Young Artist with question about LED's for installation

[SX0T]

Hi, I am a young artist (25) and I am in the conceptual stages of a piece I want to make, but have a few questions that require the aid of some knowledgeable electricians. Hopefully I can present my project and get some answers without too much confusion.

What I am looking to do is find a way to suspend a tube light (fluorescent, LED, whatever I can use or works best) in space using string. The problem, is that I want it to be lit, but not have to be attached to any sort of huge fixture like the ones on my ceiling that typically get long tubes put into.

Is there a way to power a tube lightbulb, (florescent, LED, or otherwise) without it being attached to a fixture, and without some crazy wiring that would need to be done.

For reference, I have a picture of the general idea that I am trying to convey:

So, I need to know - is there a way to power an LED Tube light (or even a Fluorescent, I just assume it would be easier with LED) without a huge ballast using some kind of battery, or even a regular plug for a socket on a wall?

If so, how?

I should also note, in case this matters, that I would be covering the tube with a colored light gel to color the tube a very specific color.

The closest I have found is something like this http://www.batteryoperatedcandles.n...k=gdfV2875_a_7c73_a_7c182_a_7cacolyte_d_23500,
which is battery powered (3 AA) but frankly, it looks kinda dumb and the tube isn't as large or bright as I would like

 

[yellow]

when depending on battery power ...
size,
output power,
runtime.
these are the 3 criteria You try to mix, choose 2 of them
;)

An idea (runtime problem, when You want to use batteries):
get a flashlight,
get a plastic tube, best if milky transzulent, in the size/lenght You want.
(probably put a slightly "magnifying" mirror on top, to use even more light; that otherwise would just "escape" there)

test "Setup":
mulitlevel light: http://www.4sevens.com/product_info.php?cPath=22_56&products_id=362 (multilevel, for You to choose brightness)
traffic wand: http://www.4sevens.com/product_info.php?cPath=22_27_38&products_id=642 (shorter than You will want, but to get the image)
even smaller "wand": http://www.4sevens.com/product_info.php?cPath=22_27_38&products_id=339


or:
get uv active pp sticks/tube
use UV-led


PS: pls resize Your pics to 800*600 max

 

[Paul Baldwin]

Hi,
why not use the wires that hold it up as the string if it's only an art project? Or even bare stiff wire like you see on low voltage halogen but thinner, it'll be low voltage dc so completely touch safe.

 

[SX0T]

So I guess to rephrase the question in a more effective way, I'll start here. I included a drawing of what I am shooting for here in the end with 2 possible solutions (unless something better comes up) One solution on the left is to plug the light into a wall. Second solution on the left is to plug it into some sort of battery. There may be other solutions (ie smaller batteries, or whatever). What I want to do is suspend these 2 fluorescent or LED tubes at different degree's of angles from the ceiling (which is why there cannot be a large ballast mount). I want them to be about the size of a regular fluorescent tube (same in circumference around and about 36" in length). I have also found a link to something that may work, so I'm wondering if this will spark any better ideas.http://www.bosspaint.com/Plain_LED_Light_Strip_36_Inches_Long_RED_or_Blue_p/4.htm

I'm wondering if something like that, that can be plugged into a wall (these can only use a cigarette lighter adapter can be slid down into a frosted tube.

Maybe this new info will spark some more ideas - and thanks for all the help I've been given so far. Here is the drawing:

 

[lyyyghtmaster]

If you use LEDs, depending on the color you want you may be able to do it without gel. This would improve efficiency since you wouldn't be generating some colors only to filter them out with the gel. You may need diffusion though to keep from seeing each individual LED.

Does the piece get viewed from many angles? If not you could perhaps get away with a single strip of Pirahna-type wide-angle LEDs facing in one direction. If it's displayed in the round you would probably need two or three strips facing 180degrees or 120degrees from each other. There'd have to be an LED every 1 to 1.5 inches or so if you wanted to have any hope of light uniformity. That's a lot of LEDs to wire. You may be able to find suitable strips pre-made on the Web, and those often run on 12 VDC.

