A much-discussed LED technology has finally come to fruition. There are now Combo Drive LED T8 lamps in the marketplace that work on both line voltage and with fluorescent ballasts. In the past few years, many lesser-known and new to the market manufacturers with minimal lighting knowledge attempted to design lamps in hopes of being the first with this functionality but were unsuccessful. In the case of some, their inventions went up in smoke (literally). After arduous testing, the technology is now viable for LED T8 lamps as well as LED Plug-in lamps.

In the past few years as LED T8’s grew in popularity, customers clamored for an LED T8 that was ballast compatible as well as able to wire up direct to line voltage. Essentially a combination of Type A (ballast compatible) and Type B (ballast bypass) LED tubes. This would allow for a quick install initially by just taking out the fluorescent bulb and installing the LED T8 without touching the ballast. Then when the ballast dies, the LED T8 could wire direct to 120-277V line voltage after the ballast was bypassed.

There are certainly new considerations when dealing with Combo Drive technology, first and foremost being UL listing. Any Type B LED tube that bypasses the ballast comes with a UL listing label that goes on the fixture noting that the fixture has been modified and that the tube is running direct off line voltage. As such, with the Type A + B Combo Drive LED T8 working off the ballast initially, the installer must make note that a UL sticker will be needed when the ballast dies and the T8 tube is wired direct to line voltage. This can be an issue if the ballast dies several years afterwards, at which point it’s possible that someone else is replacing the lighting in the fixture and may not be aware of this.

Up until this point, most who were installing LED T8 lamps were doing so with Type B LED T8’s that bypass the ballast and wire direct. Because of the energy saved when bypassing the ballast as well as the opportunity to remove the ballast as a potential failure point, we still anticipate this being the most popular method going forward. But the new Combo Drive technology is likely to take a big cut into the Type A ballast-compatible market. Type A LED T8’s will always require use of a ballast, and having to buy and install a new ballast when it dies will always be an annoyance. The Combo Drive method that allows for the ballast to be used up and then bypassed is a far more efficient way to utilize the remaining usefulness of the ballast while at the same time being able to move on from this set-up to the more efficient direct line voltage when the ballast is gone. Another benefit is that Combo Drive LED T8’s are compatible on both Instant Start and Program Start ballasts, whereas most Type A lamps are only compatible with Instant Start ballasts.

Not satisfied with providing Combo Drive technology for just LED T8’s, there are also Combo Drive LED PL Lamps. As with LED T8 lamps, there are ballast compatible and ballast bypass LED PL lamps. But bypassing the fluorescent ballast is a bit more difficult with LED PL lamps. In turn, the demand for Combo Drive LED PL lamps was potentially greater than even LED T8 lamps.

The Combo Drive LED PL lamps are available in the following configurations: Horizontally Mounted LED PL, Vertically Mounted LED PL and Extended Vertical Mount LED PL. Note however that horizontal-mount LED PL lamps can work in vertical applications as well.