I am adding a circuit to my internal fusebox for a second cigarette lighter. I've used a 10A fuse, which I think will be enough (correct me if I'm wrong - it's to provide power to a mobile phone charger). However, I only had three spare fuse sockets in my fusebox. As you can see from the diagram, which is on the inside of the fusebox cover, each socket appears to have an Amp rating, which surprised me because I don't see how a different current can be getting supplied to different parts of the fusebox.

My question is, will it matter that I've added my circuit, with its 10A fuse, into a socket which that digram has annotated with 7.5A?

 

You can check the fuse box main bus, but I suspect all connections are the same and you see amp ratings to 20A. The values assigned to non-used positions are likely values for add-ons your vehicle does not have. Use of 10A fuse should be fine.

good luck

 

agreed. in reality, a mobile phone charger won't draw more than an amp or two. the fuse should be sized for the wire used since the fuse is intended to protect the wiring.