Quote: Originally Posted by
ado0o 
the regulator is having a bulit in fuse
that fuse only protects the regulator itself
Quote: Originally Posted by
ado0o 
should i put an external fuse?
yes, an in-line fuse is required within a few inches of the power source. this is to protect the power wire from staring a fire due to a short circuit or drawing too much current. the fuse cannot exceed the ampacity for whatever wire gauge you use.
this site has some good info on wire guage, ampacity, and fuse ratings.
Quote: Originally Posted by
ado0o 
if so .... tell me where to put them ??
you must put a fuse at the beginning of any power wire, and anytime you reduce wire gauge or split into two or more smaller wires (unless the smaller gauge wire can handle the current that the main power fuse is rated for).
remember, its always ok to downsize a fuse, but NEVER go higher than the wire can handle.