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car cigarette lighter power supply? Answered

I desperately want to install a electric car lighter into my coffee table, but am having trouble figuring out a proper power supply. I am a complete dummy when it comes to anything involving electricity, and would very much appreciate some ideas



Best Answer 4 years ago

Benmurton is correct you need a 12volt power supply.

The car lighters I know were fused at 20 amps
So you need a 12v 20a TR Unit like this one $16
add an AC power cord and 10 AWG gauge wires to your smoking table.tighter.

Remember car lighters are mounted in metal that can pass excess heat to
a vehicle structures, unlike wooden  tables that can be fired !!!

Thank you very much for the link, and for the warning about excess heat!

BTW that switching supply wont actually deliver 12VDC until it sees over a 15% of its load
Don't panic if you work with a voltmeter..


Just use a small car battery or two 6v flashlight batteries in series. Like so you also have the benefit of portability and no need to use wires to an outlet.


4 years ago

bobertson may not understand this is a 4way conversation.

Did we help you ?

Someone here deserves a Best Answer from you..............

A cigarette lighter socket is essentially a cylindrical hole. Supposing the axis of that cylinder is oriented vertically, normal to the surface of your coffee table, then the lighter socket is a hole that stuff can fall into.

For that reason, I humbly suggest a cover of some kind for it, or just leave the lighter gizmo in it when the socket is not in use.

I also suggest putting a fuse
in series with this socket, so that in the event that a penny, or a paperclip, or whatever, does fall into the socket, then the fuse will blow and protect your power supply.

The way that trick works is to choose a fuse rated at a current in between the amount drawn by normal use, and the maximum of the supply.  For example if the lighter gizmo takes 10 A (amperes), and the maximum of the supply is 20 A, then use a 15 A fuse.   

That way normal current draw, at 10 A, does nothing to the fuse, but if someone drops a penny into the socket, then the current will (briefly) be the maximum the supply can produce (around 20 A ) and burn out the fuse, since 20 >15.

They are 12v so a 12volt battery, Computer power supply or a wall transformer, if you can find one that will supply the required current that you are likely to draw.