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ArcticMyst Security by Avery

MultiColor LEDs

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Ok I have about 5 leds i want to run.
They are the ones which slowly change color and I was wandering what resistor I'd need to do it off of 12v.
I figure it would need to run in parallel.
Its for a fishtank :)
 





cd520

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If memory serves me 5 of those could be run in series off 12V and be close to max brightness. Need to know the forward voltage of them to really answer the question.
 

cd520

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For each LED being powered by 12V. You could also find a single higher wattage 470 ohm resistor fed by 12V to feed all of the LED's too.
 
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For each LED being powered by 12V. You could also find a single higher wattage 470 ohm resistor fed by 12V to feed all of the LED's too.

This system is not recommended if you mix colors, because each color has a different voltage, especially among the red and blue, "and sometimes also the current consumption is different"

Typically for this type of LED (5mm and 25mA Approx.), the voltage for the red is usually 1.8V to 2.2V approx, and the blue is usually 3.6V to 3.8V typically, "depending on the wavelength of each color and manufacturer".

Therefore, it is not advisable powered different colors with the same resistance, because then it can happen that a color is outside the range of voltage and consumption, above or below.
 

cd520

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This system is not recommended if you mix colors, because each color has a different voltage, especially among the red and blue, "and sometimes also the current consumption is different"

Typically for this type of LED (5mm and 25mA Approx.), the voltage for the red is usually 1.8V to 2.2V approx, and the blue is usually 3.6V to 3.8V typically, "depending on the wavelength of each color and manufacturer".

Therefore, it is not advisable powered different colors with the same resistance, because then it can happen that a color is outside the range of voltage and consumption, above or below.

Perhaps you need to read the OP, the 5 LED's are the same. These are fading multicolor LED's.
 
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To me it looks like each color flashes in sequence every 3 to 5 seconds. Just a heads up before you buy a bunch, maybe buy a small batch to test with first.
 
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There are a few problems I see with this:

You'll have to be careful about isolating these from the water as mineral deposits can short things out.

They are not bright enough to light the fish tank

Even if you have another light source, these will barely be noticeable next to it.

Even if you ignored the first three factors, they won't be synchronized. The fish tank will just look white most of the time - especially with 20 of them.
 
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I agree with cyparagon, but if you want to power them connect a 470 ohm
or there abouts to EACH one then to you supply so you end up with
20 parrellel ckt's connected to your supply.
 
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