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The Biggest Thing Since the Light Bulb

creebulb.com

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Re: The Biggest Thing Since the Light Bulb

#131

Post by jwr »

ars wrote: post #86
jwr wrote: post #77

We are still in the dark ages, though. Just consider: this "bulb" has to plug into the standard 110/230V AC electrical sockets. Powering an LED is nothing like powering an incandescent bulb: you need a constant current driver delivering a precisely measured DC current that, depending on the LED, is between 300mA and (say) 1.5A. The voltage you need depends on the number of LEDs in series, but assume 3.2V per LED. If…

24 (or 48) volts is still too high - so you would anyway need a power supply. And go too low on the voltage and the wires become so large as to be impractical. These types of smart active electronics are getting cheaper and cheaper. I really don't see much need to eliminate them.

24V is just fine for a string of up to 6 LEDs. Your comment leads me to think you haven't designed many switching regulators. You can drive up to six LEDs from 24V at 92% efficiency with 6 components (I have a device I've designed in front of me that proves it): one IC, an inductor, a resistor, a diode and two tiny capacitors.

Re: The Biggest Thing Since the Light Bulb

#132

Post by iSnow »

exodust wrote: post #117
iSnow wrote: post #99

Earlier quoted context omitted.

Thanks to noscript, I never even noticed.

You also wouldn't have noticed much of the content and interactivity you missed out on. Pages such as Comparison, and History are blank without javascript. Noscript is like leaving your TV on VHF even when digital works fine. Ok, so anyway, people complaining about bad design should blame the bad design rather than the platform it uses. Happened with Flash when people said "let's say no to annoying ads on websites, a…

>interactivity

Actually this is one of the reasons I use noscript. A lot of web site interactivity is completely annoying, so I only turn it on when the site is interesting enough - which is not the case here.

Re: The Biggest Thing Since the Light Bulb

#133

Post by urza »

ck2 wrote: post #3

This is huge if only because a LED bulb company finally put its warranty where its mouth is. Every other bulb, ie. the expensive Phillips bulb, only gives a 3-4 year warranty I'd definitely give this a try @ $10 It's also dimmer compatible which is a big plus for me with X10 control, CFL cannot dim. If this bulb does not operate for 10 years (based on 6 hours per day / 7 days per week of normal consumer use) from dat…

The bulb will probably operate in 10 years, but most likely it will loose its brightness over the years, because I doubt that it can be properly cooled..

Re: The Biggest Thing Since the Light Bulb

#134

Post by zokier »

ck2 wrote: post #130
zokier wrote: post #112

Earlier quoted context omitted.

Yes, but the point was that it would be far more optimal to have the control signals go directly to the LED driver circuitry instead of chopping up the mains voltage and hoping that the LED driver will handle it. Computer analogy: Imagine you would like to adjust the performance/power of your computer. You could plug the computer to a dimmer and then engineer the computer to adjust itself according to the dimmed main…

I don't think X10 changes the voltage on their dimmers, I think it's PWM I could be wrong.

Most dimmers, X10 based or directly controlled, are based on chopping the voltage not completely unlike PWM. They are called "triac dimmers". But irregardless how the dimming is implemented, the effective (RMS) voltage is changed. But in addition to lowering the voltage standard triac dimmers also create problems as the dimmed voltage waveform isn't sinewave anymore.

Re: The Biggest Thing Since the Light Bulb

#135

Post by dietrichepp »

ars wrote: post #81
dietrichepp wrote: post #64

Earlier quoted context omitted.

MERCURY IS TOXIC. DO NOT TELL PEOPLE THAT IT IS NOT TOXIC. Both elemental mercury and "organic" mercury are toxic (I assume you mean "organic mercury compounds", since mercury is never "organic"). The relative toxicity of mercury does depend on the compound. Dimethylmercury is exceptionally poisonous: it will go right through latex gloves, skin, and the blood-brain barrier; minute concentrations will kill you. Metall…

I did not say "is not toxic". I said "not very toxic". The OSHA limit is 0.1 mg/m^3. A CFL has 5mg of mercury - so even if every bit of the CFL mercury stayed in a room 13x13x10 feet (which it won't since most gets absorbed by the wall of the CFL) you would still be legal. And that's for continuous exposure! Not a single event. I can't seem to find good data on the LD50 of elemental mercury, everything is for compoun…

From Wikipedia:

> Chronic exposure by inhalation, even at low concentrations in the range 0.7–42 μg/m3, has been shown in case control studies to cause effects such as tremors, impaired cognitive skills, and sleep disturbance in workers.

