LED Lighting – converting fluorescent fixtures to LED

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We’ve been in the process of converting our motorhome to LED lighting for a long time. To save money I bought most of the LED’s direct from China on ebay. This has been a bit of a learning experience. Buying from Camping World and such, you get Chinese made bulbs, but hopefully “better quality” ones, for $10 a bulb. On ebay, there are thousands of vendors, American and foreign, all selling the same stuff at a variety of different prices. Direct from China, you’re talking fifty cents to a dollar per bulb, rather than $5 to $15 for exactly the same Chinese bulb from an American vendor such as Camping World or Home Depot.

What I learned the hard way is that the cheapest ones aren’t very good. The first ones I bought, strictly on price, burned up within months. I went back to ebay, bought some slightly more expensive LED’s, and have been very satisfied. I converted all the “hockey puck” light with plugin LED bulbs, they run cool, make good light, and so far have lasted 4 years.

Today, I’m going to continue to work on converting fluorescent fixtures.

RV’s use a ton of these that run on 12 volts and take T-8 or T-12 bulbs. These are a little more complicated than just changing a plugin bulb. They do make “sorta plugin” conversions, but I went my own way and bought RV LED lighting products10 meter strips. Twice actually. The first time I got really cheap ones that were “waterproof.” And they burned up quick. I don’t know if it was the “cheap” or the combination of the waterproof covering and being in an enclosure that caused the overheating, but the next purchase brought strips of bare LED’s, 10 meters each, self adhesive, with 3050 cool white LED’s. The “Number” in these things refers specifically to the size of the LED in millimeters, and along with the density ( # of LED’s per foot or meter) directly relates to how bright they are. The ones I got are very very bright.

After removing the fixture (4 screws and a plug) the next step is to remove the parts
required for the fluorescent lights. Drill out the 6 rivets from the back with a 1/8” bit, pop out the reflector, and the lamp holders and ballast will fall out. Mine had 2 wires, neg is white, pos is red. There was a switch in the housing that I chose to keep, and I cut both wires as close to the ballast as possible.
Prewiring is next. I’m going to use 6 LED strips, I like bright light. I made up 6, 6 inch lengths of small gauge white stranded wire, stripped, wrapped, and soldered to the white wire entering the fixture, and covered the connection with heat shrink tubing. For the hot side, I’m going to setup 2 light levels. I removed ½” of insulation from the red wire going to the switch and attached 2 lengths of green wire as above.

On the red wire coming off the switch I attached 4 lengths of red wire. The fixture will burn 2 or 6 strips of LED’s, switchable by the switch on the housing, with the fixture remaining controlled by the coach’s wall switch.

Now time to peel and stick the LED’s to the reflector.I put  lengths of electrical tape on the end where the connections will be to help insure against short circuits. I used a 12 volt battery and a couple jumper connections to verify that the roll of LED’s work, and to determine where Neg and Pos is. LED’s are polarized, cross the wires, they won’t light up. (It won’t hurt anything, they just don’t light up.) If you look carefully at the LED strip, there are a pair of copper dots between each pair of LED’s. I’m going to solder to those to minimize waste. If you’re less confident in your soldering, there is a pair of solder pads every couple feet, those are easier to solder to, but will produce mucho waste. It’s best just to peel stick cut and go when sticking the LED’s. That way you don’t set anything down and don’t lose track. If they all go on the same direction the Pos and Neg sides will all be aligned. Now go back to your battery and test the first strip, making darned sure you remember which is Pos and which is Neg.
Now carefully solder tin the copper dots where you will attach your wires
(skip if you’re using the big solder pads.) Cut your wires to length, strip a small amount of insulation, tin each wire, then cut the tinned end short, just enough exposed wire to use.
Lay the reflector into the housing and start soldering the wires. A tiny amount of heat on the tinned wire, touch it to the tinned pad and get your iron off, it will stick. White wires to all 6 Neg pads, and I put the green ones one the center 2 and reds on the remaining 4. Be really careful here. I used a small 20 watt soldering iron, very well tinned, and just a touch of heat. With both the pads and the wire tinned, you won’t need any additional solder.
Now snap the reflector down and you’re done. Go back to your battery and test your work. Make sure you get 2 or 6 LED strips depending on flipping the switch. If any strips don’t light, go back to your bench and swap the wires on that strip. Time to plug it in, screw it on, and pop the cover on.
Before I started I hooked up my ammeter. The fluorescent lights need 1.6 amps each. Equipped with 6 strips of LED’s, they are 4 times brighter and only use 1.36 amps. Best of all, with only 2 LED strips on only .45 amps. While of course all the lights (11 in our coach!) are rarely on all together or on all the time, if they were I’ve dropped from 17.6 amps (140 amp/hrs in 8 hours!) to 4.9 amps (39 amp/hrs) and we’re putting way less heat in the air.

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