Field Test: 24-LED “Light Bulb”

[jerry i h]

I got one of these at the local Ace Hardware. Unfortunately, there was no packaging since it was a small cardboard shipper with a bunch of "bulbs" in it, so I cannot tell you what the name is, or what the specs are. However, I am reasonably sure that this one is representative of other, similar other "bulb" thingies. The regular price was $8.95 (to answer your next question, I had a coupon).
It has 24 x 5mm LED's mounted on a rectangular column, 6 per side. My main concern was the light pattern: surprising, the light was reasonably homogeneous; at a couple of feet, there were noticeable striations, but beyond that was remarkably homogenous. The power consumption I forget, but is 1 or 2 watts. My rule of thumb is to take an LED's watt consumption and multiply by 5. To check this, I took out the LED bulb and put in the 7 ½ watt bulb from the refrigerator: the LED was brighter, but by only a small margin.
Wait: before you say junk, it is quite useful, if only for specific applications rather than a general bulb replacement. No, you cannot use it to illuminate a room: not only is it really weak, it has a strong, sickening, blue tint. But: it does supply surprising good ambient, security, or accent lighting. Think about: the bulb that is always on in the hallway for people who traipse to the bathroom in the middle of the night, the porch light, the walkways on the side of the house, or the baby's room. The good light extends to about 6 feet; beyond that, it is ambient level only.
Considering the fact that this beastie only sucks up a watt or so, you get a lot of light for your watt-hour-dollar.

 

[blasterman]

you get a lot of light for your watt-hour-dollar.

Provided the driver lasts more than a few hundred hours.

The problem with these type of bulbs, as we've discussed many time in the fixed lighting forum, is they are typically built from 'jewelry class' LEDs and use absurdly unreliable drivers. That's the reason they are so cheap. I hope this product is an exception and gives your money's worth, but my experience with shower-head type bulbs makes me skeptical. Good review in any case.

For $30-40 you can DIY something that will last a very, very long time, be orders of magnitude brighter and have drastically better light quality.

 

[jerry i h]

Actually, it is not a showerhead, but a long, rectangular column (dang; wish I had a webcam), and 6 LED's on each side. The entire thing is encased in a textured plastic tube 3 inches long.
I forgot to add my own snarky comments about my skepticism about the long term reliability. The 5mm's seem to be overdriven, so let's estimate a lifetime of 1000 hours. If you have it on 24x7, you will have to replace it every 6 weeks. I use mine a few hours a day, so my lifespan is, maybe, one year. I'll let you know.
If I were half the flashaholic I pretend to be, I would have bought 2: one to use, one to dissect and measure and study.

 

[Light Sabre]

I bought some of the Lights of America shower head 120vac light bulbs at Walmart. They used 5mm LEDs and had a blue tint to them. They didn't even last 6 months. Some of them were half brightness by then. Some of them died . Learned my lesson on this type of light bulb. Fortunately I got all my money back. Told the store manager to get them off the shelves. That they were absolute junk.

 

[LEDninja]

The interesting thing about the bulb in this thread is the LEDs fire out the sides. Like this one. Usually the light comes out in the forward direction only.

I gave up on 5 mm LED based bulbs some time ago.

I ran 1W warm white bulbs as nitelites for about 3 years. One in the kitchen, one in the bedroom. Still going strong until...

I replaced them with a single 2W Cree in the hallway.

 

[LEDAdd1ct]

I do not mean to derail the main topic, but:

LEDninja, the tint on the globe hanging from your hall ceiling is beautiful! Is that the two watt Cree you linked to in the second link, hanging in your hall? If so, I may have to try one! The warm white version, yes?

 

[blasterman]

I gave up on 5 mm LED based bulbs some time ago.

Generally speaking, when you move up to 1 and 3 watt LED bulbs there is an increase in quality, although there is still quite a degree of durability variance. The emitters are obviously more robust than the typical 5mm 'toy class' type, but a crappy driver will still roach them. If forced to buy retrofit bulbs I'd certainly start with 1-3 watt versions, and preferably a name brand emitter.

Not quite sure what the facination is with 5mm 'beehive/showerhead' lights given their know reliability problems. The more we buy them, the more will be produced at the same quality level {sigh}.

Warm White Crees put out 'superb' light.

 

[LEDninja]

I do not mean to derail the main topic, but:

LEDninja, the tint on the globe hanging from your hall ceiling is beautiful! Is that the two watt Cree you linked to in the second link, hanging in your hall? If so, I may have to try one! The warm white version, yes?

2nd link - warm white.

I am not sure if my crappy <$100 camera got the tint right in the dim light. The colours are more saturated than to my eye.
Easytin is using 2 of them in his range hood. Follow his link in this thread. Notice his picture shows a lot less yellow.
http://www.candlepowerforums.com/vb/showthread.php?t=221246

 

[LEDAdd1ct]

Thank you!

 

[jerry i h]

Uh, oh; spoke too soon . Dang, it was a nice little light: for only a watt or two (actually 5, I think), I got nice light that was reasonably homogenous. I was not keeping exact count, but I think I got about 50 to 75 hours of service.

OOC, and using my high school electronics knowledge (always dangerous), I took it apart. I discovered that the plastic capsule just screws off. The PCB is held in by 2 small screws. It has a full-wave bridge rectifier, a 3K film resistor, and all 24 LED's are hooked up in series. If I calculate right, each LED gets 5v and 40ma. I did a little poking around with my meter: I got an open circuit across the bulb base, but could not find the open circuit. I checked the rectifiers, the LED cluster, and the resistor, and their solder points, but everything seems to check out. I'll do a little more poking around, and let you know what I find.

 

[bhvm]

These 5mm are strictly toy/Decor grade LEDs and Should NOT be used for illumination anyday!!

At 5v,40mA they're SEVERELY overdriven...You porbably lost all the LEDs mate..