On Fri, 02 Jan 2015 19:51:18 -0500, "Michael A. Terrell"
wrote:

I see a lot of LED traffic lights with groups of dead LEDs.

I haven't. Locally, we have some LED traffic and street lights. I
have yet to see one malfunction. However, it might be simply because
the traffic department is good about quickly replacing any failures.
Most LED lights include a remote monitoring feature.

I'm not sure what might be causing the failures that you've observed.
Any sign of overheating? Power glitches? Bullet holes?

Los Angeles Saves Millions With LED Street Light Deployment
http://www.forbes.com/sites/justingerdes/2013/01/25/los-angeles-saves-millions-with-led-street-light-deployment/
After 36 months of initial operation, for instance, high-intensity
discharge (HID) fixtures in Los Angeles recorded an average failure
rate of 10%; the average failure rate for LED fixtures, according
to the latest figures, is 0.2% (189 of 98,000 installed).

The one
closest to me is on the fourth red LED lamp in the last couple years and
already has some groups that are quite dim.

Got an IR temperature gun? Get as close as you can and get a
temperature reading. My guess(tm) is that it's running hot, even with
some blown lights.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558