Commonly designed “UL Type A” – these LED tube lights are designed to be compatible with fluorescent ballasts. They are the most straightforward to implement, since it does not require rewiring the fluorescent fixture.
The UL Type A LED tube light essentially behaves the same a fluorescent lamp, and is a straightforward swap-in.
So, they will not function without ballasts or with magnetic ballasts.
LED tube lights that have a “UL Type B” specification are not compatible with fluorescent ballasts. They cannot be used with the fluorescent ballast, and must be connected directly to mains electricity. The LED driver, however, is integrated into the LED tube itself.
UL Type B LED tubes can further be categorized as single-ended or double ended.
Interacting with the line voltage (which in commercial applications can be up to 277V) does cause potential safety hazards. Therefore, standards have been introduced by safety organizations like UL to ensure that the product can be safely installed. This results in a majority of single-end (SEP) powered instead of double end (DEP) powered tubes
UL Type C LED tubes are relatively uncommon, but offer the most flexibility and efficiency for a lighting system. Unlike a UL Type B LED tube, these do not have the LED driver integrated into the LED tube, and therefore requires a separate LED driver device to be connected between the LED tube and mains electricity.
Type C has a higher upfront cost but is the best future-proofing solution as it offers the ability to work with controls that are currently in place or are installed at a later time