I'm going to confine this to the most common outlet you find in the USA home. The ubiquitous three prong 15 Ampere socket is good for 15 Amperes but as you can imagine in Britain it's a little less due to a higher voltage (http://en.wikipedia.org/wiki/BS_1363 )
So grinding it finer we have to look at the TV specs. http://www.avsforum.com/t/1251257/does-a-60-inch-lcd-consumes-425-watts-all-the-time shows a set with 425 Watts but a Watt meter comes in at half that. But only the foolish would use the lower number when planning.
OK, the 15 amperes at 100 volts (I'm purposely making the match simple for a few reasons) gives us 1,500 Watts so that's all we get for one outlet.
Hope this helps.
Bob
I'm sorry if this topic is in the wrong location, but this was the only place I thought was suited for the question. I'm hoping someone can answer this because I have tried figuring this out on my own, but it's giving me a huge headache and haven't been too successful. Last thing I need is for my home to be catching on fire...
I'm trying to set up an entertainment room, but I'm worried I'll overload the wall outlet with everything I need to have plugged up. I have three 60" LED TVs, an U-verse satellite receiver, Playstation 3, Xbox 360, 5.1 surround sound, and a PC I need to hook up (using the three TVs for monitors). And when released, I'll be getting a Playstation 4. At a single time, I'll have the three TVs running, the home theater system, and three of the electronics running at the most.
If need be (which I'm pretty sure is definitely needed), getting another outlet installed isn't that big of a problem; I just need to know if it's completely necessary, approximately how many watts will be used (or how many volts needed...whatever the correct terminology here would be), and about how many outlets would be needed for such a heinous task?

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