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I'm retrofitting the T8 fluorescent tube fixtures in my house with direct wire LED tubes. Essentially, the LED tubes come with drivers inside, so I have to remove the fluorescent lamp ballasts from the existing fixture. The LED tubes can be used with both shunted and non-shunted tombstones, as per the specs:

https://www.homedepot.com/p/HALCO-LIGHTING-TECHNOLOGIES-4-ft-14-Watt-T8-Non-Dimmable-LED-Linear-Light-Bulb-Type-B-Bypass-Double-Ended-Daylight-5000K-10-Pack-T8FR14-850-BYP3-DE-LED10PK-89003/308101924#product-overview

I have had no problem retrofitting my 4-tube fixture. However, my 2-tube fixture is confusing me. The way that it should be wired up is according to this diagram:

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I cannot find the ballast for my 2-tube fixture. I removed the cover in the center, and the wiring that was exposed looks like this:

enter image description here

As you might be able to tell from the image above, there are only a few wires in the fixture. Here is one end of the fixture. The blue arrow points to the cord that goes to the wall socket. There is a green wire (which I presume is ground wire), 2 black wires, and a red wire.

enter image description here

So I was trying to find the ballast, and I thought maybe it might be the small white box in the middle, but I have never seen one so small and light. There are no markings on it either, so I could not search up any model numbers online. The white box is connected to one red wire and one black wire.

enter image description here

I tried eliminating the white box and connecting the two sides of the red wire together, and the same for the black, but it doesn't work. Same goes for trying to connect red to black, black to red.

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I'm pretty confused at this point. Normally black and red indicate live wires, but seeing as there are no white or yellow wires, I'm guessing one of them has to be the neutral, but I don't know which one. I don't know what the white box does, and I don't know where the ballast is.

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It's not going to work with these.

I do a lot of fluorescent conversions - mostly from T12 to T8 since I like real fluorescent.

I recognize those particular fixtures, with the molded-in tombstones and lumps on the ends. These are the "Uber-cheap" variety. They were made as chintzy as possible, and that includes not having a normal ballast. What little ballast they have is actually in the "end plates" on both ends, hence the funny lumps.

You could try hacking open the end casings to get inside them. However, when I tried, I found that I had to do so much damage to get into them that the unit didn't re-assemble properly. I just scrap these when I get them.

If you want a fixture that is more convertible, look around on Craigslist - people often give fluorescent fixtures away for free since they don't fit in standard trash cans. (How do I do it? Bust them up. Plastics in trash, fold over metal frame and put in recycle bin, it's metal.)

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  • +1 I also see a naked splice on one of the black wires - uber-cheap indeed. If OP did any guess-and-checking with this the tubes might be fried now also. Many of the direct wire tubes don't survive if they're hit with the high voltage from the ballast.
    – J...
    Dec 23, 2021 at 20:10
  • @Harper thanks for your reply, that's quite unfortunate. Just out of curiosity, do you know what the white box is for?
    – XYkik
    Dec 23, 2021 at 22:26
  • @J... Yes, I was quite disappointed when I opened it up and saw the naked splice. It was wrapped with a little packing tape... lucky that there hasn't been any accidents in all the years it was used. I'll check the tube used for testing, thanks
    – XYkik
    Dec 23, 2021 at 22:29
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    @XYkik never looked that close, but it's something trivial like an RFI reduction toroid. It may have a role in the ballast functionality, but most of the ballast is in the end caps. Dec 23, 2021 at 23:11

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