Fuse for a phone charger

[ab]

I had someone put in the wiring for a phone charger.  But I notice that there is no fuse.
Can you guys point me to some directions on what I need to do to add fuse? How do I know which fuse to get?  Which wire do I splice to add the fuse?
I have 0 mechanical or electrical abilities.  But I know it's shitty job of the dude not to add a fuse.
Any info or pics to help me work on that is appreciated.

[battlecry]

Get the smallest (rated) fuse you can find.  Splice the fuseholder on the cable leading to the (+) terminal, generally the red cable.  Splice the fuseholder closest to the source of the current (battery or switch).  If you can, do it where it was spliced to the harness, this way the fuse will protect most of the wiring.  Get a marine or motorcycle type fuseholder, better for water and corrosion resistance.  Be aware and do not short the red (+) cable to ground if you cut the wire. 

Better to siphon the gas out of the tank, lift it, and disconnect the (+) terminal at the battery before you disconnect anything.   

[zooom]

http://www.webbikeworld.com/sale/posi-locks-for-sale.htm

get the Posi-Lock fuse holder and tap it in simple as pie and be done!

[DarkStaR]

Depending on where they tapped the power from, it might be on a circuit that's off of a factory fuse.  That said, running a fuse just for that accessory would be an extra fail safe.

Also, did they tap it to a switched power source?  If not you may have a slight power draw with the bike off depending on what exactly was installed.

[ab]

Thank you fellow DMF'er for the great answer.  I will try to do this.

DarkStaR - tapped the source from the battery straight and so there is always a slight draw.  I was told not to worry about it and that the draw is less than the clock.  is that so?  Honestly, it is in the back of my mind.

Zoom - I may end up getting the posi lock you suggested since I don't have solder (or ever tried it). 

Battlecry - Thank you for the detail answer.  That is exactly what i needed. 

[Howie]

Taking it off the battery is fine, but it would be better to use a fused circuit, this way the whole run of wire is protected.  If you do have a problem due to a short it is much more likely to be the wire, not the phone.