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Other Changing US plug to UK plug

Discussion in 'Tech Support' started by smc8788, 22 Sep 2010.

  1. smc8788

    smc8788 Multimodder

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    I lost the battery charger for my camera on holiday, so I picked up a new one while I was there, but as it has a US plug that means I would have to buy an adapter to use it over here. I know they're only cheap, but I have a few spare plugs lying around and for convenience sake I was wondering if I could just cut the US plug off and rewire it to a UK one? I'm guessing that's not a problem since the charger says it accepts a 100-240V 50-60Hz input, but the cable only has 2 wires, which I'm guessing are live and neutral. How do I know which one is which? Or does it not matter? Does it matter that it doesn't have an earth wire? And how do I know what amp fuse to use?
     
  2. Gryphon

    Gryphon What's a Dremel?

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    It will work.

    Live wire is normally brown, neutral is normally blue. A charger will be insulated (class 2 product), so it doesn't really matter which way round you connect live and neutral anyway. It also means it doesn't need an earth, so don't worry about that.

    For fuses... smallest you've got? Chargers have a very low power draw. 1A or 2A would do fine.
     
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  3. capnPedro

    capnPedro Hacker. Maker. Engineer.

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    3A fuse will probably be the lowest rated that you can find which will still fit in the plug's holding tabs.

    I did this to the Hong Kong plug on my flashlight battery charger, and I did it to my EU guitar amp's plug as well. Oh and my ex-girlfriend's EU hair straighteners.
     
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  4. smc8788

    smc8788 Multimodder

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    Yeah, I could only find a 3A fuse in my box of spares, so I guess that will have to do. After hacking off the plug it turns out the wires aren't actually coloured though (just bare copper), which I suppose is OK if it doesn't matter which one is used for which.

    Thanks for the help :thumb:
     
  5. Pookeyhead

    Pookeyhead It's big, and it's clever.

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    Theoretically, as it's AC.. it shouldn't matter which way around live and neutral is.
     
  6. Gryphon

    Gryphon What's a Dremel?

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    I'd agree, and in this case it's true, but if it's an uninsulated product with an earth connection, then apparently it does make a difference, and causes a ground loop. I'm not sure why though - from what i know about AC it doesn't make sense.


    And yeh, sorry - 3A fuse. I couldn't remember how low they went.
     
  7. capnPedro

    capnPedro Hacker. Maker. Engineer.

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    Because you're actually using a single phase of a three phase supply.

    When you have a power transformer which is not earthed, both wires are live and both have some potential. However, because it isn't earthed, current cannot close a circuit through earth and you cannot measure any potential between either wire and earth (hence 'isolation transformer').

    The only potential is between the two wires from the transformer - when you earth one end of the coil, you then have only one wire at 230V (it goes from -230V to 0V to +230V in one time period) and that become neutral since the potential is always at 0V. Your other wire becomes live/'hot'.
     
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  8. Gryphon

    Gryphon What's a Dremel?

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    Thanks!

    Took me a while to get my head around that... I use ground as a reference voltage for DC without thinking about it, but I'd never thought about doing the same for AC. For some reason I'd just assumed any current would flow to ground, and not thought about it any further...

    Makes sense now :)

    I shall add to your not inconsiderable rep :)
     

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