As a linear lighting fixture manufacturer, we often have heard of some client refer to LED Tubes as Type A, Type B or Type C tubes. So what does that mean? And, if you’re considering upgrading your fluorescent tubes to LED tubes, or are simply thinking of replacing other LED tubes, you’ll first need to understand installation and operation of the three different types of LED tubes options: Type A LED tubes, Type B LED tubes, and Type C LED tubes.
Type “A” LED Tubes (Ballast Compatible – Plug and Play)
LED Tube with Integrated Driver – Compatible and Operated on Existing LFL Ballast
Description: This UL Type A tube, is designed with an internal driver that allows the tube to operate directly from the existing linear fluorescent ballast. Most of these products are designed to work with T12, T8 and T5 ballasts.
Advantages: UL Type A offers the simplest installation process— retrofitting involves a simple swap of the existing LFL with a UL Type A LED tube. Unlike the other options, no electrical or structural modification of the existing LFL fixture is required.
Disadvantages: However, with these benefits come some limitations. The lifetime of a UL Type A solution is dependent not only on the design life of the LED tube, but on the linear fluorescent ballast life, which could result in additional maintenance and costs within the lifetime of the product. Ballast compatibility will vary by manufacturer and must be checked prior to install.
Additionally, a UL Type A tube sacrifices efficiency due to the additional power loss from the existing ballast and is limited in dimming and controllability.
Type “B” LED Tubes (Internal Driver)
All LED bulbs use drivers that power the LEDs. They perform the function of converting AC power from the utility company into DC power. LED Lights run on DC power. Some LED Tube manufacturers incorporate the drivers inside the tubes. These tubes are call Type “B” LED Tubes.
A Type B LED Tube comes in two varieties, Single Ended Power and Double Ended Power. Single Ended Power (SEP) tubes take power at only one end of the tube. It uses an unshunted tombstone to power it. The other end is just a dummy end. On the power end, there are two pins. One pin takes line power, the other pin take neutral.
Double Ended Powered (DEP) means you send power to each end. This is similar to how fluorescent tubes run. In the case of LED Tubes, you send line to one end and neutral to the other end. Typically it does not matter what end is wired to line or neutral, but check with the manufacturer’s instructions to make sure.
Most important in this installation, the ballast is removed or bypassed. AC Power is sent directly to the tube. So although installation is more involved, you have permanently removed the ballast from the fixture.
Type “C” LED Tubes (External Driver)
LED Tube with Remote Driver
Description: A UL Type C tube, offered among GE’s Refit Solutions as the LED Tube with remote driver, operates with a remote driver that powers the LED linear tube, rather than an integrated driver. Like UL Type B, UL Type C involves electrical modification to the existing fixture, but the low-voltage outputs of the driver are connected to the sockets instead of line voltage.
Advantages: Installation for UL Type C tubes involves removing existing tubes and ballasts, and it may involve replacement of existing sockets, if damaged. The fixture input wires must be connected to the LED driver, and the driver’s low-voltage output wires must then be connected to the sockets before installing the new LED linear tubes. Once installed, this driver can power several LED tubes throughout the fixture.
The UL Type C offers excellent system efficacy, best system compatibility and greatest overall performance. It can be integrated with robust dimming and control functionality, helping to offset moderate labor and installation costs with heightened efficiency well into the future.