LED Lights Are You Ready?

[yyzdnl]

Received several different LED lights from Deal Extreme last night. Some of the newer LED lights are pushing the lumen's per watt ratios of the T5 & T8 bulbs. Of the bulbs I received the one I like the best is the E27 HA006 6W 128-LED 700-Lumen 4000K Warm White Light Bulb (110V). It has a real natural color and looks great in lamps and fixtures using the E27 socket.

Hard to say if it is hitting the specs it is listed at since I haven't had a chance to put it on the Killawatt & I don't have a light meter. They do look brighter and with a nicer color than the 14watt CFLs I replaced.

[john p]

Sunnyking I understand that its information you giving only.
I was just giving an example that they can be the best(in my opinion) to be used in some situations.
I think it be hard to find anything that can light up the whole perimeter of a building and use less than the 144 w im using.
Measured light and apparent light are different. A lot depends on how bright it seems by the colour of the light. As its well known that a green laser beam to the eye looks many times brighter than a red laser beam looks. but if you measure them they both the same intensity.
Sometimes figures get in the way of the facts.. but I didnt say that.

[Sunking]

John my only point here is LED may not be as efficient as you may have been lead to believe. It is just info and nothing more.

[john p]

they are made by CREE they operate on 12v DC(11 to 15 is ok)and can be connected without regard to polarity. available in 1w and 3w (6w is wasted) so the total draw is 7w and 9w ,availabe in narrow and wide angle. are direct plug in for MR16 s. get daylight or cool white NOT warm white, the colour of warm white is terrible.
I buy mine here from an electronics parts chain Jaycar.. a bit over priced I think but worth it in long term.

[Mike90250]

OK not doubting your figures BUT we have 16x3 w LED MR16 lights around the outside of my building/house that give excellent security light .....

What is mfg & model # of those ? I'm looking for something like that.

[john p]

OK not doubting your figures BUT we have 16x3 w LED MR16 lights around the outside of my building/house that give excellent security light from building to well part the outer fence,
Each 3w LED draws 9w at 12v 16times 9w =144w ,I be interested to know how this could be done on less power using any other lighting device ???
Our ice making room now has 6 of these lights that provides to our eyes(nothing instrument measured) more even and brighter lighting than the 4x 20w flourescent tubes we used previously The LEDs 6x9 = 54 w at 12v. the 4 flourescent lights ran of an inverter so inverter losses have to be added.
All in use now 3 years no failures ,same goes for other similar security installs I have done. All security lights run 10 hours every day of the year.
All of us are 110% happy with the LEDs.
Reasons. long term reliable, run direct off 12v battery, much harder to vandalize than flourescent tubes. give visually good bright even lighting.

[Sunking]

Well if so you might want to tap the brakes and take a closer look at the numbers and see what they mean before you shell 5 to 10 times more money for them over CFL and Florescent tubes. With all lighting the two numbers to look at are Lumens per Watt (L/W), view angle, and to a lesser degree light color temperature.

Lumens/Watt is the measure of the efficiency of a light and is really easy to grasp. It tells you how much light the luminaire produces for each watt of power being consumed. The higher the Limens per watt the better. For example 100 L/Watt is twice as efficient as 50 L/Watt. It is a 100% difference. The Lumens measurement is made at 1 meter from the light source in the middle of the view angle if less than 360 degrees. If view angle is 360 degrees the light is measured at 1 meter distance in any direction around the circumference of the source.

Next is view angle. All incandescent, CFL, and fluorescent tubes emit light 360 degrees around the circumference of the fixture, while all flood lights have a view angle or beam width where 140 degrees is typical. This becomes very important as you start to compare light sources which I will now demonstrate.


Ok one of the most efficient LED lights for sale today is PAR38 42 White SMD LED Flood Light Bulb, 1314WH-CV. The Specs are: Lumens = 650, Power = 9.5 watts, View Angle = 140 degrees. Just from the numbers we can ascertain the efficiency is 650 Lumens / 9.5 watts = 66 L/W. Sounds great huh as an old tungsten incandescent is only around 18 L/W. But wait a minute the view angle is 140 degrees, not 360 of an incandescent bulb. Factor out view angle and you end up with [140/360] x 66 L/W and you get roughly 26 L/W which is still better than an incandescent right. Problem is we are not comparing apples to apples as we would not use incandescent for a flood light. Assuming we are looking for a similar light color we would probable use Quartz Halogen which has an efficiency of 22 to 26 L/w or roughly the same efficiency as a LED flood light? Interesting huh?

[B][FONT=&quot][B]Take it another step let