# Help me choose right voltage transformer

Discussion in 'General Electronics Discussion' started by Raigar, Oct 20, 2012.

1. ### Raigar

8
0
Sep 25, 2012
Okay so my Xbox 360 Slim Power supply has:
Code:
```     Input Voltage: AC 100-127V 47-63Hz
Output voltage: DC 135W 10.83 A,
Power Plug: US Plug,
Size: 17 x 7 x 5.2cm? =```
I want to convert 220 voltage power to work on this Power Supply, so basically I need step down converter. Can you find me one on www.amazon.com that would suit my needs ? cheers

3,635
5
Apr 7, 2012
3. ### Raigar

8
0
Sep 25, 2012
I see but they bot have bad reviews. One for not handling the whole wattage and one it stopped working after 3 days. By the way, the power supply - it's 11 amps....

4. ### CocaCola

3,635
5
Apr 7, 2012
So look at others, I gave you the info needed to pick one, it's up to you to choose and make your own purchase... Reviews are like opinions, everyone has one, take them with a grain of salt unless there is overwhelming similarities in multiple reviews that would add credibility...

5. ### Raigar

8
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Sep 25, 2012
Okay so all I need to take care is about wattage?

6. ### CocaCola

3,635
5
Apr 7, 2012
In short, yes...

7. ### Raigar

8
0
Sep 25, 2012
And amps? what are they for?

8. ### CocaCola

3,635
5
Apr 7, 2012
Watts = Amps x Volts

9. ### Raigar

8
0
Sep 25, 2012
Thanks for clearing me that but.. PSU is 11 amps, how did we get those 135 watts ?

10. ### CocaCola

3,635
5
Apr 7, 2012
Your copy and paste of the info was lacking, the voltage to be exact...

But, using simple math we can get the answer...

135 = 11 x A

So A is about 12.3 Volts, is that what is says on the tag for the output?

The reason for going higher on the total wattage is that there is a loss in the conversion and as you found in the reviews the device might not actually make the full output and even if it does, no need to push it to the limits...

So if you need 135W, you get the 200W unit and it's only working at about 68% of it's capacity lots of head room if the specs are off a little bit... Get a 500w unit and it's only working at 27% of it's capacity, even more head room...

Think of it like your car, your car might be able to max out at 100MPH but it will likely be happier and last longer if you only go 50MPH...