Introduction: Converting Drop Ceiling Fluorescent Light to LED
If you've ever spent time in an office, a studio, or any other room with a standard 2' x 4' paneled drop ceiling, you are probably familiar with certain drawbacks of fluorescent tube fixtures. In my case, I was constantly dealing with flickering tubes and humming ballasts. When I checked the cost of replacing the important "guts" of the fixture (the ballast and the tubes), I was looking at roughly $45US per fixture. If I had to spend money, I wanted something that didn't have ballasts.
This is what I came up with...
Step 1: USE CAUTION WHEN DEALING WITH MAINS ELECTRIC POWER!!
Make sure you turn off the circuit breaker for the lights you will be modifying!! If you aren't sure if the breaker is turned off, use a multi-meter or other voltage testing device on the black and white wires. I will mention this again when we get to that part.
All the lighting fixtures in my office/studio are 120VAC. If you have a 208VAC or 240VAC system, you should NOT attempt this modification. Also, I recommend consulting your local electrical code for any additional safety measures that may be required.
Step 2: Gather Your Parts and Tools
This list will be for one (1) fixture. If you have more than one fixture, you'll need this set of parts for every fixture. I found most of this stuff at Lowes Home Improvement and had little luck finding the sockets anywhere else.
- 4 - Standard Base Screw in LED Light Bulbs
- 4 - Servalite #1410LU Phenolic Light Sockets
- 4 - #4 x 3/4 inch, Oval Head Metal Screws
- 4 - Twist-On Wire Connectors, 22 Gauge
- 1 - 60 inch (approximately) length of 14/2 wire
- 1 - 12 inch length of 1/4 inch O.D. (outside diameter) vinyl tubing
- Screwdriver - Phillips Head
- Screwdriver - Flat Head
- Wire cutter and stripper
- Drill bit - 5/64 inch (not pictured)
- Headlamp (optional)
- Voltage Tester
- Tape Measure
- Small Ruler (optional)
- Safety Goggles
- Gloves and Mask (if a fluorescent tube breaks)
Step 3: Prepare the Sockets
I picked these light sockets because they are assembled with a screw and not a rivet. We don't want the mounting bracket, but we want the nice insulated hole that's used to hold the mounting bracket to the socket. So let's remove the bracket.
I found I got the best grip on the screw with a flat head screw driver. When I used the Phillips head, it wanted to strip the screw head. That would be bad, as it would then have to be drilled out (yuck).
Once the bracket has been removed, you will guide one of the #4 x 3/4 inch screws through the hole. Do this for all 4 of the sockets, and set aside until we are ready to install them.
Step 4: Prepare the Light Fixture
Open the lens/cover.
You will have to figure out how your fixture's lens is released. On mine, there were two little metal latches that slid sideways. If yours don't slide, you may have to pry them away from the fixture with a flat head screwdriver. Either way shouldn't require too much force. Be careful, screwdrivers may not be knives, but they can still cut flesh if they slip off the intended target and get forced into a finger or hand.
Once the levers are released, the lens should fold down exposing the tubes. As you can see, mine were in pretty bad shape.
Remove the fluorescent tubes. (Safety goggles suggested.)
Most tubes twist a quarter turn and can be pulled from the fixture. Use caution when removing the tubes. Many of these have a mercury lining which is poisonous. You are safe as long as they don't break. If they do break, DO NOT use a vacuum to clean them up. Find and follow safe clean-up guidelines online.
Remove the metal ballast cover.
Mine had a little tab holding it in place. I just squeezed the cover a little, and the tab popped out. This cover is not usually attached to the light fixture, so be prepared for it to come completely off.
Step 5: Inspect, Trace and Test the Wiring
You will notice a LOT of wire under the cover. Most of it is thinner gauge wire that is permanently attached to the ballast. You are looking for the thicker wires (probably 12 gauge) that come into the fixture through a hole. In my case, there were two hot wires (black) and two neutral wires (white) that came in from the hole. One set of these comes from the light switch ("feeding" the electric to the fixture) and one set goes out to "feed" the next fixture in line.
If you aren't sure if your power is off, now would be the time to check your lines with a voltage tester. One probe inserted into the black mass of wires and one inserted into the white mass of wire. Make sure the probes are touching the copper. If need be, you can carefully remove the twist-on wire connectors to expose the copper. If the light on the indicator comes on, your circuit is still on. Cap the wires and determine which is the correct circuit breaker switch to cut power to this fixture before continuing with the conversion.
Step 6: Installing the Light Sockets
Locate a good flat position between the tombstones
For this part, I temporarily removed the screw we installed in the light socket (Step 3) and held the socket against the metal housing of the fixture, moving it around until I saw it was sitting flat against the metal. Make sure that the hole for the mounting screw of the socket is in the lowest--or 6 o'clock--position. Using your fingers to hold the drill bit, place it through the mounting hole and twist it against the metal to make a mark.
