SSC-P4 for indoor lighting

[Sly]

Hi,

I have 6 SSC-P4 I'm not using right now, was thinking about using them for indoor lighting.
I was thinking of indirect ceiling lighting, using a 110-220V converter like these .

Was do you think? Should I use 350mA or 700mA? Of course, I would add some heatsinks, as no air flow would cool this thing.

[Stromberg]

Good idea. I did torchiere/SSC mod couple of months ago and I've been pleased to both output and tint. I used this dimmable driver from dotlight:

http://www.dotlight.de/shop/product_...-1-050-mA.html

..and I can really recommend it over those few euros cheaper models that aren't as flexible to use. You can read about my project from here:

http://www.candlepowerforums.com/vb/...d.php?t=189944

[Sly]

Good, thanks for your reply.
How many leds can I put on a single driver like this?
Do I have to wire them in parallel or series, do I need to add resistor of some sort, or direct drive the led from the driver?

In your DIY project (link above), how do you power the fan? I was thinking of using 120mm fan from computer at 5V, very silent, enough air flow.

[Stromberg]

Lets assume that you would use that 1050mA driver:

• 1-8 leds @350mA(1 watt)
• 1-6 leds @700mA(3 watt)
• 1-X leds @1050mA, X meaning that you have make sure that threshold voltage of led(s) don't exceed 20V

With that same driver, all leds must be wired in series. And you also don't need any additional resistors, since the driver adjusts its output voltage according to selected current(350, 700 or 1050).

I powered the fan with additional universal DC powersource. The fan is rated to 12VDC but I'm driving it at lower voltage(more silent and still cools enough the heatsink).

Ps. if you are planning to use dimming option, you need additional 100kOhm potentiometer which is connected to "DIM." -port of the driver.

[Illum]

I'd give Brlux a PM if you run into questions...
Personally I use 4 fenix lightbars for my fixed lighting needs

His fixed lighting concepts are pretty impressive
My solar powered indoor led lighting
Part II

[Sly]

Ok, so 6 SSC-P4 in series at either 350mA or 700mA would do. If I understood correctly, just wired them together in series (no resistance between them), and back to the driver.

Additional questions:
- To attach to the heatsink, what do you use? Coud I use this: http://www.dotlight.de/shop/product_...tape-Pads.html
- What is dimming used for? Reduce light intensity? Since this is aimed at ceiling light, it will not be adjusted very often, but could be used to adjust settings once in a while...

[Stromberg]

Originally Posted by Sly

Ok, so 6 SSC-P4 in series at either 350mA or 700mA would do. If I understood correctly, just wired them together in series (no resistance between them), and back to the driver.

Yep!

Additional questions:
- To attach to the heatsink, what do you use? Coud I use this: http://www.dotlight.de/shop/product_...tape-Pads.html

Yes you could but I suggest using good thermal adhesive with better thermal conductivity, e.g. Arctic Silver Adhesive:

http://www.arcticsilver.com/arctic_s...l_adhesive.htm

Not as easy to use(remember to read those instructions!) as pads but AFAIK much better heat conductivity and you can place leds more freely on the heatsink.

- What is dimming used for? Reduce light intensity? Since this is aimed at ceiling light, it will not be adjusted very often, but could be used to adjust settings once in a while...

That's correct. I find dimming option very useful since full brightness is not always wanted, e.g. when watching movies.

[Sly]

Hi

I ordered some of the stuff on dotlight. Not thermal paste, I choose the pads, since much chepaer, and will have nice heatsinks + possible fan.
Will udate when received and done.

thanks a lot for your help

[Stromberg]

You're welcome. Remember to post some pictures. Always interested to see what kind of led lighting other people build.

[SafetyBob]

I don't know what you are mounting them to buy my 6 P4's I ran using Advance transformer's version of what you have.....they are glued using that artic silver epoxy. If you are going to get serious about this or you have problems with those LEDs from heat, get the epoxy. You don't need very much to glue the LED's to anything.

But back to my story, I glued my P4 stars on an old 4 foot florescent fixture that used to be the up light in my den. Now the LED's do the uplighting.

Please listen to Stromberg, since his is over there were you are, you guys have the great benefit of being able to get the great German electronics stuff for LED's.....specifically the dimming transformers. We can get them here in the states, but right now ONLY Advance has one that is designed to be dimmed but it is almost impossible to figure out what is the proper dimmer to use with it. They have made it very, very difficult for us "easy" people.

You can get the good stuff easy, so get it. Dimming is what you want. That way, hook up your LEDs to 700mA and dim them down to the level you want. Perfect!!

Bob E.

[Sly]

Hi,

Here's the actual result. I used 6 SSC-P4 LEDs, I run then at 700mA each, in series.
I did not put a fan, since the heatsinks are enough, it's heating a bit, but I can still touch it, so it's reasonable.
I need to paint the box in white, hadn't had time yet. It's simply hanging from the ceiling.

The result is ok to watch movies, but definitely not bright enough to eat dinner comfortably.
I use the regular 5-spot lamp for this.

[shortstack]

try them without the spot reflector, might give of the light a little better, spread it out more

[Opto-King]

I just taked to the company Optoga and they told me that the new operahouse in Oslo (Norway) are using 3pcs of SSC P4 LEDs/fixure in the resturant. You can see a picture of the solution on; www.optodrive.se (front page).

[Sly]

Originally Posted by shortstack

try them without the spot reflector, might give of the light a little better, spread it out more

If you remove the reflector, the beam is too wide, and you loose a lot of light. I've tried this already.

I like it the way it is, the 2 main problems are that the light color is way too white, would like to get warmer white, second problem being a feeling of lack of light.

but it's perfect to watch movies...

[Ken_McE]

Originally Posted by Sly

the light color is way too white, would like to get warmer white

I had this problem with a cool white domelight. My solution was to add a few small yellow and red LEDs around the main emiter. Physically they formed a ring around it and electronically they were wired in parallel.

[SafetyBob]

If you don't add other colored leds to ease the whiteness, then the next time you build a fixture, get the 3000K Seoul P4's. They look much more like a nice bright incan bulb than some stark P4 based flashlight you might build.

To make the light less offensive, you might also consider some clear plastic that you have rubbed with yellow highlighter or perhaps colored plastic wrap in a metal frame you can place infront of the leds to see how you like it before modding the fixture again.

Nice job though!!! Really nice. I appreciate you giving me more ideas....off to Mouser to order more leds!!

Bob E.