How to Make a Diy Dubai Led Light

Led's are a great invention that revolutionized the lighting industry. They consume less energy and have higher efficiency then incadescent bulbs and halogen also if properly driven have very long lifespan. The problem is here. Manufacturers soon realized that if they produce high quality led light bulbs they could easily last 10 years or even more, which is great for consumers but bad for manufacturers, since their sales would drop due to the long lifespan of led bulbs. So they intentially overdrive leds. That means that they are driving them at higher power that they were designed for which causes problems like overheating. Led's are very sensitive to temperature, higher the temperature quicker they will fail. At 25°C they could last even more then 100.000 hours meanwhile at 70°C they could only last 10.000 hours or usually even less. Most cheap led light bulbs nowadays are overdriven and reach operating temperatures over 80°C, some even over 100°C!!! That degrades the materials in the leds and the driving circuitry and that's why they fail after 1-2 years, some even sooner. In this tutorial i'm gonna show and explain to you how you can extend the lifespan of these led bulbs, by reducing power and subsequently lowering the operating temperature. Ii will be modifying a 24W led light bulb that also has an overheating problem.

This project involves mains voltage so this isn't recommended for beginners in electronics, always make sure that the bulb is unplugged from mains voltage before opening and modifying it!!!

For this project you will need:

-A sharp tool, like a box cutter, knife, spudger... for removing the plastic diffuser.

-A screwdriver

-A soldering iron

-Fine pliers or tweezers

Always double check that the bulb isn't connected to mains voltage when you're modifying it!!!

It's also recommended to short the input pins and the output pins when you disconnect the bulb to discharge the input capacitors, since they could give you a shock if the circuit doesn't have discharging resistors.

Firstly you need to remove the plastic diffuser of the led light bulb. In my case i used a spunger and i put it beween the gap in the plastic and the aluminium case, then slowly made a few rotations to cut the silicone. After that i put a screwdriver in the gap and plastic diffuser just popped off. My led bulb wasn't hard to open, but some of them are very hard or almost impossible to open without damaging them.

After you remove the plastic you can see the aluminium pcb with the led's, now my led bulb had the entire circuitry hidden under the aluminium pcb, but some have linear regulators with the current sensing resistors already on led pcb. In that case you don't have to dissasemble it any further. These bulbs usually use 2 resistors in parallel to get a precise value, in my case 2.32 and 2.40 ohm were used which equals to 1.18 ohm, that provide feedback to the controlling chip or regulator so that it knows how much voltage does it have to put out. So to lower the voltage and subsequently power we need to make the chip think the current is too high. We can do that by simply removing one resistor with pliers or better with a soldering iron. This will increase the resistance by roughly 2 times (from 1.18 ohm to 2.4 ohm) which will increase the voltage drop that the chip senses and thus reduce the total power of the bulb to around half of the original. Of course that all matters which resistor values were chosen but in most cases this will hold true. In my case the power dropped from 24W to 12W, which is great since now the led bulb doesn't overheat anymore. At 24W it reached around 75°C, but now at 12W it barely reaches 55°C and that's with ambient temperature of 30°C, which will extend the lifespan of the led bulb significantly.

If there are no resistors or other circuitry on the top aluminium pcb except led's, you have to remove it firstly to acces the power supply circuitry. In my case i had to remove 3 screw and unsolder the contacts. Then i had access to the power supply. Had to desolder the ac input wires, which are short so it is kinda tricky but with a bit of patience it is doable. High end/high power led bulbs usually use a smps(switch mode power supply), bit lower power use buck converters(non isolated) and the cheapest/lowest power use a capacitive dropper. Mine used a buck converter circuitry, with an input smoothing capacitor, full bridge rectifier, two coils, diode, controlling chip, and two current sensing resistors + 1 discharging resistor. As with the 2.nd step you can remove one resistor to reduce power.

In my case 12W was a bit too low for me, so i decided to increase it to 15W. To do that we need to add a resistor with a different resistance then the one before. It's hard to calculate the exact value of the resistor since datasheets for these driving chips often aren't available, so it's mostly solder and try it. But we can estimate the approximate power. In my case with 1.18ohm parallel resistance it used 24W, with 2.32ohm 12W, so for 15W the required resistance is around 1.8ohm. To get that value we need to put a correct value resistor so the parallel resistance will equal that. For help with the calculations i used this website where i just entered the existing resistance of the resistor on the pcb and for teh second, common resistance values and checked which one is the closest to my required resistance. In my case the original 2.32ohm resistor and 10ohm in parallel resulted in 1.88ohm which is just right. So i soldered the resistor on the pads of the previous resistor and the led bulb should reduce power. My light bulb after the modification consumed right about 15W and heated to 55°C at ambient 30°C which is a great improvement and will result in much longer bulb lifetime. In the other picture i also tried to increase it to 18W, for which i used 2 0603 resistors 1ohm and 3.3ohm in series which worked, but the bulb was still a bit too hot do i decided for 15W.

It's not extremely complicated to reduce power of an led light bulb, so i recommend doing to prolong the lifespan of it and to fight against planed obscelesence and e waste problem.

I hope this tutorial helps you with extending the lifespan of led light bulbs and learning some new skills and knowledge.