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SunnySkyguy

DIY LED Luminaires

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With power LED's mounted boards with adequate copper surface or aluminum surface area (~1 sq.in/Watt) cool emission of light can be adapted to almost any fixture with mindful avoidance of glare.

I put these together one day for Winter Seasonal exterior lighting using surplus boards cut down to a 4S string and soldered with AWG 30 and soldered to a stringer of six (6) lamps using AWG 18 speaker wire with a length of 7 meters.

I had a surplus 12V SMPS 2.5A brick and it was plugged into a small extension cord hardwired into an outside garage light fixture (disabled bulb) and mounted using plastic wire staple clips with drywall screws _|````|_ to aluminum soffit under the roof edge.

No current limiting resistors were required since the Voltage was 12.0V and this equated to approx 200~300mA per luminaire and since I knew these LEDs were high quality low ESR the voltage is well matched getting 3.0V per LED. I didn't worry about the exact current as they ran cool and I wasn't looking for a big spot light or torch level brightness.

The brick I had was regulated, but if it was unregulated (~13V with this ~50% load), it would have been too bright and then I might have added a suitable power diode in series to drop the brightness with 1V.

The paper Chinese lanterns were purchased at the Dollar Store ($1) and painted with clear exterior Urethane.. The LEDs were free surplus ( my luck) and adhered to clear strips of scrap polycarbonate plastic bent into a bracket for fastening into the bottom ring with short self-tapping screws. A spring metal wire stretches the lantern from top to bottom.
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  1. SunnySkyguy's Avatar
    Details



    The other parts on board were not used Cap, Vreg and series SMT resistors. They were scrap from a board shop intended as part of a larger array of Ambulance lights or similar and just cut with a hack saw to size.



    I don't remember what the power supply was once used for... maybe an old Router. I have a box full of old bricks. Some I use are 18V so I use 6 LEDs in series and use as many strings in parallel as I need without any matching Rs required. Not all LED's can get away without a small Rs to normalize the strings's ESR.

    hmm I guess I should have resized these images.
  2. SunnySkyguy's Avatar
    Since the board uses epoxy soldermask, it had to be scraped with a blade to expose copper for wire attachment. the same with the magnet wire. (It is also possible to burn thru the coating on 30AWG magnet wire if wrapped around a post, so save time.) with sufficient heat.

    Here more creative examples of DIY home lighting.

    SMT strings under hand rails running from telephone wire hidden to a 12V PC PSU in basement.
    Blue upstairs and Red downstairs. 5m reels come with self-adhesive tape mounted and may be run from 8~14.4V for varying brightness.


    Here is an example of using strings of various surplus LEDs that require 19V ( 6S6P 6 white in series with 6 strings in parallel and 9S2P of Amber) I used a 19.5 universal laptop charger and removed the plug adapter to discover 4 pins. One was used for remote voltage sensing, so I made an interface box wall mounted for dimming the 65W charger, thereby converting a fixed V SMPS into a dimmable LED power supply from 0 to 150%. When on full brightness it was much brighter than direct sunlight and MCPCB"s were hot but touchable.


    I was trying to make the dimmer transition from bright sunlight to dusk with Amber LEDs as shown below for a sunset effect. Chrome egg-crating in ceiling had reduced the glare after I sprayed it black.


    The next example was our garden fence lighting left on a timer and run from an exterior 200W transformer ( Schlumberger) used for power incandescent 8W bulbs that only lasted a few months outside at best, which came with the house. I added a 15A bridge and 2,000 uF cap to feed 16Vdc ( which dropped 1~2V at end of string) with 18AWG providing some drop voltage over 30 meters. 16AWG would have been better, if I wanted perfect matching but the wire resistance of 0.1 between luminaires might have to be added to each feed instead of daisy chain wire resistance. These have been running for years.

    A 24hr timer was used to power the unit with scheduled time. More were used under front deck stairs edges and other exterior places. The Luminaires were made of fence board, sanded and painted with speaker wire running down the fence .
  3. SunnySkyguy's Avatar
    The last was a bad photo of my rooftop UHF antenna with SMT reels wrapped around the post. But I liked it.



    Amber Wall Wash


    Just a sample of my creative LED lighting solutions using just about anything in surplus . Of course one can buy the LED boards in 1W,3W,10W,30W,100W,300W (single/arrays)

    Tony Stewart
    EE since 1975 ( retired)