wiring LED hole lights

[fishing addict]

I have seen discussions about using LED lights for hole lights. I have been looking around and only radio shack carries these. the problem is that the brighter ones that I think I will need are rated for only 2.4volts . How can I wired these to work in a 12V system. Has anyone else done this in their fishouses ? Any advice is appreciated. I was told that resistors may be used to do this but I have no clue how to do this and the guys at radio shack had no clue either.

[LOWinEYEin]

I might be able to come up with something this weekend. Will post Mon.
For Permanent or portable?

[This message has been edited by WhaTT! (edited 11-07-2003).]

[fishing addict]

Permanent. I've wired regular 12v bulbs on the ceiling but I am looking for a way to not use up so much juice , when we need light around the hole only. I have considered using a head lamp but would be nice to mount something on the wall.

[LOWinEYEin]

Do you remember the wattage of the LEDs?
The lower the wattage the less juice it uses.(for the regular bulbs)

[Guest]

First off, it doesn't sound like something you'd want to do. Buy some AA batteries and run it instead.

That said, you'd have to make voltage divider to drop the 12 volt source to just the 2.5 volts across the LED. Make a resistance source across the LED with a resistance value of say x*(2.5/12) then make another resistance source of x*(12 - 2.5/12). The value x would depend on the amount of current the LED's can handle so my guess is that x would be relatively low, say 100 ohms. Put these two resistance sources in parallel between the 12 volt source and the LED and you've got a 12 to 2.5 voltage divider to run your LED.

[fishing addict]

Tanseys,
thanks for the reply. this is exactly the info I was hoping to get. If it is to much work I'll just run them on batteries.

The LED I saw was a 5000mcd(brightness rating) 2.4 volt / 20 mA.

What does the 20mA mean? What resistance should I used based on this? Would I be able to run this bulb with AAA or AA batteries? Would it be bright enough based on the brightness rating?
I am still not certain I can make this work but will give it a try. Otherwise I will make them run on batteries and fix them to the wall if needed.
thanks again for the help so far.

[LOWinEYEin]

You can use this fomula:
Voltage=Current(amps) x Resistance(ohms)

The batteries are 1.5 volts each.
The 20mA is .02 of an Amp.

[Guest]

According to my quick calculations (man I've been out of school way too long to remember this stuff) you'd need a resistance source in parallel with the LED of about 157 ohms - call this R1. You'd then need another resistance source in parallel between R1 and the batter with a resistance value of about 757 ohms - call this R2.

Diagram
-------
__________________________
| | | |
Battery R2 R1 LED
| | | |
----------------------------

For practical purposes round up the values to R1 and R2 to the nearest hundred ohms. R1 = 200 ohms, R2 = 800 ohms.

Give it a shot and let us know how it goes.

[Guest]

ugggh!!

My diagram didn't come out very well, but hopefully it gets the concept across of how they should be connected up in parallel...

[IceC]

fishing addict

I was looking for LED lights for my portable and found a good HSOforum that has LED's and wiring kits for 12v. I think they would work good for you.

Shoot me an e-mail at [email protected] if you want more info, I'll send ya the link.

IceC

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Have an Ice day

[Jig stick]

IceE send me that link , ><sUMo>-------><> Jig Stick

[This message has been edited by Jig stick (edited 11-09-2003).]

[Wables]

Why don't you just wire 5 of them in series? It will be more efficient, because all of your watts will be used for lights instead of for a current divider, and you don't need to mess with any resistors.

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Wables

[fishing addict]

If wiring them in series would work I will do that. I plan on having 6 holes so that would work out great. what size wiring should I be using for this?

[can it be luck?]

Good lord! After reading all that, I'm buying 2 extra gallons of coleman fuel and mantles!

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http://groups.msn.com/canitbeluck

[Wables]

If you run 6 in parallel, that would be just over 2 volts each. You should do a test to see if that is enough voltage. As far as wire size, you are only talking aobut 0.020 amps. You could probably use heavy telephone cord or something on that order.

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Wables

[fishing addict]

Hey Wables
I'm confused,should I run them in parallel or series.You mentioned both in your post above. These bulbs are spendy so I don't want to short any.

[Kaz]

WhaTT. Series, so the total Volts DC is close to 12VDC. They are quite forgiving, so if your close to a total of 12vdc it should not blow the lights. Just for safty sake, add an exrta light in SERIES...Kaz

[Wables]

Arghhhhh! I meant to say series. Sorry about that.

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Wables

[walksonwater]

Hey!

I had an idea for hole lights. I picked up a few License plate lights and I'm planning on mounting them under my floor. My shack will be 9" off the ground so I have plenty of clearance and the lights are designed to stand up to outside weather. These are RV license plate lights so they are a bit bigger than an automobile plate light.

If you don't have the room under the floor you could always mount them on a piece of wood with a hing, then when you auger your hole out you just flip them up out of the way.

Just a thought.
Walks

[LOWinEYEin]

If you run it in parallel, You will blow the bulbs, because you will have 12 volts across each bulb. Run in series, put resistors first-Neg side, get the voltage as close as possible to the rating, the run the bulbs in parallel.

I would use a SOLID copper phone wire. Most are rated for 50 volts will work fine. and cheap

[This message has been edited by WhaTT! (edited 11-12-2003).]