm looking for an inexpensive version of [part #], got any ideas?" questions you might ask around with.....
 
Mickey_D said:
They normally plug into 220 to begin with

What sort of nominal voltage range are they built to handle tho? In this country the voltage is allowed to be 230v +10% -6% Which gives a range of 216v-253v , normally though you'll find it around 240v (because that used to be our voltage pre '95 and in practice very little has changed!)
 
Well, according to the spec sheet found here they can handle up to 242V input. That's just that one. There's got to be one out there designed for just what the OP is trying to do though, and within a reasonable budget.....
 
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