Cold Cathode lighting

Printed From: the12volt.com
Forum Name: Lights, Neon, LEDs, HIDs
Forum Discription: Under Car Lighting, Strobe Lights, Fog Lights, Headlights, HIDs, DRL, Tail Lights, Brake Lights, Dashboard Lights, WigWag, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=57730
Printed Date: May 06, 2024 at 10:23 AM

Topic: Cold Cathode lighting

Posted By: Jknight
Subject: Cold Cathode lighting
Date Posted: June 15, 2005 at 4:33 AM

I'm interested in using these for lighting a plexiglass panel, I curious if this is the best idea? I've just started to look into leds, but I'm still a little confused about the resistor/ohm/viewing angle. I've tried to find info with little success finding plain english explanations. Any help would be greatly appreciated

p.s The panels will be 26"x16 and 16"x16" if that helps

Replies:

Posted By: Theshadow27
Date Posted: June 15, 2005 at 3:04 PM

LEDs can be confusing, but check https://www.metku.net/index.html?sect=view&n=1&path=mods/ledcalc/index_eng before you totaly give up.

Cold cathodes work fine in cars as long as you keep the vibrations down. your best bet would be to take the bulb out of the plastic tube that it comes in and glue it directly to the edges of your pannel.

the commonly avalible CCFL (cold cathode flourecent lamp) are designed for computers, and do run off of 12v. they are 300mm long (~12"), and one inverter can run 2. that means that to surround the edges of your pannel you would need 6 (3 kits) for the first pannel and 4 (2 kits) for the second pannel. you can get cheap CCFLs here: https://xoxide.com/coldcathodes.html

they cast a totaly diffrent type of light then LEDs, it is much brighter and more uniform. but compared to a standerd automotive neon - it is still nothing.

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Posted By: methinfinity
Date Posted: June 22, 2005 at 2:44 AM

sup jknight,

just did a job using 2 x ccfl's to light up plexiglass measuring 600mm x 300mm. give me ya email and i'll send ya some pics. can only upload small pics on here.

Posted By: nowlater123
Date Posted: June 29, 2005 at 12:44 AM

Here is another LED resistor chart you can use:

It is best not to drive the LED at the absolute maximum rating from an unregulated source.
These Values are for driving Single LED's only; LED's wired in Series or Parallel require different values.

Desired Voltage Desired Current Source Voltage Resistor Value

3.3~3.5v                20mA                    12V                      470 ohm .25W

3.0V                       20mA                     9.0V                     330 ohm .25W

3.5V                       20mA                     9.0V                     330 ohm .25W

3.0V                       20mA                     5.0V                     120 ohm .25W

3.5V                      20mA                      5.0V                     82 ohm .25W

3.0V                      20mA                      4.5V                     82 ohm .25W

3.5V                     20mA                      4.5V                     56 ohm .25W

3.0V                     20mA                     3.0V                     0~1 ohm .25W

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Kenwood all the Way!