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I have been doing some research on LED's. I found that there are some that put out around 4,000 mcd (milicandles). that's 000 millionths of one candlepower. Since these are DC, it'll be a lot safter. I won't have to worry about big ugly fixtures, the bulbs breaking, burning out, snakes getting burnt, etc. You can get a pack of 50 of these things for $5 online. I'm going to wire a bunch together and put on a small switch so I can see my snakes at night.

Any ideas to make this better or comments on it?

By the way, I have (4) 4x2x2 cages I built out of 3/4" oak ply, with a 1/4" back. I'm either going to mount all the lights in a row up top, or i'll put them all on the back with the wiring along the outside of the cage. If I put them on the top they'll be all inside, but i'll mount them in a bed of hot glue to seal away any hazards.
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The educated are the few. The uneducated are the masses.

Use red LED's for night-time, and high intensity white if you want brighter lights before bed-time. You can use any 12v ac/dc convertor (like from old cell phones etc.), they should have their output voltage on the adapter. You'll need to wire a series of resistors in line to drop the adapter voltage down to what the LED's are rated for (around 3V if memory serves). If you use just 1 resistor in line to drop overall voltage down to 3V (or whatever) and use more than 1 or 2 LED's, none will get enough juice to fire. It's a good idea, been doing the same myself for a long time.

The LED's i'm going to get are 1.8-2.0 V. If they are wired in series, (which i believe is a chain of positive to negative, right? Or am I backwards? I always screw the two up..) do I need to add the voltage of all the LED's together, like if i have 4 LED's i'll have just under 8 volts, or do I still run it at 2 volts?

If I wire them in parallel, i'll run it at 1.8-2volts, right?

Appreciate it!
-Chris
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The educated are the few. The uneducated are the masses.

You would be wise to use a parallel connection scheme, like the other poster said.

Lets say you are using a 12DC adapter. Each LED needs about 10mA of current (or whatever the LED is rated at. Some can burn bright at only a few mA.) So, 12V - 1.8V = 10.2V. To get 10.2V at 10mA, you need a 1.02K Ohms. So just use a 1K or 1.2K resistor in series with each LED, and connect all the resistors to the POSITIVE voltage output of the adapter, and the negative terminal of all the LEDs to the NEGATIVE output of the adapter.

Diagram: wwww represents a resistor; | is a parallel connection.

12VDC
|
|----wwww-----LED----|
|----wwww-----LED----|
|----wwww-----LED----|
|----wwww-----LED----|
|----wwww-----LED----| GND
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Mark G

wow, thanks. the bulbs i ordered are say Forward Current: 5 - 30mah - i'm presuming thats miliamp hours. so presuming i'd be getting a brighter bulb at 30 mah. you said i would need to drop it 10.2 volts, but at 10 mah it would be a 1.02k ohm resistor. how would i figure this for a 30 mah?
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The educated are the few. The uneducated are the masses.

If I wire say, 6 LED's in series, that would total a pull of right around 12 volts, correct? Then I could just wire these strands of 6 in parallel and completely ignore any and all resistors, correct?
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The educated are the few. The uneducated are the masses.

You can't wire 6 in series with no resistor.. you may fry them. You NEED to use a resistor. See the alternative diagram at the end of this post if you want to use fewer resistors.

BTW, in electronics, resistors are your friend. They prevent overcurrent and perform other necessary functions. If you work with LEDs you need resistors.

If you want 20mA through each LED, go with a 500 to 560 Ohm resistor on EACH LED. If they are rated up to 30mA, better to stay below 30mA, because those 12V transformers do not put out exactly 12V, sometimes up to 13.5V, so if you expect 20 mA you might get more in practice.

Another alternative with fewer resistors:

12VDC
|
|
|-----wwww---LED---LED---LED----|
|-----wwww---LED---LED---LED----|
|-----wwww---LED---LED---LED----|
|-----wwww---LED---LED---LED----|GND

Use a 300 Ohm resistor or close to that for the above.
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Mark G

I did some more research and discovered basically what exactly you just told me. Thanks!
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0.1 Licorice Stick Black Rat
1.0 Black Rat
0.1 Vietnamese Blue Beauty
1.0 Green Tree Python
0.1 Texas Bairds Rat

The educated are the few. The uneducated are the masses.

North American Rat / Corn Snake Care Sheet

We use LEDs in a lot different applications at work. I had even posted a while back that they might be neat in those Freedom Breeders with the clear fronts.

I think it could be a good possibility because with some of the flashlights the beam is more non focused moonlight than a penetrating light.

I think you are on to something. I lack the electrical skills to even try some things. I wish you luck. Maybe you can keep us posted.
Bob.