Having a traffic cone be the tube would be much easier, but those taper. Also it would take a powerful LED to come near the output of even a filtered fluorescent tube. Put a 3 watt high-brightness (power) LED, with suitable narrow beam optics, on each end of a tube of medium-heavy diffusion. You would need heatsinks, and those are bulky and may be obtrusive in your application. Try mounting each LED with optic inside a 1.5" copper pipe endcap. That would kind of look like the end of a regular fluorescent tube and may be enough heatsink for you. The diffusion is too floppy so contain it inside a polycarbonate fluorescent tube protector (sold at home improvement stores). To make this work electrically you would need approximately a 7.5volt, 1 amp regulated wall wart-type power supply and a 0.82 ohm, 1 watt resistor. Everything gets wired in series, observing polarities. The resistor will get kinda hot, so mount it by itself away from the LEDs and any meltables.

I realize you will probably need more help than this to get it done, but the foregoing is a rough gameplan of a couple possible solutions using LEDs.

Have fun! :D

 

[SX0T]

I feel like I'm getting somewhere, but I'm still pretty lost about how to power all of these ideas.

 

[Ken_McE]

I feel like I'm getting somewhere, but I'm still pretty lost about how to power all of these ideas.

Your options:

1.) Make it battery powered (EL or LED), build batteries into tube, change daily.

2.) Make it DC, have battery hidden in ceiling, wall, decorative box. Instead of strings get very thin wire, use very thin wire to hang fixtures and run power simultaneously.

3.) Make it AC, run lead cord to outlet. Try to make lead cord(s) inconspicious.

4.) Have tight focus light hidden off to one side. Shine light on tube.

5.) Use fiber optic line(s) to hang tube. Send light through line.


I'd say #2 is the easiest.

 

[mahoney]

In the interest of suggesting something far more complicated than it needs to be...you can get fluorescent tubes to light without any wires connected to them at all, as long as they are in close proximity to a Tesla coil.

Seriously though, if you want to use LEDs in a frosted tube, you can use the wires suspending the tube to get the power to the LEDs, then you won't need a power cord dangling from one end of the tube, it will go to the mounting points instead. But you will need to do some experimenting to see how many and what type LEDs you want to use. Got an electronics geek type friend with a pile of LEDs on their workbench? Once you have some idea about how many, it will be a lot easier for folks to make helpful suggestions about how to drive the LEDs

If you want an easy way out, there are products like rope light and LEDs by the foot that could be slid into a sanded plastic tube, and these usually come wired for a specific input voltage, so long as you stay within the manufacturer's length increments.

 

[Paul Baldwin]

Are there existing lights in the room the artwork will be suspended in? You could maybe use something like this to provide ac power from the ceiling to your power supply to minimise messy looking wiring? http://www.fruitridgetools.com/stor...aspx?sfid=136763&i=234038936&mpid=8171&dfid=1

 

[Helmut.G]

Ken_McE is right, powering through thin wires would be the easiest way.

If you want no wires (eg because you want to use nylon cord thats hardly visible) build batteries into the tube. the batteries need to be changed periodically, depending on the brighness you want, how much money you can spend on efficient LEDs+circuit (better LEDs will obviously be more expensive, but you can also increase efficiency using more LEDs (again more expensive) driven with less power) and how much room there is for the batteries (bigger batteries of comparable type will last longer)

use colored LEDs if you can afford it. a fluorescent tube would probably be cheaper but you can't build batteries into the tube and you need to find a low-voltage, dc powered one to make the wire thing safe.

If you want ultra-scientific, ultra-cool and expensive, go for the wireless-powered fluorescent tube mahoney has mentioned :devil:

Inform yourself what kind of LEDs there are, ie high power ones, low power ones, concentrated beams or wide-angle ...

 

[HarryN]

Hi, it sounds like you need some technical support to deal with the specifics of the lighting part. It is pretty common for artistic thought and engineering to come together with solutions for things like this.

There are quite a few people around CPF that could help if you post where you are located. I would be happy to help for instance, as I do some custom lighting work, but it would need to be at least partially a business arrangement, not necessarily up front money though.

Feel free to send a PM to me and we can work through it.

 

[SX0T]

Ken_McE - your list looks awesome. Thanks for being a little more simplistic with me - it helps
I think options 1, 2 and 3, sound the most realistic for me. In #2, which you say is the easiest, are you talking about fluorescent tubes? or still LED?

mahoney - I'll get back when I know about how many LED's. But I do know that each of these tubes needs to be about 36" long - and the light effect that I want is something of a lightsaber kind of glow. I want it to be a pretty even light that is coming from them - and I was actually thinking just recently about LED strips and just sending them down a frosted tube and powering them with whatever you can power LED strips with (I don't even know how they work).

