Compact Fluorescent Lamps

I love that answer, and the 4 channel is brilliant..

However, as speaking of on 120vac, we certainly can dim compact fluorescents.

Not sure of the detail electronics, but I know we sell a good bit of those.

Actually, how highest selling compact fluorescent, is our line of CCFL, Cold Cathode Fluorescent Lamp.

We will sell in excess of 100,000 of those this year alone. These lamps dim quite nicely, with standard incandescent dimmers.

Donald

Really? Hey, do you know the color temperature of those lamps? Maybe there's an alternative that many aquarists have been asking for, but they must have a color temperature above 6500K, which is more suitable for plants photosintesis. A fluorescent lamp that can be dimmed? It would be nice... Do you know the brand name under which they are sold?

Certainly yes. guy, what Campbell Lighting said is right at this point.

there are indeed sorts of dimmer in the market. if you want I can offer as many as you can carry.

Color temperature of a lamp is another thing. in fact, there are else 3600 etc colortemp for these flourescent lamp. and compact lamp.

if you were an electrician I can teach you how to make such dimmer, not difficult.

This is not my string, though I am an electrican and I would like to know!

Thanks Rorschach, very nice point, and nice explanation of how fluorescent lamps work.

I'd like just to know if there are cold cathode fluorescent lamps available in the color temperature range above 6500K.

Rgds.

bhrescobar, for aquarium use you might want to look at an array of Silicon Carbide (blue) LED's instead of fluorescent bulbs for your fish tanks. you'll get a bluer light, closer to what you'd get with a "grow light" type bulb. Say something like Allied Electronics part number 505-0009. you can see it's output wavelength. these should be infinitely dimmable and put out enough light in the 420nM band to allow plants to grow and your salt water fish to show their true colors. these LED's peak output is in the soft UV range and the plastic enclosure is filled with phosphors to convert the soft UV to visible light, much the same way that the phospors on the inner surface of a fluorescent tube convert the UV to visible light. you could string a bunch of them in series and drive two strings (opposite polarity) from the AC line. each LED will want to see about 3 to 3-1/2 volts and will be destroyed if it sees more than 4. so if the line voltage is 120V nominal, then a string of 40 LED's for each string (one to use the positive half of the ac cycle and one to use the negative half.) for a total of 80 led's should net you about 720 candelas at a surrent draw of 20 mA. put say a 1N4004 diode in series with each string to rectify the AC (technically the LED's will do that themselves, but better safe than sorry and the 1n400x series diodes are cheap insurance.) and put a 150V zener across each string, such as a NTE5100A, to prevent voltage spikes from damaging the string. (160V is the maximum a string of 40 could take, a 150V one will limit the voltage each LED will see to about 3.75 volts, well below the 4V max.). you will probably want to put a 6K 5W resistor in series to limit the current to 20mA. The whole setup should pull around 5W and put out LOTS of light.

bhrescobar, here is a stream of consciousness schematic I threw together for you.

Hi, Rorschach!

Sorry I missed reading this in a timely fashion. Lovely. Thanks, and (don't understand why there weren't a myriad of others) a well-desrved GA covering both halves of your response.

Mark

Gracias Mark!

SUPERB!

I'll try to find those here in my place, and check out the price too.

As you stated, it will be just 5W.

Assuming the LED angle to be 15 degrees, I estimate a total output for this system equivalent to 38703 lm according a conversor I found in the web.

Just to let you know some more details, my aquarium have nominal 200 l, which means that the recommended amount of light should be with 50 lm/l roughly 10 000 lm. I could use half of it... maybe I could also sell such a system here... any investors out there?

Regards.

you could use a single string of 40, and plug it into a dimmer if it is still too bright. all the parts are available from Allied Electronics. the led's are $.81 each in these quantities, or $32.40 for the set. the 1N4004 is something like $.03 each. the zener is $.61, the perfboard is $12.75 for a 4" x 5" bit with plated holes. (you could probably get it cheaper elsewhere.). so it will definitely rival a CFL for cost, but it should last 20+ years too and draw a third of the power.

Yes, I can get those for you

Donald