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caineroad
05-15-2013, 01:18 AM
I am connecting some LEDs for decoration in the car, the LEDs are rated are 1W each, I will be connecting that to the cigarette lighter wire. I am wondering would a 26AWG gauge wire be enough connection between 12V and the LEDs?

Thanks

CTScott
05-15-2013, 06:11 AM
26 AWG stranded wire is rated for about 2.2A, so you could theoretically power 25 1W LEDs off of it (as each draws .08A).

caineroad
05-15-2013, 09:31 AM
Yes, I am wondering though if I do with 26AWG which is ok, but what happens if I plug in a power inverter or something that draws a lot of energy in the cigarette lighter which will brings a lot of current, is it going to have problems or burn out my 26AWG that is attached to the cigarette lighter wire?

thanks

CTScott
05-15-2013, 09:52 AM
Yes, I am wondering though if I do with 26AWG which is ok, but what happens if I plug in a power inverter or something that draws a lot of energy in the cigarette lighter which will brings a lot of current, is it going to have problems or burn out my 26AWG that is attached to the cigarette lighter wire?

thanks

It won't have any effect. The devices connected to a piece of wire will only draw more current if the voltage sags when another device is plugged in to the system.

So, for your LEDs, my 25 above was based on a system voltage of 12V, as opposed to 14V when the alternator is spinning. When the engine is running you will draw less current than when it is off (higher voltage = lower current).

I would recommend though installing a 2A or 4A max fuse inline with your LED wiring. The fuse for the lighter is 15A, so if you accidentally shorted your LED wiring the 26AWG wire would burn up, without popping the 15A fuse, so to be safe when you branch off a circuit with smaller wire you should always add a fuse appropriately sized for the branch wire.

caineroad
05-15-2013, 10:35 AM
Wow, very informative and knowledgeable, thank you very much again! Will follow your advice to adding a fuse.

BLH
05-15-2013, 11:11 AM
Just don't connect the inverter to the 26 gage wire. In that case it is too thin for the needed current.

cali yaris
05-15-2013, 01:28 PM
If you hook up lighting to the cigarette lighter circuit, won't it only work with ignition on?

CTScott
05-15-2013, 01:34 PM
If you hook up lighting to the cigarette lighter circuit, won't it only work with ignition on?

Correct

caineroad
05-15-2013, 07:38 PM
If you hook up lighting to the cigarette lighter circuit, won't it only work with ignition on?

Yes, that's right. I am installing interior mood lighting, similarly found in Mini cooper, not the lighting to use in event or shows.