loading

Many years ago, I installed a string of eight colored lights outside my house. This was before CFL and LED bulbs were available. Although these lights worked perfectly, there was one drawback. As these bulbs were exposed to the weather, a single drop of rain would shatter the bulb when it was switched on. And as years went by, saving electricity became the right thing to do. The eight incandescent bulbs (40W each) consumed 320W of electricity per hour.

Then, CFL bulbs became available.Instead of a 40W bulb, the CFL bulbs are only 7W. Installing the CFL bulbs will save 264W per hour in my setup. However, the cost of a single CFL bulb was the same as 16 incandescent bulbs. There will thus be no return on investment over the lifespan of the CFL bulbs. But again, after the first drop of rain, the CFL bulbs also exploded (although they operate at a much lower temperature). As the CFL bulbs also contains dangerous chemicals, now laying on the grass, they were all removed.

The solution was simple. I needed bulbs that use less energy, are safe to use outdoors in rain, and simple to install.

Step 1: LED Light Strips

I played with some 3528 and 5050 light strips, and after comparing their light output, and cost per meter, I ended up buying the 3528 light strips. There are two options available, waterproof, and non-waterproof. Although the waterproof version would have been the best option, I was unable to get four different colors. I thus ended up buying the non-waterproof strips.

Step 2: LED Light Housing

Getting a housing to install the LED strips in, was a challenge. But after installing some network cables in my house, I got the idea to use the cable trunking I had left over. I hope the pictures will be clear enough for you to follow the steps.

I placed two strips next to each other inside the trunking, and left enough space in the trunking for a terminal block.

After assembly, I used clear silicone to seal the LED strips and solder points.

Finally, I used a small piece of cover to hide the terminal block.

The units were left for the silicone to dry for about 24 hours.

Step 3: Testing the Lights

With the LED strips installed in the trunking, I was afraid that the light will be blocked by the walls of the trunking. However, testing them against a white wall reveled that the LED lights still have about a 90 degrees spread.

Step 4: Power Consuption

Using a small Android App 'LedStips.apk' I created, I calculated the power consumption to be 7.7W. Before installing the new lights, I took some power measurements of the old versus the new lights.

Old incandescent lights - 307Wh

New LED lights - 8.7Wh

This is a saving of 97%.

Step 5: Installation

Each LED light was installed just under the roof tiles. Power for the LED lights was obtained by a cheap 12V, 1A switch mode power supply.

<p>Did you know you can now buy bulbs with LEDs in them that look just like regular bulbs but are 12V. They look almost identical and you could put a colored gel inside them. Go to Banggood.com</p><p><a href="http://www.banggood.com/E27-2_5W-5730-Pure-White-LED-Bulbs-Solar-Lamp-Home-Camping-Light-12V-p-989509.html">http://www.banggood.com/E27-2_5W-5730-Pure-White-L...</a></p>
<p>Thanks for your reply. Yes, I know they are available, but costs almost the same as a CFL bulb when buying locally. 8 Bulbs @ ZAR80.00 = ZAR640.00. <br>I was able to build these lights for around ZAR200.00.</p>

About This Instructable

2,451views

35favorites

License:

More by Eric Brouwer:12V, 2A Uninterruptible Power Supply Easy Project - Bench Power Supply (0 .. 30V, 2 Amp) Design of an Unregulated Power Supply 
Add instructable to: