You have to stretch the definition of "white" light, since the theoretical limit for white light is about 250 lm/W for 100 % efficient electricity to visible light conversion (no component heating). "White" in this context means a spectral distribution even remotely resembling the black body radiation at some specific color temperature.
Of course, the theoretical maximum is 683 lm/W for 555 nm green monochromatic spectral line with 100 % conversion efficiency.
why wait? preheat.
-- ?? 100% natural --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
Possibly the largest prime number ever used for unit conversion. ;)
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 USA +1 845 480 2058 hobbs at electrooptical dot net http://electrooptical.net
I read the numbers off a box used by the Edison Company to sell subsidized CFLs. How much input is required to smelt tungsten?
"dave the TROLL"
** They are both out by very large factors.Google will put you straight, or a bullet.
FOAD.
"John Devereux"
** I am sometimes taken for a pom, cos I speak too well for some dinkum Aussie ears.And don't support the lunatic trolls here, it make you look even worse than them.
.... Phil
Thanks for that, useful.
-- Regards, Adrian Jansen adrianjansen at internode dot on dot net Note reply address is invalid, convert address above to machine form.
How very strange, i do not have any problem finding LEDs with reasonable CCTs
Try:
And i am sure there are others.
Maybe it is lamps which are troubling you.
See:
I do not understand not being able to find the LEDs or lamps you might want.
?-)
Dude, the color temperature of the phosphor is tested on a per lot basis and the phosphor is binned. Moreover it is probably well enough controlled to be on bin in the first place. The only production testing done is sampling to make sure that the resultant parts are within specification limits.
Test engineering used to be my gig.
?-)
As a matter of fact, a slightly radioactive environment is necessary for life to evolve. Cancer is a concomitant attribute of such locals. So yes, i do like it. Just not at Love Canal levels.
?-)
You forgot weed.
and a good steak!
One of these day, I need to empty out the bottom of my freezer and unplug the drain hole down there. Right now, the melt collects on the bottom of my freezer, where it re-freezes. I usually notice this when it reaches the height of the door and runs out in a puddle in front of the freezer... ;-)
I had the pan under mine slip out of the mount and leak all over the floor.
Mine is upright, SubZero. There's a "trough" in the back that guides the "frost" down to the pan. It got blocked by some crud, somehow, and spilled into the main chamber, then froze :-(
Fortunately I have a hot air gun for shrink tubing. ...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
A bigger problem is when the defrost timer fails in defrost mode with no power to the compressor, and the heating element on full time.
Careful... A lot of the plastics used inside fridges and freezers don't handle heat well.
OK, I finally got these 104 Lm/W LEDs in, and put 10 of them on a board. Very impressive, even at 10 mA. At 50 mA, you can barely look at them, and at 350 mA (the rated current) they are piercingly bright. I have a single 36" T12 fluorescent over my bench, and it is a good brightness. (These are rated at 2275 Lumens.) The LED array appears to be "twice" as bright illumination on the bench at only 10 W power input. Cree claims accelerated life tests rate the lamps at 95% or original light output after 60,000 Hrs at 350 mA and a fairly high temperature. I think I can keep them cooler than the test temperatures, no more than 50C. (The board they are mounted on barely warms up, but the LEDs themselves do get a bit warm to the touch.)
So, this is all looking very positive so far. I have to build the PWM current regulator circuit.
Jon
don't use PWM. do a linear or a switcher. pwm will just waste energy heating the LEDs.
-- ?? 100% natural --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
Do not forget a nice big diffuser to maximize and homogenize their output.
15 turn wire wound pot for the main feed circuit.
Make a precision current limit array so each lamp gets a discreet limiter that can handle what you intend to push. I'd use a wire wound for that too.
Or find a way to feed the whole thing with an old soldering iron station temperature controller.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.