Remove the light socket and measure the distance from your mark to either the top or bottom of the fixture, whichever is easier. In my case, there was a bend in the metal, and my mark was about a 1/4 inch above it. This will be your vertical measurement.
Now find the center between the fluorescent tombstone connectors, and mark it. This is your horizontal measurement.
Use your drill and drill bit to make a hole at the intersection of the vertical and horizontal measurements.
Install the light socket using the #4 x 3/4" screw and a screwdriver. It will be a little hard at first, as you will be creating a thread for the screw (tapping a hole) as you twist the screw into the metal fixture. Again, you want to make sure that the screwdriver tip and the head of the screw are a good match as it will be difficult to tighten the light socket flat against the fixture with a stripped screw head.
Using your horizontal and vertical measurements, continue marking, drilling and mounting the remaining 3 light sockets.
Step 7: Prepare the New Wires
Roll out, straighten and cut two (2) sections of the 14/2 wire. The feed wires coming into my fixture were offset to one end of the fixture, so I cut one length of wire at about 46 inches and another at about 10 inches.
Remove 6 inches of the outer most sheathing/insulation to expose the black wire and the white wire. Do this to both ends of both wires. Use your wire strippers to strip the ends of the black and white wires to expose 1/2 to 5/8 of an inch of the copper wire. This should be enough exposed copper to twist up in the wire connectors.
Step 8: Wiring All the Light Sockets
I am including a basic diagram of how I wired my sockets. Everything should be safe, as long as you are always connecting white to white and black to black. If you are at all unsure about this step, I recommend having a knowledgeable friend or an electrician do the connecting for you.
I started connections at the end of the fixture that is farthest away from the wires coming through the hole that power the fixture. Use one end of the long section of wire that you cut. All three black wires go into one twist connector, and all three white wires go into another twist connector.
(You may want to give each wire a little tug after you think you have them twist connected together. If any of them pull out at all, the connector is not installed properly. Loose wires are never good with electricity, so make sure all the wires are snug in their connectors.)
Next, I made the connections on the other end of the fixture using the short section of wire we prepared. This is pretty much the same as what we just did for the long wire at the other end. All three black wires go into one twist connector, and all three white wires go into another twist connector. Again, make sure all wires are snug in their connectors.
Step 9: Connecting to the Power
At this point, we are ready to connect to the power that is coming into the fixture. As I mentioned in an earlier step, my pictures show two black and two white wires coming into the fixture. One set is the power (feed) coming in to the fixture, the other set of wires is going out to feed power to another fixture further down the ceiling. We will keep them attached as they are and treat both sets as if they are the supply power.
Remove the two twist connectors that connect the ballast wires to the supply power. Carefully remove the ballast wires from each group.
If you want, you can trim back all the wires connected to the tombstone connectors (red, blue and yellow in my pictures) and remove the excess wire and ballasts from the fixture. I left all of mine in place, although it was pretty difficult to get all the wires to stay behind the ballast cover when I replaced it in a later step.
You should have large twist connectors for the last connection. In my case, the original connectors (red in pictures) were of sufficient size and rating to make the connections for all the wires. You want to make sure your twist connectors are rated for however many wires you are connecting together.
Connect all white wires together with one twist connector and all black wires together with the other twist connector. Make sure there are no loose wires by slightly tugging on each.
Step 10: Test All the Connections
I recommend installing your LED light bulbs at this point. Turn the circuit in your breaker box back on, and verify that all the bulbs are indeed connected and lighting up.
If any bulbs aren't lighting up, start troubleshooting by replacing the bulb with a bulb that you know works. If the new bulb isn't coming on, turn off the circuit at your breaker box, and check all the twist connectors. Most likely, one of the wires in the connector is loose and not making a good connection with the others. Turn the circuit on again, and verify that all lights are lighting up.
Once everything is lighting up, I suggest turning the circuit off again to finish reinstalling the ballast cover.
Step 11: Protecting the Wires and Reinstalling the Ballast Cover
We are going to use the vinyl tubing to protect the wires of our new light bulb sockets. On my ballast cover, there were notches at the ends which were great indicators of where the new socket wires would cross over it.
Measure and cut four short lengths of tubing about 3 inches long, enough to cover the areas where wires will cross.
Using the scissors, cut down the lengths of the tubing so that they will slip over the metal ballast cover.
Reinstall the metal ballast cover by slipping it into the slots on one side of the fixture and then pinching it slightly so that the tabs on the other side will slip into their slots. Make sure all the wires are tucked inside of the cover.
Confirm that all of the new socket wires are being protected by the vinyl tubing.
Step 12: Test the Lights Again, Install the Fixture's Lens
It's time to turn your circuit back on at the breaker box and recheck that everything is working properly.
If everything is working, reinstall the fixture's lens.
Enjoy your non-flickering and quiet light!