Simple question.... I think.

A certain item on my build requires a 15 amp fuse.  How much higher rating wire do I need?  Just more than 15, or is there a sort of scale, e.g. fuse rate plus a minimum of 10% ??

Thanks

If it uses a 15amp fuse it will consume less than 15amps or the fuse would blow every time it was turned on 15amps at 12v is 180watts load. Go for a wire about 18amp as length has an effect but buggies have short looms.

spelling is crap on the i pad so just tweeked it.

Cheers Snoopy

As a general rule of thumb when we are wiring up stuff here, we make sure the preferred value of available cable is as close to double the fuse rating as we can get.

15A fuse - (doubled is 30A) - closest rating of easily commercially available (and therefore cheap) cable to this is 27A, and thats close enough for us.

If not, the wire can start to get a little "warm" if you approach the fuseable rating as a constant draw.

As a rough rule of thumb, you can use the current carrying capacities as used by electricians to determine the correct cable size for a given current requirement (this is then qualified by a few other factors such as voltage drop, grouping, insulation, etc to give a more accurate figure and potentially go up a size, but these figures will do as a guide).

1mm2 - 11A
1.5mm2 - 14.5A
2.5mm2 - 20A
4mm2 - 26A
6mm2 - 34A
10mm2 - 46A
16mm2 - 61A
25mm2 - 80A
35mm2 - 99A

This is for PVC coated cables, silicon coated cables can handle higher currents - as used in Radio controlled models.