Frequently Asked Questions About Converting Fluorescent Fixtures to LED

Q1: Is there a benefit to choosing retrofit LED tubes over ballast compatible?

I like the idea of being able to just switch out the tubes without having to do any wiring, but there must be a reason there are so many retrofit tubes on the market.

Most people switch from fluorescent to LED to save energy. When you do a retrofit installation, aka a “ballast bypass” installation, you essentially get rid of the ballast in the fluorescent fixture. (Whereas with ballast-compatible tubes, you keep the ballast.)

The thing about ballasts, though, is that they use energy—about 25% additional energy than a ballast-free fixture – and that energy usage takes away from the power going to the tube. So, with ballast-compatible tubes, you don't get the full brightness. (We tested this in house, with a 2200 lumen ballast compatible tube and a 2200 retrofit tube, and the difference was noticeable.) Some ballasts also produce a massive voltage surge when you flip the light switch, in order to get the fluorescent tube started. This surge can damage, or even kill, an LED tube.

Additionally, all ballasts will fail over time, and when they do, you'll have to climb back up into your fixtures, remove all your ballast-compatible LED tubes, cut the power to the dead ballasts, install a new ballast, and put all your tubes back up. So, ballast-compatible tubes meet that short-term goal—but they do it at the expense of long-term energy costs and brightness, and you'll still need to replace your ballasts as they start to fail.

These are the reasons why we only offer ballast bypass 8ft LED tubes and almost exclusively offer ballast bypass as an option for 4ft LED tubes as well.

Q2: I have a T12 fixture. Do I have to buy T12 LED tubes?

Our 8ft LED ballast bypass bulbs are compatible with both T12 and T8 fluorescent fixtures. (Since T12 fluorescent tubes are even less efficient than the T8 fluorescents, you’ll see even more significant savings when switching to 8ft LED bulbs that act as a T12 high output LED light.)

Even more good news for you: if you have a fluorescent fixture designed for T12 tubes, you don't need to change out the tombstone when you convert to LED. (If you have T8 tubes, see If I'm doing a retrofit, do I need to buy anything besides the LED tubes? for more information on that.)

Q3: My 8-foot fluorescent fixtures are more than 20 years old. Can I use LED tubes with them? 

If they're still in good condition and you're not itching to install sleek, new integrated LED linear fixtures—absolutely.

The simplest option is to retrofit the fixture so that you can use any 8ft LED tube light with it—and 8ft LED tubes are actually the easiest to retrofit. Simply disconnect the wires running into and out of the ballast and connect them together, hot to hot and neutral to neutral.

Alternately, you may be able to put in a "plug in play" / ballast-compatible 8ft tube, which saves you the trouble of wiring. The downside is that you have to make sure to get one that works with the ballast in your fixture. If you don't know what kind of ballast the fixture has, that can be difficult. Also, ballast compatible tubes, as mentioned in "Is there a benefit to choosing retrofit LED tubes over ballast compatible?", lose efficiency due to the power consumption of the ballast—and you're eventually going to have to replace the ballasts as they fail. ELEDLIghts.com recommends retrofit, ballast-bypass 8ft LED tubes instead for those very reasons.

Q4: Do installation instructions come with your LED tubes?

You bet. You'll find a link to installation instructions (PDF format) with clear wiring diagrams in the support documents section on each tube product page. If you have any questions, our on-staff team of experts are also ready to take your call or answer your text.

Q5: If I'm doing a retrofit, do I need to buy anything besides the LED tubes, or are there other parts I'm going to need to upgrade my fluorescent fixture?

8ft LED tube lights require nothing but the tubes unless the tombstones in your fixture are cracked or broken. If that’s the case, you can purchase new ones pretty inexpensively when you place your tubes order. (Note: If you're replacing T12 tubes, you won't need to change any tombstones; they'll work just fine for the retrofit.)

If you're replacing 4ft fluorescent tubes, you'll need to do a little more hands-on research to find out whether the tombstones in your fixture are "shunted" or "non-shunted." This is because 4ft LED tube lights require one-side power. Which means that when you bypass the ballast, you'll do all the wiring into one—not two—tombstones. For that, you need non-shunted tombstones. Here are two ways you check which your fixture has:

1. Visual examination: If the tombstone has two differently colored wires coming out of it (one black, one white, for instance), it's very likely non-shunted. A non-shunted tombstone has 2 inlets for wires: the hot wire goes in one inlet and the neutral goes in another. With shunted tombstones, there is only one inlet and one wire.
2. Voltage meter: Turn the meter to Ohms, then insert both prongs into the tombstone, as if they were a tube. If the meter lights up or beeps, the tombstone is likely shunted. If it does not, it is likely non-shunted.If you have shunted tombstones on your 4 foot fixtures, you'll need to order one new tombstone for each of your new LED tubes. You'll find them in the accessories section on any 4 foot LED tube product page on our site.

If you have shunted tombstones on your 4 foot fixtures, you'll need to order one new tombstone for each of your new LED tubes. You'll find them in the accessories section on any 4ft LED tube light product page on our site.

Q6: What if I have other questions or run into problems converting my fluorescent fixtures to LED?

We have years of experience with all kinds of fluorescent tube fixtures—simply call or email us for help: 215.355.7200 or lights@eledlights.com!