12V / 2.4W solar charger installation: which fuse size?

[alex23]

Hello there,
I've just installed a 'Ring' Solar Power Battery Maintainer, 2.4Watt, 17.5v(max) with a current of 138mA to use on a 12V / 610A battery on my VW van.
I've connected the solar charger to a 'sunsei' CC10000 charge controller, to which the battery is also connected with two flying wires that I only connect when I leave it unused for a few weeks.
I am not sure which fuse size to install on the positive cable from the battery going to the charge controller, the smaller I had today was a 5A but it's probably too big for the job?? The cigarette plug which came with the solar charger has a 0.5A fuse, do I need to use the same size?
I live in UK, so not the sunniest place (!) but I want to be safe and avoid my van catching on fire!!!
Many thanks.

[Mike90250]

Generally, they don't make a fuse of the right size for your charger.

To be safest, you need 2 fuses, one a small 1A fuse going to your charger
the other , a proper size fuse for your loads & + wire.
Both fuses should attach to the + terminal, and the wires on the - terminal should be the same size as the matching + wire, or the wire melts before the fuse does.

Locate a wire table to determine the right fuse for the size wire you use.