Powering 12v device

Discussion in 'General Chat' started by danmc_82, Jun 28, 2015.

  1. danmc_82

    danmc_82
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  2. MrSossidge

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  3. danmc_82

    danmc_82
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    Looks a little overkill :D

    I was hoping more along the lines of a transformer which I could connect bare wire.
     
  4. RBZ5416

    RBZ5416
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    A 12V AC adapter of around 1A would do the job as the combined load is only 500mA. You may well have something kicking around as 12V is quite common. Just need to cut the jack off & identify +/-.

    Do you need the LED display? You can pick up self contained battery powered LCD jobbies cheaply. A quick example but cheaper options probably exist.

    Voltcraft LCD Digital Thermometer and Clock -10 to +110 °C | Rapid Online
     
  5. MrSossidge

    MrSossidge
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    I have the dual one to charge my lipo batteries for the r/c cars.
     
  6. danmc_82

    danmc_82
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    Yes needs to be on all the time. Was just checking I can use a standard adapter. Thanks
     
  7. danmc_82

    danmc_82
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  8. wilbanat

    wilbanat
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    These are handy Link for the connection end
     
  9. danmc_82

    danmc_82
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    Cheers, very useful. Didn't know they existed.
     
  10. wilbanat

    wilbanat
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    Yeah they save cutting off molded plugs and voiding warranties ;)
     
  11. danmc_82

    danmc_82
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    Ahhh gotcha. The adapter I linked too ok for the task?
     
  12. RBZ5416

    RBZ5416
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  13. nheather

    nheather
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    Any old 12v charger you have lying around will probably work but a tiny bit of caution.

    Some run are not very well regulated and can run at upto 20v.

    The thing that they are meant to charge have switch-mode circuitry which switches the voltage input on and off at a high frequency and varies the mark:space ratio to get the voltage/current that it needs. They do this to make the components small and to be able to charge quickly.

    To be safe you sould be looking for a 12v DC power adator rather than a charger.

    Cheers,

    Nigel
     
  14. danmc_82

    danmc_82
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    Thanks but needed a light up display.

    How did you get the calculation of 500ma. When I did the calculation I got 1.5a :confused:

    By the way I don't have any knowledge on the subject, I just Google things. :D

    Edit: Just did another calculation and got what you got. :thumbsup:
     
  15. danmc_82

    danmc_82
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    Isn't the one I linked to an adapter? I don't have any 12v lying around, just 6v and 18v.

    I need two anyway so will just buy them.
     
  16. nheather

    nheather
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    Yes, sorry I missed your link.

    As for current required - the link in your OP says power consumption < 3W.

    Power = Current x Voltage

    So Current = Power / Voltage = 3 / 12 = 250mA

    So two will require 500mA

    Cheers,

    Nigel
     
  17. wilbanat

    wilbanat
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    Yep, I was going to suggest a 'CCTV'one as they are designed to be constantly on and the output should remain fairly stable, I've used similar to power 12v devices. I once put a car stereo in my kitchen, had a stud wall that I could sink it in and ran cables to ceiling speakers.
     

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