Helmut.G - I know it is hard to say without knowing how many LEDs and what I am using to put these things together, but battery powered, any idea what kind/size batteries I would need to power 36" of LED's to create that even glow? And about how often they would need to be replaced? This may not be a question you can answer, but thought I'd ask.

HarryN - thanks so much for the offer, I am located in Illinois for anyone who is interested. I know many artists who collaborate with engineers on this stuff (my brother is a computer engineer and I've already talked to him about all this stuff as well). At this point, I am really looking to learn how to do some of this myself. I like my work to be very hands on and educational which is why I have spent the past 3 weeks already posting on message boards, making phone calls, etc. trying to get enough info to give myself a start. I really appreciate the offer though - it is great to know that there are people out there willing to help artists (we often find ourselves a little lacking in all these outskirt areas of our research).

 

[HarryN]

Ok, well the easy way to learn is to start reading, and buy some leds.

Given that your project is more artistic in nature, I suggest you visit the site www.lumileds.com and download some data sheets on the rebel product. The reason I suggest them, is the very wide color option availability, for example, 17 part numbers just for different options of white, plus the colors.

The general nature of LEDs is pretty similar, so once you read in depth about one version, the others are similar enough to just translate the knowledge to that specific part, and Lumileds has really good data sheets.

After you read those a few times, buy about 10 of each interesting color and start making something. It really is a hands on kind of thing.

 

[SX0T]

Thanks HarryN

I also wanted to post this current conversation I was having on another board and get some sort of a response here from it maybe

I wanted to post over some information I was given on another forum and see what the response is.

COMMENT:

How thin do you want the strings to be? How long do the lights have to be on for?

You could either hide a big battery in the ceiling and, using LEDs, use the strings as wires. this would be low voltage and safe(not sure if it would pass like a government inspection or anything) to touch. You would probably want insulated wires but make them as narrow as possible.

You could put individual LEDs inside the tube, each one having its own button-cell battery. This would only run for a couple hours, and you'd need lots of batteries...

MY RESPONSE:
The strings would vary in length - I'm guessing 5-6 feet. Ideally the lights would need to be able to be on for a few hours a day for an extended period of time (if this piece were ever accepted into a show). I could make sacrifices to get it up and running for now, but then I would just have to re-figure everything out in the future.

So, are you saying that if I used like LED strip lighting and put it into my own tube, I could use wire that could also function as the support that leads up to a battery hidden somewhere in the ceiling?

And by "big battery" what are we talking here? Car battery? or is it something that would be custom built?


COMMENT:
Really the "big battery" can be anything that supplies you a DC voltage for the LEDs (those LED strips you linked were 12V) with enough current. You could use a car battery, a custom battery, lots of standard size batteries, OR something that plugs into the wall and converts the AC into DC, which would probably be the best choice, since you wouldnt have to worry about batteries at all and this type of converter is cheap.

The question is, how THIN are the strings supposed to be? I would imagine that the ideal solution for your project would be like fishing line or some other transparent, thin string. But if you can tolerate more width I think you could use wires both as structural support and power. We're not talking nearly as thick as, say, a lamp cord, but something like insulated 24 to 30 AWG. The diameter of 30AWG is 0.01 inches or 0.28 mm, and it can carry up to a rated 142mA. AWG rating table. series LEDs would need at most 20mA, so you can put 2 or 3 strings in parallel.

Keep in mind the 0.01 inches will not include the thickness of insulation, which will probably double or triple the thickness.
They make it in black. Actually, that particular insulation is probably thinner than what I just said. Try to find some at a hardware or electronics store perhaps and see if it'll fit the bill.

How many 36" bulbs are you trying to put up in this display? because that will affect the power supply that you will need.


MY RESPONSE:
Do I need to make sure that whatever plug I have that converts AC to DC is certain volt? Also - how do I make sure that it is able to be connected to the wires? (The only kind I've ever seen goes from the wall and has a plug for whatever device is using it (modems, dvd players, etc).

