Gauge of Wire for 12 v wireing

[Bigplumbs]

In my little Sealine S24 I want to wire 2 12 v sockets in the main cabin as I don't have any. They will generally only be used on low consumption thigs such as a 12 v TV or charging phones etc. I was wondering what gauge of wire would be the best to use. I was thinking 12 - 14 AWG twin core wire

Anyone able to advise.

Also the best cigarette lighter style sockets also that people may have used

Regards

Dennis

 

[vas]

not particularly good with AWG we use something else as a measurement down here and I'm always confused...

BUT, Dennis, since most of the things you're going to be plugging in are going to be USB devices, find decent 1.5A or better 2.1A USB sockets and fit them straight away. I've solved all my charging problems with decent ones (only I built them myself for my VIMAR h/w which is not suitable to you. I do remember others pointed to decent quality devices that weren't silly priced.

cheers

V.

 

[Colin K]

not particularly good with AWG we use something else as a measurement down here and I'm always confused...

BUT, Dennis, since most of the things you're going to be plugging in are going to be USB devices, find decent 1.5A or better 2.1A USB sockets and fit them straight away. I've solved all my charging problems with decent ones (only I built them myself for my VIMAR h/w which is not suitable to you. I do remember others pointed to decent quality devices that weren't silly priced.



cheers,

V.

Hello,
I did just that but regretted it and so now have one of each. A cheap smart dedicated usb and a trad cigarette type one. I still have the odd thing that is not usb eg the oil drain pump, I have a roaming bilge pump and a cpl of others.

I think I use 12AWG which from memory is ok for 20a depending on the length of run of course.


Cheers, Colin.

 

[waynes world]

I have fitted a couple of these type, could be the same as there are so many about nowadays

https://www.ebay.co.uk/itm/Dual-USB...610521&hash=item44196cd850:g:qK0AAOSwLe5aqlwo

Te wire gauge will depend on distance from load etc etc. Not that much up on the tech stuff, i sue these guys for help and supplies a lot.

They have a very useful Knowledge centre with calculators to help work the wire size.

https://www.12voltplanet.co.uk/

I used 3mm with a 6m one way cable run.

Wayne

 

[Richard10002]

I've always tended to find that voltage drop is the limiting factor rather than the amount of current a cable can handle.

12-14AWG appears to be about 2mm2 to 3mm2. With a 5A draw, (60W TV ??), 6m one way distance to the battery bank, and 3mm2 cable, the voltage drop will be 0.34v, or 2.83%, which is OK.

However, it might be worth future proofing by using 6mm2 cable which would allow you to draw 10A for the same voltage drop.

 

[Assassin]

Most wiring for automotive and marine applications now comes in metric sizes and these have a number:

17/0.30 as an example.

17 is the number of strands it contains
0.30 is the diameter of each individual strand

A combination of both of these gives the CSA or cross sectional area of the cable in millimetres squared, and this determines the load carrying current of the cable, and unlike fixed home wiring it contains multiple strands to make the cable flexible so it absorbs the vibration of a moving vehicle such as a car or boat.

Tings aren't quite that simple though as you can get a standard cable and a thinwall cable and the difference is the insulation on a standard cable is PVC to a defined thickness, on a thinwall cable they use a modified PVC which is much stronger and thinner to save weight, and you can get plain copper cored or tinned copper cores and for marine use a tinned copper core is much better at resisting a salt laden environment.

Distance is a factor and you need to allow for this by installing an oversize cable, and as for a cigarette lighter socket I would say forget it as vibrations and knocks dislodge then and anything you plug into them stops working, sometimes without you knowing about it, a much better option is a bulkhead plug which screws to your panel and they have a twin (or more) terminals of the standard 6.35mm and one is turned at 90 degrees to the other so you cannot plug something in the wrong way round, and they have positive locking so anything plugged into it wont accidentally fall out or be disconnected.

Cigarette lighters are generally rated at 10 amps and by cable specifications show that a thinwall 32/0.20 cable has a rating of 16.5 amps and a standard cable of 28/0.30 has a rating of 17.5 amps and either will suffice for a standard 10 amp rated cigarette lighter socket with a 10 amp rating, and with enough spare capacity to overcome any voltage/current drop.