CFLs are not the only source of mercury. Some barometers and thermometers have significant quantities of the stuff. So if you tell people, "not very toxic", I am worried that these people will think that it is okay not to clean it up.

From: http://www.ehs.gatech.edu/chemical/mercury_and_compounds.pdf

> All forms of mercury are toxic.

> All forms of mercury penetrate the placental barrier and should be considered terratogenic and reproductive effectors.

It lists an exposure limit of 0.025 mg/m3.

Re: The Biggest Thing Since the Light Bulb

#136

Post by bemmu »

FoeNyx wrote: post #69
bemmu wrote: post #49

These are probably available everywhere, but since moving to Japan I found some motion-detecting LED light bulbs. Now when coming home or walking down the hall at night the light turns on automagically. Saves both time and energy.

You said "at night", so it's not only motion-detecting but also comes with a light sensor to avoid to turn on in bright day light, isn't it ? Do you have an URL or a name to provide ?

Found it, it's this one: http://www.amazon.co.jp/dp/B004XKI9GU

Re: The Biggest Thing Since the Light Bulb

#137

Post by dietrichepp »

aaron695 wrote: post #92
dietrichepp wrote: post #64

Earlier quoted context omitted.

MERCURY IS TOXIC. DO NOT TELL PEOPLE THAT IT IS NOT TOXIC. Both elemental mercury and "organic" mercury are toxic (I assume you mean "organic mercury compounds", since mercury is never "organic"). The relative toxicity of mercury does depend on the compound. Dimethylmercury is exceptionally poisonous: it will go right through latex gloves, skin, and the blood-brain barrier; minute concentrations will kill you. Metall…

> MERCURY IS TOXIC. DO NOT TELL PEOPLE THAT IT IS NOT TOXIC. I don't see why this has capitals? The point was valid it's urban legend / vaccinations cause autism style rubbish about breaking light bulbs being bad. When do we get exposed to mercury in real life that we need to highlight mercury is bad in capitals? To stop people breaking light bulbs and licking them? We all know not to drink from a thermometer. I thou…

> We all know not to drink from a thermometer. I though the point of HN is we didn't have to talk at grade school/reddit level.

That's a bad example.

From: http://www.ehs.gatech.edu/chemical/mercury_and_compounds.pdf

> Elemental mercury

> Poses a health hazard because it is volatile and can be absorbed through the skin. As a vapor, penetrates the central nervous system, where it is ionized and trapped, attributing to its extremely toxic effects. Is not well absorbed by the gastrointestinal tract; therefore, when ingested, it is only mildly toxic. Mercury metal and mercury compounds are highly hazardous if inhaled or if they remain on the skin for more than a short period of time.

Saying that CFLs are safe is different from saying that mercury isn't very toxic. There are plenty of compounds which are toxic and found in minute quantities in everyday objects. I'd rather educate people of the dangers.

Re: The Biggest Thing Since the Light Bulb

#139

Post by nitrogen »

zokier wrote: post #125
nitrogen wrote: post #115

Earlier quoted context omitted.

X10 is way too slow and really needs to go away. Instead, bulbs should include a more modern standard, which Hue does (at 6x the price).

That is bit besides the point. Personally I think PLC based system would make most sense for home automation, considering that a large portion of the devices are mains-powered anyways. And if you design the system really cleverly then having the same network extend wirelessly to those nodes where PLC is unsuitable.

Powerline control is fine, but X10 is simply too slow to handle the demands of a modern house with advanced automation. My own system uses DMX-512 and Philips Hue lights (which use Zigbee Light Link). Some of my customers use X10, but the performance is not nearly as good since it can only transmit 20 bits per second.

Re: The Biggest Thing Since the Light Bulb

#140

Post by nitrogen »

rachelbythebay wrote: post #111
jwr wrote: post #77

We are still in the dark ages, though. Just consider: this "bulb" has to plug into the standard 110/230V AC electrical sockets. Powering an LED is nothing like powering an incandescent bulb: you need a constant current driver delivering a precisely measured DC current that, depending on the LED, is between 300mA and (say) 1.5A. The voltage you need depends on the number of LEDs in series, but assume 3.2V per LED. If…

How about power over Ethernet? I'm only half-joking here. If Wikipedia is to be believed, you can get 14 watts from some implementations, 25 from others, and supposedly up to 51 from still others. That seems like more than enough for these new bulbs. I think the last CFL I bought from Ikea was in the neighborhood of 15 watts. The control interface would hopefully evolve naturally from this. :-) (Also, bonus points fo…

Unfortunately PoE as currently implemented is probably not the solution, as there's a non-negligible amount of power lost along the thin wires in a Cat5e cable and in the power converters at each end.
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