what size inline fuse?

[jim1987]

I recently added an extra 12v source in my Dakota. So I can have the cigarette lighter and a phone charge. But right now its just direct connect to the battery. I know its better to have an inline fuse, but don't know what size. I'm thinking 15a or 20a. I'll be using the regular little square fuses. 90% of the time only one phone will be plug in, with the other 10% 2 phones will be plugged in.

So, simple question, what size inline fuse would you use?

 

[theoldwizard1]

If you are going to use a real cigarette light, it had better be 20A. If you are wiring directly to the battery, the fuse should be as close to the battery as possibly.

 

[jim1987]

No no. The factory outlet is for the lighter. The one I added is just for phones. But either way, theres not a cost difference in fuse price. Lol

 

[teamextreme]

Fuse should be sized to protect the wire and therefore mounted as close to the battery as possible to minimize the length of wire that is unprotected. What size wire did you run? That will tell you what size fuse to use.

 

[jim1987]

Hmmm... 14 or 16? But I had to add some 12 or 10 a few inches at the end because it wasn't long enough. Id say total wire length is 3.5-4'.

 

[CJM8515]

I always try to find the smallest fuse that will work before it blows. This way should it barely overload it will blow the fuse. Considering most cig/power outlets are about 15-20amps Im sure you should be somewhere in 10-20amp range since its only for as phone

 

[Syberia]

You should be fine with 10A. Most phones will use less than one amp even at 12V.

 

[jim1987]

I always try to find the smallest fuse that will work before it blows. This way should it barely overload it will blow the fuse. Considering most cig/power outlets are about 15-20amps Im sure you should be somewhere in 10-20amp range.

Well that don't really help at all... lol

 

[G_P]

If its for phone charging only, 10A max. But in any electronic circuit the wire size is going to determine that max fuse size you can run.

 

[jim1987]

Thanks

 

[CJM8515]

Well that don't really help at all... lol

Put a fuse in it blows go up next size till it don't. How hard is that?

 

[jim1987]

Put a fuse in it blows go up next size till it don't. How hard is that?

Or ask people here who actually know what id need and not waste time/money. I can guess all by myself without help.

 

[Hpozzuoli]

15 amp will cover your charging and small things.

 

[jim1987]

15 amp will cover your charging and small things.

Thank you. I believe that's what I'll go with.

 

[BillK]

Jim,
Depending on which chart you look at, 16g wire is rated at "around" 15 amps and 14g is around 20 amps depending on if it is open air or enclosed etc. I would use a 15 amp fuse and that should safely protect it.

 

[jim1987]

Thanks bill

 

[wyliesdiesels]

15 amp will cover your charging and small things.

As has been said many times, the fuse size is determined SOLELY by the gauge of the wire NOT the electrical needs.

 

[Tarheelgarage]

As has been said many times, the fuse size is determined SOLELY by the gauge of the wire NOT the electrical needs.