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Marquee light is way too bright. Can I wire in a resistor to dim it?
justinjstark:
I just installed the marquee in my cab and the led light strip is way too bright. Looking at the marquee is like staring into the sun. :dizzy:
I think this is the light strip I installed.
I need to make the light dimmer. Can I wire a resistor into the power line to make it dimmer? I don't know anything about this. What kind/size of resistor? Is there a better way?
...next time I will install a dimmer light
MonMotha:
Looks like you should be able to use a resistor, yes. Not much electrical data posted on these things, but one comment gives the current consumption at ~300mA.
Try about a 15-22 ohm resistor. It'll dissipate ~1-2W, so get a 3-5W resistor, and be aware that it'll get pretty toasty. If you can't find a 3-5W, you can wire up 5 75 ohm 1/2W resistors in parallel to get a 15 ohm, 2.5W capable bundle. These should be available at radio shack. Any type of resistor should work in this application, including wirewound.
You could also just try hooking them up to a 9V or 5V power supply. That will dim it substantially. I'd recommend trying this before messing with resistors.
justinjstark:
--- Quote from: MonMotha on February 14, 2011, 02:42:05 am ---Looks like you should be able to use a resistor, yes. Not much electrical data posted on these things, but one comment gives the current consumption at ~300mA.
Try about a 15-22 ohm resistor. It'll dissipate ~1-2W, so get a 3-5W resistor, and be aware that it'll get pretty toasty. If you can't find a 3-5W, you can wire up 5 75 ohm 1/2W resistors in parallel to get a 15 ohm, 2.5W capable bundle. These should be available at radio shack. Any type of resistor should work in this application, including wirewound.
You could also just try hooking them up to a 9V or 5V power supply. That will dim it substantially. I'd recommend trying this before messing with resistors.
--- End quote ---
I tried connecting the light to the 5V power and then it is so dim you cannot see it at all through the marquee art.
Is there a 9V connection anywhere on an ATX PSU?
mgb:
I'm not sure this will do much, but what about the possibilty of putting another layer of something like a wax paper behind your marquee in order to better diffuse the light.
justinjstark:
--- Quote from: mgb on February 14, 2011, 08:45:56 am ---I'm not sure this will do much, but what about the possibilty of putting another layer of something like a wax paper behind your marquee in order to better diffuse the light.
--- End quote ---
This could work.
One thing that bothers me is that, while the marquee colors match beautifully when the marquee light is off, the marquee colors get a bit orange and don't match the cab so well when the light is on. Maybe I could find a brown, semi-transparent material to put behind the marquee graphics. Any ideas what I could use? I will try to find a hobby store around here this afternoon.