LED lighting

[SonofSol]

The problem with LED's are many but the 5 biggest are:

1. Cost.

2. Efficiency is exaggerated and does not conform to NLI standards. As mentioned the problem is with the driver circuits and heat. You will see claims as high as 100+ Lumens per watt. When the ballast or driver power is included as with all other lighting, the efficiency is not much better than incandescent

3. Next on the efficiency hit list is LED's produce the highest output when they are cold. So when the measure the Lumen output with a very short pulse of a few milli-seconds so the light does not warm up. Once the light warms up in real use, the output drops considerable.

4. Last on the efficiency list is the directional nature of LED light and where they take the measurement. They measure on the lights focal spot. Move a few degrees in any direction and the light falls off the cliff. Great for flashlights and effect lighting, terrible for indoor area lighting.

5. Color Rendering Index. LED's CRI is horrible with an extreme amount of Blue light pollution.

The most efficient lighting one can use in your home is fluorescent T5 tubes which has a true 100 Lumens per watt and excellent CRI. Next in line is CFL of 60 to 80 Lumens per watt, and then LED with a real rating of around 30 to 6 Lumens per watt.

I concour
Additionally, depending on the driving frequency verses pure direct current some LED drivers actually create a strobing effect and or a noise, that may be audiable and also cause radio frequency issues as well. LED's have a very fast rise time, meaning they go from an off state to full on in very short time, by comparison a filament based lamp is like waiting for the stove to cool down.
These inherant idiocyncries give lamps there unique qualities, and should be factored in when given a particular application.
Seldome, other than the inexpensive LED battery powered flashlight (torch for our UK friends) are LED's driven directly without some type of additional circuitry.
Indeed it is when LED's went from indicator duty to the sighnage, and now general illumination role where the quest to boost the lumen output has created some very interesting challanges!

[SonofSol]

Retail Lighting?

[QUOTE=Demetriusalwyn;8127]Led Lighting is lighting which solely makes use of LEDs, small lights, often assembled in groups of 18, 21 or more in one led light bulb. However more lamps don

[Sunking]

The problem with LED's are many but the 5 biggest are:

1. Cost.

2. Efficiency is exaggerated and does not conform to NLI standards. As mentioned the problem is with the driver circuits and heat. You will see claims as high as 100+ Lumens per watt. When the ballast or driver power is included as with all other lighting, the efficiency is not much better than incandescent

3. Next on the efficiency hit list is LED's produce the highest output when they are cold. So when the measure the Lumen output with a very short pulse of a few milli-seconds so the light does not warm up. Once the light warms up in real use, the output drops considerable.

4. Last on the efficiency list is the directional nature of LED light and where they take the measurement. They measure on the lights focal spot. Move a few degrees in any direction and the light falls off the cliff. Great for flashlights and effect lighting, terrible for indoor area lighting.

5. Color Rendering Index. LED's CRI is horrible with an extreme amount of Blue light pollution.

The most efficient lighting one can use in your home is fluorescent T5 tubes which has a true 100 Lumens per watt and excellent CRI. Next in line is CFL of 60 to 80 Lumens per watt, and then LED with a real rating of around 30 to 6 Lumens per watt.

[Demetriusalwyn]

Led Lighting is lighting which solely makes use of LEDs, small lights, often assembled in groups of 18, 21 or more in one led light bulb. However more lamps don

[ed2kayak]

It looks very bright. Did you make it yourself? How many LED's?

[indalecio.feng]

Any recommendations for LED lights. I have 3 ceiling cans that I have CFL's (20 wt) now, that I would like to use LED in.
Thanks

Have a look my LED lamp. The long one is 1,2m. The shorter one is 90cm.

[Mike90250]

Hey, thanks for the info.

Yep, biggest problem is cooling the LED. Costco just had to to a big refund to folks who got LED bulbs, and the only lasted a couple of months.

[SonofSol]

LED's in ceiling can lighting

I worked in the LED business for the past 3 years, there are some strides in output per watt. This field is growing with great strides. The biggest problem is cooling.
We manufacture lights for aircraft, and while most of these were configured to run off of 28Volts DC we did make some for 120 Volts AC @ 400 Hz
The problem is current control with each LED or string of LEDs.
While it is true most white light LED's forward voltage is about 3.5volts the way in that the current is controlled varies a lot. There are many getting into this field but mostly it is the commercial applications is where you will find the "good stuff". These screw in LED bulbs for 120 VAC leave much to be desired and while a CFL may seem "low tech" they are still very good at converting watts to lumen's
Color temperature is another factor to look at in selecting any lamp other than a incandescent The lower the number, the warmer the color. (2700 K is very warm and pleasing)
White LED's are basically blue LED's with a phosphor dot that emits the white light (much like a fluorescent uses the UV spectrum to excite the phosphor coated tube.)
If your ceiling cans are purpose built to accept only a proprietary lamp (Bi or Quad pin) then you will be waiting a long time and would need to change out that fixture for another as these have their own (ballasts) control circuitry made just for the one lamp type. If they have a standard light bulb socket, you do have some options out there, although I have yet to see any that really "shine" pun intended.

[ed2kayak]

Any recommendations for LED lights. I have 3 ceiling cans that I have CFL's (20 wt) now, that I would like to use LED in.
Thanks