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50 of 51 people found the following review helpful
Great little light...should be used with a regulated power supply.
on November 21, 2013
I bought this to replace the IR lighting from my Foscam F18910W now that it sits inside a dome and the IR lighting reflection from the dome washes out the view.
First, it works great. Provides excellent illumination out to about 50' and its field of illumination is pretty close to the above camera. Of course its not going to track the camera movement so if I needed more areas illuminated I would need to add additional units.
One concern of mine was the number of reports of units burning out LEDs fairly rapidly. I did a little testing and found it draws abut 250ma at 12.0V, which is just about the sweet spot regarding input voltage versus illumination. The unit does not contain any voltage or current limiting device on the power input to protect it. Higher input voltages only increase light output slightly beyond that found from 12.0V while current continues to climb as a function of I=E/R where R is the effective forward resistance of the LED array. This means that voltages above 12V will cause the array of LEDs and resistors to have to dissipate more heat, which will shorten their lives...perhaps dramatically depending on the overvoltage.
The reason I tested for and mention this is because typical 12V "wall wart" supplies are not regulated and this is a problem common with other LED lighting arrays, such as those strips intended for accent lighting intended for . An unregulated 12V supply may produce upwards of 16V when completely unloaded and only reach about 12.0V when loaded to their current rating. A sample of one of these supplies that I have on hand that is rated (according to the label) at 12V 500ma operates at 14V when loaded with 250ma. Higher rated units, say 12V 1A could be expected to to operate at similar or even higher voltage into 250ma. Another problem with unregulated supplies is that the DC output voltage varies proportionately with incoming AC voltage. So even a supply that is operating at 12V loaded may produce much higher voltages out with AC power surges. To prevent this from becoming a reliability problem for this iluminator - and I suspect many other low cost similar versions - I recommend only using a 12V power supply that is specifically labeled "Regulated". This means the output voltage from that unit will remain at 12V from 0ma to the supplies rated output current and be much more resistant to output voltage changes due to varying input AC voltage swings.