Discussion in 'The Projects Forum' started by Lightfire, Mar 2, 2011.

  1. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010

    I had two fuse but I don't know how to use these.

    My fuse specifications is

    30 AMP 250 VAC

    It's something like this one: http://www.bitsbox.co.uk/images/hardware/13A_fuse.jpg

    But I don't really know where to put these two two fuses in my simple DC circuit.

    Firstly, my simple DC circuit will be operated by a 12 dc volt battery and consists of only 1 halogen lamp (50 w 12 v) with a switch on negative terminal.

    (Is is okay if I will put the switch on the negative terminal of the battery?)

    Here's my semi-schematic (I'm just kidding with semi. Don't be confused) :D (Please look at the attachments below)

    As you may see, there are one device (which is the halogen lamp), one switch (which is in the negative terminal), two fuses (250 VAC/30AMP) which are in the both negative and positive terminals and last the 12 volt battery (wet cell).

    Thank you again and I am very sorry for the hateful thread I have posted last days.

    Now, is my connection correct? For example, it gets short-circuited, the two fuses will going to fix it?
    Last edited: Mar 2, 2011
  2. nerdegutta


    Dec 15, 2009
  3. Lightfire

    Thread Starter Well-Known Member

    Oct 5, 2010
    Well, yes, it is. But yes also, it's 13 amperes. I was pointing that the design were just the same like the one I has.

    Anyway, my fuse should be rated exactly? I mean everything should be exactly.

    For example my circuit was rated 12 volt dc, then my fuse should be 12 volt dc too?

  4. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    You could use an ATC type fuse or any other DC rated fuse with a voltage rating higher than your circuit voltage.. Fuses are typically rated for DC or AC.. For example the ATC fuses are typically rated for up to 28 or 32VDC.. That is fine.. Now you need to find the correct amperage for your fuse.. Typically 120% or so of your current requirement. For example.. if your device draws 10 Amps of current (fully loaded) you would pick a 12 Amp fuse.
    Then you can even look at a fuses time curve to determine how fast it will blow in an over current situation. and on and on