LED Lights and Garage Door Opener???
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From: Michael A. Terrell on 14 Apr 2010 17:17 John Larkin wrote: > > Next we'll have expensive LED bulbs that "last up to 100,000 hours" > with crappy electronics. Nearly all the green LED traffic lights in > San Francisco have failed, in interesting patterns, and had to be > replaced. Only the greens, for some reason. I see a lot of failing red ones around here, along with the green. Some have already been replaced once, when over half of the LEDs went dark. It's interesting to look at them through the tinted top edge of the windshield. They sure don't match them. Their intensities vary all over the place. -- Lead free solder is Belgium's version of 'Hold my beer and watch this!'
From: Don Klipstein on 15 Apr 2010 01:13 In article <q9dbs5hsep3nihtv1f4uf9k1n5i7l6hqlb(a)4ax.com>, PeterD wrote: >And sweat the day when you can't get incandescent light bulbs any more >because you've been told that they are too inefficient! > >I'm sure we're going to see a sharp rise in residential fires in the >next 10 years, too... Mostly due to cheap chinese CFL lamps failing >when used in locations that are totally inappropriate, a move forced >by those who "think" they know best for everyone. The incandescent ban taking effect in stages from January 2012 to January 2014 has a set of loopholes wide enough to reroute the Mississippi river through, in my words. http://members.misty.com/don/incban.html (I did hear recently that part of what I thought the 2012 stage was is now set to take effect in January 2013.) Sadly, some incandescents will be replaced by some loopholers that are even less efficient than the ones being banned (rough/vibration service and traffic signal). Meanwhile, most residential usage of motion sensor lights that I see uses reflectorized R or PAR or BR floodlight and spotlight incandescent lamps, which are exempt from the 2012-2014 bans. These light fixtures (typically outdoors in my experience with residential use of motion sensor lights) appear to me to be the worst place for CFLs that I can think of at this moment, except for use in ovens. (And appliance lamps are another exemption from the 2012-2014 ban.) Other exemptions include tubular bulbs of showcase and refrigerator and exit sign types, globular bulbs of decorative and vanity types, flame-shaped bulbs used in chandaliers, ones with design voltage outside the range of 110-130 volts (even if only outside to an extent to hold up in a court case), and ones with light output outside the range of 310-2600 lumens (I am guessing possibly both at 120 volts and at their design voltage that is in or at one end of the 110-130 volt range). This means that low voltage incandescents including automotive incandescents and most incandescents used for indicator lamps, all common 120V incandescents of wattage 20 watts or less, and the vast majority of 25 watt 120V incandescents are exempt. Some 150 watt 120V incandescents and most 120V incandescents 200 watts or more are exempt on basis of producing more than 2600 lumens. Incandescents with bases other than E26 and E27 are exempt from the 2012-2014 USA ban. That alone covers pretty much everything of wattage 7.0 watts or less (already exempt on basis of luminous output), the vast majority of low voltage incandescents including automotive (at least generally already exempt on basis of design voltage or luminous output or both), a majority of halogen lamps, and nearly all projector lamps. (Many projector lamps are also exempt on basis of producing more than 2600 lumens, and a few are also exempt for being designed for design voltage of 82V requiring a diode in halfwave rectifier manner when powered by 120 volts AC.) Incandescents exceeding an energy efficiency standard that can be met or exceeded by good usage of "HIR technology" are exempt. Philips has one or more likely two already on the market for over a year including at Home Depot, as for ones that are exempt from the 2012-2014 USA incandescent lamp ban on basis of energy efficiency and for no other reasons. These would be Philips "Halogena Energy Saver". The one producing 800 lumens from 400 watts is exempt according to all sources that I have run into. The one producing 1600 lumens from 70 watts is exempt according to most but not all sources that I have run into. I hope I said enough already, although it appears to me that the USA 2012-2014 incandescent lamp ban has probably around 10 to a dozen, possibly more, get-arounds (mostly lesser such as "plant grow lamp", colored lamp, blacklight incandescent, bug non-attracting light, infrared, left-hand-thread screw base, marine, at least 4 others) that I did not mention above and that I do mention in above-mentioned: http://members.misty.com/don/incban.html - Don Klipstein (don(a)misty.com)
