LED for Kitchen 4' overhead Fluorescent

[Gary Wolfer]

I was told by several others that the overhead 4- fluorescent was actually 12v and could install LEDs simply by disconnecting the Ballast  I found out they were wrong. I disconnected the ballast and checked voltage across the red and black wires coming to the light and had 110V. Is it fed by the inverter? How can I change it over to 12V can I run a 12v wire to the switch instead of the wire running to the switch or is that only half good enough. The closest 12v roof power would be from the fantastic fan in the kitchen but may be hard to get a wire thru the ceiling and then routed to both sides of the switch. Any suggestions welcome. I intend to put some strip lights in to replace the bulbs. I do not have any wiring diagrams (this is on a 98 Patriot Monticello.

[Edward Buker]

Gary,

You may be better off searching for 120V bulb sockets, there are differing sizes, and mount them on right angles within the current fixture. Take the 120V wires and connect them directly to all the bulb bases that would be wired in parallel and just bypass the ballast transformer and remove it. You should be able to find 120V LED bulbs for those sockets if you plan the sockets and bulbs that work within your space constraints. You would have to use your inverter to power them on 12V but they are low current and that should not be an issue. You would not have to rewire anything within the coach except the fixture. There are a variety of ways to look at this change, you could also modify the exterior face of the fixture, make something out of wood and use miniature LED floodlights. You could also add a 120V Led dimmer if the bulbs you plan on are dimmable. Many things are possible if you want to play...

Later Ed

[Bob Stone]

Another option is use 120 volt LED strip light just as you had intended on doing with the 12 volt LED strips. No change in wiring required except to bypass the ballast and can be made dim able with the appropriate 120 volt, LED compatible dimmer. Search 120 volt LED strip lights on Ebay.
You might want to use the larger 5050 LEDs. Additional strips may be required to achieve a light intensity equivalent to florescent tubes.

[Joel Weiss]

The lumens per watt improvement going from fluorescent to LED is a bit more than a factor of two.  I considered converting this fixture to LED and then realized that I would be spending a fair amount of money to get a ~50 watt reduction in power consumption.  I found that I got a lot of additional lumens by putting in new fluorescent tubes; the old ones looked as if they were the originals.  LEDs are wonderful, but IMHO one has to consider a cost-benefit analysis.

[Gary Wolfer]

Joel the ballast is starting to go out. It is slow to light and flickers on start up and the tubes are turning black on the ends. I use this light more than all the others because I sit at the table across from the kitchen sink and I think it will pay off in the long run. Seems like winter is hard on fluoresents.

[Joel Weiss]

One thing worth considering is replacing the light over the table.  We had a fairly plain fixture above the table that housed two small U-shaped fluorescents (T-somethings).  I replaced the entire fixture with a $40 one from Home Depot which my wife likes a lot better.  In it I put two 60W-equivalent screw-in LED's also purchased at Home Depot.  The increase in lumens was dramatic which my DW really liked because she uses the table for sewing.    I replaced the On/Off switch with a dimmer designed to control LEDs and CFLs and now we have a pleasant dining light as well as a bright worklight.  It was after I did this that I decided converting the fluorescent to LEDs was less essential.

BTW, the new dimmers designed to control screw in LEDs are inexpensive and provide better dimming capability than do standard dimmers.  I've not found them in local stores, but they are readily available online.  Here's what I bought (in brown to match the existing switches):

http://www.amazon.com/gp/product/B00B3613ME/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

[Joel Ashley]

I have to second Joel W.'s conversion, Gary, though I haven't needed to do it myself.  If you have older style fluorscents in that big kitchen overhead, then it is time anyway to consider if you can switch the ballast and lamps over to newer, more efficient T8 fluorescent lighting.  I did that last year in my garage and it made a big difference.  

New narrower tubes use notably less electricity and put out more light.  My garage changeover went from F40 forty watt 4 footers to T8 thirty-two watt ones.  My Beaver however uses two 30 watt 36 inch T12 lamps, and I suspect yours may be the same.   I would expect new T8's to use about 24 watts.  See if a big box or other hardware store has correct length T8 tubes (they use the same sockets as T12's) and the proper ballast.  A Home Depot tech diagramed and explained how to correctly wire in a new ballast for the T8's, which was a big help for me.  No other modification was needed.  As an aside, one big advantage in my garage was the new ballast resolved the stubborn and aggravating cold-start issues I'd had on cool days and nights; the new ones light up immediately every time regardless of ambient temperature.

Whether you go this route or not, take your worn-out ballast and tubes to a big box store as they usually can dispose of the old mercuric devices properly - they don't belong in a landfill and most waste collectors won't take them.

