Ikea work light Again

[Pirate]

I bought 3 of the lights ($40 including shipping)
My wife said she could use 2 in the house, and I wanted to try one in the shop.
A simple mount mounted it to my old Delta bs.
The amount of light for the bs is ok, but in the house it could be brighter.
The power supply has an output of 7 volts. I'm wondering if it would work with 12 volts. I have a few 12 volt power supplies.
I have a led flashlight which uses a AA battery (1.5 volts) or a 14500 battery (3.7 volts) The 3.7 is quite a bit brighter.

Anyone know if it will work with 12 volts, or if it will trash the led?

[jppierson]

Depends on how much circuit work you want to do to keep the LEDs from becoming fuses. Here is a forum thread that discusses resistance and current control. Scroll down to the last 3 posts and I think your question may be answered.

[EricU]

the more current you run through an LED, the shorter the life. They will grow dimmer over their lifetime, even at below their max rated current. I am too lazy to read LED emitter data sheets, but I assume these characteristics are noted there, or maybe you have to sign a non-disclosure to get that info. Note that in a commercial products, the LED may be run below their max current due to lack of heatsinking, because heat will kill them too. It's also possible that they are just slapped together and not a lot of care is put into these decisions. Or the device may be made to accommodate many different devices and the settings are for the worst one they expect to use.

My experience shows that they do ok above the max current rating, but not that long. One issue will be identifying the emitter so that you can make these sorts of decisions yourself.

Are their multiple emitters in these lamps? For a single emitter, 7 volts means they have an active circuit, and just changing the input voltage will probably just fry that. OTOH, if it's multiple led's in series, then they may not have much of a circuit and you will probably blow the emitters going to 12v. The way that LED's work is that they drop a certain amount of voltage. It turns out that a single Li-ion battery probably will not over-current a power led, but it's really close. An AA will drive it, but at much reduced current and light output.

[Pirate]

Thanks. Guess I will leave it alone!