Ideally the strings would be almost nonexistent, but I know that is only a possibility if the tubes are somehow battery powered.

also, when you say 2 or 3 strings in parallel, are you talking about strings of the wire? Maybe I'm confused, but if the 30AWG can cary 142mA, and series LED's need at most 20mA, why would I need to parallel things? wouldn't the one wire be enough to power the whole series?

Thank you a bunch for your help so far, I finally feel like I'm getting somewhere with this stuff.


COMMENT:
I just looked again at those strips you linked. They try to sell a 12V car charger on the same page so I assumed they were 12V, but they are not. Looking at the technical specs page, they are 3V - 6V and 300-600mA. This is too much. You can probably easily find a 12V or 24V LED strip that will take far less current, which is what you'll need to make the wires as thin as possible. try shopping around. You might look into LED rope lighting. It is probably very easy to modify to suit your project, and it's long and cheap. If you can't find a 36" LED bar or strip that meets your needs, you can consider using 2 or 3 bars inside of each tube (3 12" bars), but again this might require triple the wire. Let us know what you find.

The 12V or 24V strip will also be convenient since most of the AC-DC converters are made for those voltages as well.




I was also told that using fluorescent tubes is probably not a good idea as the wires would be delivering a volt that could shock someone if the bulb or wire were touched on accident while someone was looking at the installation

 

[HarryN]

You would be pretty amazed at what can be accomplished with gas filled tube technology and a good glass blower. These guys can pull off some amazing stuff. That being said, it does take a high voltage supply to make it all work, and I have touched them before as a kid - but only once. :o

Most people expect modern stuff to be LED in order to be "cool / chic", so that is a factor.

You can buy AC plug wall adapters made specifically to drive LEDs off the shelf, so that is not a big deal. You can also get drivers that work from DC, its just a matter of what you want / need.

I would use wire that can easily handle 500ma at 100 volts potential even though it will likely be setup for no more than 30 volts in actual use. I suppose if you really want to push the "thin string" aspect, you could get away with a 500ma capable wire, non insulated and plan to run at no more than 24 volts. Even if it were touched, it would not be a serious problem.

What you are trying to do is pretty straightforward. Probably the parts could be ordered in one day and several proof of concept demonstration examples built in 2 - 3 days or less.

 

[SX0T]

HarryN

So a wire that is capable of 500ma and anything over 30 volts should be good enough to suspend and power whatever kind of LED's I end up using? Whether that be pre-bought LED strips or strips I've assembled? (I would probably stick to insulated just to be safe).

Also - AC plug wall adapters off the shelf? Is there anything I need to be extremely specific about when buying something to work with the LED's?

Any recommendations of reputable sellers online for LED's and this stuff or are my previous links heading in the right direction?

Thanks again for all the help, I finally feel like I'm getting a bit closer to a game plan.

 

[blasterman]

SXOT, you really need to look at cold cathode for this. LED wont deliver the smooth light source you describe. Look at Xoxide.com for examples.

 

[SX0T]

Those Cold Cathode's look great, and putting them into a larger frosted tube would work wonders I think.

However...I'm only seeing like 12-15" max on these. I need each of my two lights to be 36" in length.

 

[HarryN]

HarryN

So a wire that is capable of 500ma and anything over 30 volts should be good enough to suspend and power whatever kind of LED's I end up using? Whether that be pre-bought LED strips or strips I've assembled? (I would probably stick to insulated just to be safe).

Also - AC plug wall adapters off the shelf? Is there anything I need to be extremely specific about when buying something to work with the LED's?

Any recommendations of reputable sellers online for LED's and this stuff or are my previous links heading in the right direction?

Thanks again for all the help, I finally feel like I'm getting a bit closer to a game plan.

Well - no. What I specifically suggested is that you start by reading the data sheets, get some Lumileds rebels to play with, and these can be driven at something like 350 - 500ma to (most likely) get enough light for your project. You indicated that this is art work, not for bright lighting.

The wire could be as thin as the minimum for 500ma in terms of electrical capacity, but you need to engineer (or guesstimate) the wire size needed for the weight.

Please read carefully that I suggested that you buy an AC or DC driver specifically made for LED use. There are a variety of brands that a little searching will resolve.

Learning comes from trial and error, so expect to have a few errors along the way - that is normal.

 

[LukeA]

According to this chart, 30AWG copper wire is plenty to handle 350-500mA. (Chassis wiring is the appropriate column)