What fuse do I need for a trio of sockets - 2x 12V cigar lighter style and 1x USB? Not to be used for cigar lighters but for things like chargers and a 48W electric coolbox. Wire is 2.5mm2 so rated 20A. Holder is a glass fuse type so can only get certain ratings. Would a 15A do? This is what I used for my Mini lighter socket but that was only 1. Also these two interior lights: http://www.justkampers.com/slimfit-interior-light.html & http://www.justkampers.com/211-947-111-b-interior-courtesy-light-for-vw-t2-bay-1967-1975.html They take a 16W and 10W bulb respectively. Any ideas what fuse for both on the same circuit (coming from leisure battery not fuse box)?
I'm not sure if they do 8A in the size of glass fuse I need... Does it matter that there are 3 sockets in the set? I don't want it blowing all the time
12V, 26 watts is just over 2 amps. Chargers rarely pull much over 2 amps, so with three (inc USB) a 10 amp would be sufficient and well below the rating of the wire, however a coolbox for example can pull 8 amps on it's own. It really does depend on what you're plugging in to it. EDIT: Your coolbox will pull 4 amps.
So let's say 2 chargers and a coolbox = 8A max so 10A fuse would do? If I went 15A would there be a problem? And a 5A for the light circuit? It's currently (no pun intended) got a 8A fuse I think on the fuse box... Fuse #8.
Depends on what the chargers pull. If the cool-box pulls 8 amps 1o may not be enough. I know nothing about electrics though.
In short, no problem that I can see. The fuse is only there for when things go wrong to stop a dead short or significant overloading and the resulting fire. The wire is rated at 20 amps so the fuse will go long before any other issues arise.
If your coolbox cigar lighter connector centre pin is a bit dirty the plug will get very hot. The sockets although rated at 10A each will quite happily melt with 4A constant drain and a thermoelectric coolbox connected. I would suggest using some better connector for the coolbox, the cigar lighter plugs also tend to vibrate out. Because I am a yottie I use Buccaneer plugs that cost about £7 each but I happened to have them lying around from a boat restoration project a few years back where £7 is just in the noise.
This is what I have in the back: https://www.roadpro.co.uk/retail/12...ets/pro-car-triple-sm-socket-inc-usb-1015.htm It's rated at 16A so I think a 15A fuse will do it. It's also brand new so no dirtiness there. @mikedjames Are you telling me my electric coolbox, which has a lighter socket end, will melt a cigar lighter?? Surely these things wouldn't be sold. It's an Outwell Ecocool with only a cigar lighter plug, no mains.