From: Don Klipstein on 15 Apr 2010 02:28 In article <4BC630D4.4812E944(a)earthlink.net>, Michael A. Terrell wrote: > >John Larkin wrote: >> >> Next we'll have expensive LED bulbs that "last up to 100,000 hours" >> with crappy electronics. Nearly all the green LED traffic lights in >> San Francisco have failed, in interesting patterns, and had to be >> replaced. Only the greens, for some reason. > > I see a lot of failing red ones around here, along with the green. >Some have already been replaced once, when over half of the LEDs went >dark. It's interesting to look at them through the tinted top edge of >the windshield. They sure don't match them. Their intensities vary all >over the place. My experience with LED traffic signals in Philadelphia and suburbs thereof is that the LED ones are showing their superiority. Please keep in mind that Philadelphia gets more extreme high temperatures than much of Florida. I have already lived through merely a July 1995 day in Philadelphia fair-chance getting hotter than Miami was ever officially noted to have achieved, some chance tying Miami's record high temperature in combination with dew point that is high even for Miami! (PHL airport or closest-to-there official weather station determined that at 4 PM "local time" July 15th the temperature was 102 F [peaking that day at a slightly different time at 103 F.]) (I have a tale or 2 to tell about atmosphere temperature at 102 F, and some cause to discount much-hotter)... - Don Klipstein (don(a)misty.com)
From: Hammy on 15 Apr 2010 07:01 On Thu, 15 Apr 2010 06:28:47 +0000 (UTC), don(a)manx.misty.com (Don Klipstein) wrote: > My experience with LED traffic signals in Philadelphia and suburbs >thereof is that the LED ones are showing their superiority. > > Please keep in mind that Philadelphia gets more extreme high temperatures >than much of Florida. I have already lived through merely a July 1995 day >in Philadelphia fair-chance getting hotter than Miami was ever officially >noted to have achieved, some chance tying Miami's record high temperature >in combination with dew point that is high even for Miami! > > (PHL airport or closest-to-there official weather station determined >that at 4 PM "local time" July 15th the temperature was 102 F [peaking >that day at a slightly different time at 103 F.]) > > (I have a tale or 2 to tell about atmosphere temperature at 102 F, and >some cause to discount much-hotter)... > > - Don Klipstein (don(a)misty.com) Municipalities in northern climates that converted to LED traffic lights are having to send work crews out to de-ice them. The LED's don't radiate enough heat to de-ice themselves.
From: Martin Brown on 15 Apr 2010 07:17
Hammy wrote: > On Thu, 15 Apr 2010 06:28:47 +0000 (UTC), don(a)manx.misty.com (Don > Klipstein) wrote: > >> My experience with LED traffic signals in Philadelphia and suburbs >> thereof is that the LED ones are showing their superiority. >> >> Please keep in mind that Philadelphia gets more extreme high temperatures >> than much of Florida. I have already lived through merely a July 1995 day >> in Philadelphia fair-chance getting hotter than Miami was ever officially >> noted to have achieved, some chance tying Miami's record high temperature >> in combination with dew point that is high even for Miami! >> >> (PHL airport or closest-to-there official weather station determined >> that at 4 PM "local time" July 15th the temperature was 102 F [peaking >> that day at a slightly different time at 103 F.]) >> >> (I have a tale or 2 to tell about atmosphere temperature at 102 F, and >> some cause to discount much-hotter)... >> >> - Don Klipstein (don(a)misty.com) > > Municipalities in northern climates that converted to LED traffic > lights are having to send work crews out to de-ice them. The LED's > don't radiate enough heat to de-ice themselves. This seems unlikely. LED traffic lights are efficient but to that extent there is still enough waste heat at least in the UK up to latitude 55N. It must take exceptional conditions for snow to accumulate on them. In the US there is already a fairly simple piece of bent metal solution for wind blown snow clogging up the sun visor cowling. http://www.ledsmagazine.com/news/7/1/4 Regards, Martin Brown |