LED's

This is the place for any magazine-related discussions that don't fit in any of the column discussion boards below.
Post Reply
Will
Posts: 310
Joined: Tue Feb 11, 2003 1:01 am
Location: Katy Texas
Contact:

LED's

Post by Will »

I want to investigate using LED's as an actual light source e.g. for a traffic light - Considering light output vs dissipated power, what are the best LED's to use ? An example of actual mcd vs watts would be helpful. Thanx in anticipation
BB
User avatar
Dave Dixon
Posts: 436
Joined: Thu May 01, 2003 1:01 am
Location: Wichita, KS
Contact:

Re: LED's

Post by Dave Dixon »

Will,
Here's a site that has some info on various
voltage/wattage LED Traffic Signal Lights.
I hope this helps.
Ledtronics Traffic Signal Lights (LED)
Dave
User avatar
Chris Smith
Posts: 4325
Joined: Tue Dec 04, 2001 1:01 am
Location: Bieber Ca.

Re: LED's

Post by Chris Smith »

SuperBright Leds .com
User avatar
jollyrgr
Posts: 1289
Joined: Thu Jan 03, 2002 1:01 am
Location: Northern Illinois
Contact:

Re: LED's

Post by jollyrgr »

The US Department Of Energy has this information:<p>http://www.osti.gov/energycitations/pro ... i_id=55520<p>The above document is a bit old and comments that Green LEDs do not meet current standards. That was true back in 1994 when the document was written. Since then green LEDs have been developed that can be used in traffic lights. In fact Portland Oregon installed LEDs in their Red and Green traffic lights.<p>http://www.urbanicity.org/FullDoc.asp?ID=428<p>(NOTE: I believe that there might have been a "less" left out of the forth paragraph. See the OUTAGESCHEDULES link in the tower light section below.)<p>Not only are the normal stop lights being replaced with LEDs tower lights beacons are being made with LEDs.<p>http://www.tower-pro.net/Articles/LED_B ... eacons.htm<p>
And then there is this site. (Note how it says that the LED tower light uses 10% of the energy of the incandescent light.)<p>
http://outageschedules.beradio.com/ar/r ... _lighting/
No trees were harmed in the creation of this message. But billions of electrons, photons, and electromagnetic waves were terribly inconvenienced!
Dean Huster
Posts: 1263
Joined: Wed Dec 05, 2001 1:01 am
Location: Harviell, MO (Poplar Bluff area)
Contact:

Re: LED's

Post by Dean Huster »

I dunno why they'd use LEDs for tower lights (except maybe for the always-on variety) rather than the current xenon white or red lens covered variety that can punch through a lot more darkness and fog.<p>I haven't seen any new traffic lights going in that aren't the LED variety in our area, and I live in Podunk, Missouri.<p>I don't know why the green has always been a problem for traffic lights. They insist that the "green" be shifted toward the blue so that color-blind folks can tell the difference between red and green. Seems to me that the fact that red is always on the top (except for demented cities that run their traffic lights in a horizontal direction) should take care of that situation. Besides, if the traffic in front of you is going from left-to-right or vice-versa as opposed to the same direction as you're going, it should be an indicator that the light is probably red. :) <p>Now, if you look at railroad signal lights, when they're green, they're GREEN. No blue in them at all. They don't hire color-blind engineers.<p>Dean
Dean Huster, Electronics Curmudgeon
Contributing Editor emeritus, "Q & A", of the former "Poptronics" magazine (formerly "Popular Electronics" and "Electronics Now" magazines).

R.I.P.
Will
Posts: 310
Joined: Tue Feb 11, 2003 1:01 am
Location: Katy Texas
Contact:

Re: LED's

Post by Will »

Thanks guys - A veritable cornucopia of information which easily fulfilled my needs.
BB
Post Reply

Who is online

Users browsing this forum: Ahrefs [Bot] and 13 guests