Step Down Transformers (us To Uk) Can Anyone Help?

[PlanetZany]

Hi all,
At the risk of sounding a complete clod, I thought I would enlist the help of anyone knowledgeable in these forums in the subject of step down transformers. I was thinking of buying a Marantz 2270 from a USA dealer. I'd be so grateful if anyone here might give me a guideline as to which step up transformer I would need to buy to enable me to use it in the UK? The only other transformer available to buy is the second one below, which doesn't give ampage.
I may also wish to run more than one Marantz receiver. I have no idea of the ampage or wattage though!
_______________________________________
HEAVY DUTY 240V TO 110V CONVERTER FOR LARGER LOADS
STEP DOWN TRANSFORMER
1000 watts, 8.30 Amps
1500 watts 12.5 Amps
2000 watts 16.6 Amps
3000 watts 25 Amps
_______________________________________
240V TO 110V CONVERTER 100 TO 300 WATTS
STEP DOWN TRANSFORMER
300 watts
500 watts

So grateful for any help anyone can give here.
From a very "novice" novice!

 

[Hyperion]

Apparently the "rule-of-thumb" for this is to double the maximum wattage your US device is expected to use - and then buy a transformer to suit, you want a step-down transformer. You can see this wattage on the rating plate of the unit requiring power - usually on the rear panel of the unit - difficult I know, as you do not have sight of it yet? - remember bigger (transformer) wattage is better.

To explain
You read - UK mains socket (240v) -> Transformer 240v in -> 120v out -> Marantz - in other words Step Down.

At this point I will 'step down' and let possibly more knowledgable folk give you further advice on this. - like where to get one from?... try Googling it?

Welcome to AK - as I see you are very new here ..... Oh, and try not to double post - confuses the hell out of everybody.

John

 

[PlanetZany]

Cheers...

Hi John, thanks for the info, sorry for the posting confusion!

Yeah, something about counting amperage by dividing the wattage by the voltage ...

1500 w divided by 240 v = 6.25A

A case of the bigger the amperage, the better?

 

[Valsimot]

If you do buy it in a store, see if you can't test before you buy. Some of them can hum pretty badly.
Like Hyperion said, read the wattage usage off the back of your new marantz and buy a step down puts out at least double that. I don't think you'll need more then 1000w, but who knows, you just might get something else that is US that you want to use with your new receiver.

 

[westend]

2270= 500w. max at 110 v..

 

[BrocLuno]

Wattage is voltage x amperage. UK 240 volt mains are there because they don't want to have to push so many amps to get the same power (wattage). USA mains are 120 'cause we don't care )) and we established the format more than a century ago.

The USA receivers will draw XYZ watts at 120 volts. When converted, they whole load will be the original power requirements plus conversion losses and line losses. One thing you can do is ask an AK'er who has the same model to put one of those inexpensive digital load monitor meters on their machine at the wall plug and then crank it up driving a real load to see if there are discrepancies? The transformer will have to handle peak loads plus aging parts like slightly leaky caps and such. That's why the recommendations for double the rated power (wattage) requirements. In either system, watts is watts. So if you go by power requirements, you'll be OK.

Next question, are you using a UK turntable or tape deck? Will there be any ground loop issues? Neutral is still the same on both systems and I hope you'all have a dedicated ground in the UK system? That is, a three pronged plug? If so, you should be OK. The deLux solution is a power conditioner with both 120 and 240 VAC output. That puts all the bits on a common supply system and takes care of any possible ground or polarity conflicts

Something like this might be appropriate: http://www.carebase.com/Dual-voltag...230vac-ouput-2kVA-ILc-2000-VRp-Dual-Range.htm