I'd also consider doing as well Joel's table light conversion to LED's;  you will enjoy better lighting overall with less power used, you'll have more versatility, and probably will have spent less money and effort.

Joel

[Gary Wolfer]

I would still rather switch it over to 12V Led Strips I am not too swift on electrical wiring so I have a question. This is my latest thought. I of course have two wires coming in that are wire nutted to the wire going to the ballast. I checked the voltage on those two incoming wires one is black and the other is red. I get 120v (ac) and the switch for the light is on the passenger side of the coach next to another switch that controls the vent fan and the overhead 12v leds now that used to be fluorescents. My question now is could I get 12v dc to the overhead light by disconnecting the hot wire on the 4' florescent switch and jumping a wire from one of the 12v switches input to the 4' fluorescent input side of the switch and would I have to change the common wire at the Light and where does it go? I sure wish I had a 12 and 110 wiring schematic for this coach.

[Edward Buker]

Gary,

You could pull the wire that goes to the light from the 120V switch box and completely isolate it from the 120V circuits. Then install a 12V switch and wiring where it is convenient. By code you are not allowed to have 12V wiring and 120V wiring in the same box. There are multiple ways to accomplish that. If it was a single box and you could pull the 120V wiring from the box you could then supply 12V and use the 120V switch if it was not a dimmer.

I still think the removal of the ballast and 120v leds may be the best way to go with a led dimmer option.

Later Ed

[Gary Wolfer]

ED if the black wire from the light that is wire nutted to the ballast on that end is 120V Now and I disconnected it at the switch and isolated it with a wire nut and tape. Then ran a wire from the 12v hot wire that goes to the 12v switch (IE Pigtail) and connected it to the hot imput wire to the 4' light switch input side would it give me 12V to the 4' light and would I still use the black and red wires that used to connect to the ballast? Where did the Red wire go? Or do I just run the black hot wire and a ground wire to the 12V LED's (PS) the switch is not a dimmer just a 120v switch however it might be a good idea to add a led dimmer to replace that switch.

[Edward Buker]

Gary,

Whatever wire colors leave the switch box should appear coming into the light fixture. There should be a hot a neutral and a ground. The hot wire is typically the black wire and will be the one that is currently connected to the 120V switch. The neutral and ground should have just wire nuts at the switch box. You would isolate all of these wires if you are going to convert to 12V.

You would disconnect all wires from the ballast at the fixture. The Leds are polarized which means there is a + that needs 12V for a 12V Led and a minus that needs a DC ground.  You could us the black wire for a 12V ground and choose red or white if you have it for the +. The ballast would no longer be used. The 120V ground wire would be isolated (not connected) with wire nuts at both ends.

There should be some wiring instructions for the new Leds that you add to the fixture. You cannot use a 120V dimmer, you would need a 12V dimmer made for that purpose or just a switch. You could use an AC style switch without a dimmer. Maintaining proper DC +/- wire polarity you would wire in a switch to the 12V + side that feeds the fixture. You should not have any wiring that connects to any 120V wiring in any way in that switch box you used for a 12V switch or dimmer. All wiring in the box is isolated to the 12V grid or the 120V grid, never both wire types in the same box.

Later Ed

[Jim Nichols]

Lowes and Home Depot in the lighting section have many styles of LED 12v using 120v transfomers. Possibilities?

[Edward Buker]

Jim,

It is possible, but if you have 12V already available then I would probably use it given I would not have to run the inverter unless I wanted to in that case. Also there is always the possibility that you will have hum from the 120v/12v transformer.  Gary needs to figure out how he is going to illuminate the fixture with Leds and then one of these possibilities, including your transformer option, will best fit the Leds he used.

Later Ed

[Joel Weiss]

It is possible, but if you have 12V already available then I would probably use it given I would not have to run the inverter unless I wanted to in that case. Also there is always the possibility that you will have hum from the 120v/12v transformer.  Gary needs to figure out how he is going to illuminate the fixture with Leds and then one of these possibilities, including your transformer option, will best fit the Leds he used.

The one thing to be careful of if you're running LEDs directly off of 12V is that you need to buy ones that have drivers capable of handling ~10-14V which is what they will encounter in an RV.  Many of the ones designed to run off of 12V transformers don't have that broad of an operating range.  That's also true of some of the cheap "direct from China" items found on eBay and elsewhere.

[Steve Huber]

Joel,
Either I was lucky or they've improved. I replaced all my halogen ceiling puck lights with 12 LED lights from China via eBay. Cost was about $1 per. Only "problems' were adjusting for polarity because Beaver didn't when wiring the puck light circuits and reducing the diameter of the LED PC brf slightly to get a good fit. Have had them about  6 mo with no problems.
Steve