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L.E.D desk lamp run on 12 volt? Answered

So I have an L.E.D desk lamp that plugs into the wall. It is hardwired into a power adapter witch  converts 120 volt to an output of 14 volts, If I cut off the adapter can they be run straight off a 12 volt battery. It is very bright so some lost light is okay, I fried the inverter for my cabin and need some light. 


I would say it should work as long as you get the polarity right, 12 volts DC out of 14 volts DC should not make much of a difference.

Where you might run into a problem is if the adapter's output is 14 volts AC.

Actually just checked and the adapter says the output is 14volts DC!! Should work fine thanks for the help!!


2 years ago

I had such a lamp and the 14 volts was AC.. That LED lamp had internal electronics and would not run on a DC supply.

But my clairvoyant view is unable to actually visualize your situation even though you are connected to the net, maybe the light of your screen is enough.

I figure that's what mine is like but Im hopeful it will work on twelve volt. Thanks for the help!!

Just checked and the adapter says output 14volts dc guess I should have looked closer

You should try this. The cost of failure is one LED desk lamp, so I think it's worth the risk, although I am unsure of the cost. Maybe it's a long way to the store, or a long wait for shipping, to get a new one?

I know you'd prefer an answer with certainty; i.e. your plan definitely will work, or it definitely won't work, but I don't think you've told me enough details about the problem to know for sure.

The truly clairvoyant answerers here may be able to actually visualize all the missing details somehow, like the character of the adapter ( is it a typical constant voltage adapter, or is it a special constant current adapter made for driving LEDs?), how current limiting for the LEDs is achieved (is it a regulator circuit, or just some resistors?), also how do you know the output from the adapter it came with is "14 volts"? (probably by reading some numbers printed on it, amirite?)

A non-destructive trial may be possible, if you're fast enough. I mean connect the battery for a fraction of a second or so, and if the lamp seems brighter than before, then quickly disconnect it.

I also don't know how fast would be fast enough for that trick to actually work, but I think you just came to this forum because you, for some reason, lack courage to try something you already think is going to work. Or maybe you want certainty? Or someone else to blame if you fry your LED desk lamp?

To me this question, of will-it-work-won't-it-work, feels like a stochastic problem, so luck applies. Therefore, I wish you good luck!


I think Ill give it a go Im not in a huge hurry I would just like some light when I go up there. Thanks for the help!! :)

I would just get some 12V LED lights.
The stuff is so cheap these days that messing with existing lamps is mostly a waste of time and money.