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Fluorescent to LED 1

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kthree

Mechanical
Aug 9, 2004
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In our office, as well as a few other places within our facility, we have 'cans' recessed into the drop ceiling with regular ballasted 4', T12, fluorescent tubes. As the ballasts go out, we remove the ballast and put in 120v LED tubes. What we are running into is most of this facility was built in 1980 and often the socket for the 2 prong bulb falls apart. Sometimes they are replaceable and other times they are no longer available. So that means sometimes we are able to switch to LED tubes and other times the 'can' sits empty. Of course the 'can' can be replaced but that is a major undertaking and that is why they are sitting empty. What we would like to find is a 2-bulb LED fixture that can simply be installed into the empty 'can' in the place of the 2 fluorescent tubes. We have checked with a couple local electrical supply houses and so far they have found nothing. Considering how many ballasted 'cans' must be in the US, I would think there would be an unbelievably huge market for a quick, easy, inexpensive conversion unit. Any suggestions, ideas, comments any wish to offer will be greatly appreciated. Thanks, K.
 
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These fixtures sound what are called "troffers" in the industry. I'd check with the fixture manufacturer to see if they have conversion kits. A Google search for troffer LED conversions should turn up some options.

Cheers,

Dave
 
I think you're stuck w/ two choices really (if you don't want to do whole-sale changes):

1) Change out the tombstones. I thought most of them are universal, but don't quote me on that. Then, purchase LED tubes and install. Only drawback is the ballasts (still need changing, etc.)

2) You could try to purchase a retro-kit for LED troffers, which would include the drivers and the LED light source. This would allow you to keep the light enclosure.

I don't know the failure rate of LED drivers, so hard to say how they stack up w/ ballasts.

Mike
 
PCB Ballasts?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Thanks All! for considering and responding to my post. Really high quality answers here, and dpc, Thanks again. It makes a world of difference when you know the correct terminology. Appreciate the help. K.
 
You can buy tombstones and screw them in. Otherwise there are lighting repair stores that should be able to provide drop-in replacement ones.

mparenteau; They don't want to screw with ballasts so they're using the LED tubes that are directly driven with 120Vac.

Keith Cress
kcress -
 
The quality of LED lights is all over the place. Many are half wave (tons of flicker), poor spectrum, poor color index, and drivers and LEDs that are very over driven and don't last long.
The less hard you drive LEDs the more efficient they are and the longer that they last.
Im many cases the more expensive ones are well worth it. (look up the Dubai bulb)

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P.E. Metallurgy, consulting work welcomed
 
Depending on the dimension, Phoenix sells complete back panel assemblies for converting their fixtures. They use LED strips attached directly to the back plate. The quality is good but the price is very high. If you have room you could install the back panel into a fixture using a few sheet metal screws and stand-offs.
 
LED lighting is the latest technological lighting advancement on the market right now. LEDs offer a variety of outstanding benefits because they operate differently than traditional fluorescent and incandescent bulbs. Compared to the traditional forms of lighting, LEDs are not only more durable, but they also have a prolonged lifespan and use only a fraction of the amount of energy that other light bulbs on the market use.
 
LED's typically will last 10 seconds, or 10 years. I seem to get the ones with the shorter life.
I have also had a few that last a long time, but the electronics seem to last a short time, so I am stuck with a long life dim bulb.

So go for the quality units.
 
Thanks... didn't know...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
I have purchased a couple of 4' LED fixtures to replace fluorescent fixtures.
They have LED strips directly mounted.
They were replacements for kitchen fixtures.
Lots of light and good colour.
I am happy with them.
I would go all the way to new fixtures or strips if you can find them.
There is something about the idea of using LED tubes with existing tombstones and ballasts DOES NOT make me feel warm and fuzzy.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
It lets you keep all the hardware and the replacements work correctly in the luminare because the light source is in the same location it was designed to be. 7/8 of the battle is mounting the dang fixtures to the ceiling. Using the existing tombstones and just re-wire nutting them into delivering the 120Vac to two tube pins avoids the old ceiling holes and the always inevitable PITA problems that arise because the replacement fixture doesn't exactly cover the old one's footprint. Now a painting problem. (blech!)

Keith Cress
kcress -
 
Retrofit kits exist, maybe even better than you had asked for. I have used one that has all of the parts mounted to magnetic strips, so you just gut the entire troffer and put these in. I love mine, it was a breeze to install and has been working flawlessly for a year of so in my garage, where it gets beastly hot in the summer. They give you screws to permanently mount the strips, I didn't use them (but I did for the driver).




" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
Nice Jeff.
I notice that only two LED strips were used to replace four tubes.
Did you do 2 for 2 or 2 for 4?
How does the light output compare with the tubes? (When they were in good order?)

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
 
The amount of useful light you can get out of LEDs is in the ludicrous speed realm; just bought an 8000-lumen LED "bulb" that screws into a standard socket, which lights up the ENTIRE garage. Hurts the eyes to look directly at this light

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
We retrofitted some Fluorescent fixtures. We hacked the poser supplies to cut the wattage in half on the LEDs and used 4 in a fixture. Cutting the power in half only cuts the light output 35-40% and extends the life by about 10x.
We only wanted to do this once. We also added better smoothing to reduce flicker.
LEDs die usually because cheap capacitors in the power supplies die, or they overheat the LEDs themselves and they die. It is always heat related.
IRS, 8000 lumen mounted base up, don't leave it on for too long or you will be learning how to rebuild the power supply.

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P.E. Metallurgy, consulting work welcomed
 
So I'll admit to bypassing and/or removing the ballasts in some of my garage lights in order to install LED tubes that require a direct connection to 120 V. Since the fixtures were listed at a time when LEDs were not widely available, I believe I may be violating the listing. Jraef too. Comments?
 
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