Hello, 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) (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?